/* ==========================================================================
   ORI VOCABULARY ENGINE V1 — BLUE + GREEN + WHITE DESIGN SYSTEM
   Modern • Futuristic • Clean • Calm • Premium • Zero Remote Dependencies
   ========================================================================== */

:root {
  --font-sans: -apple-system, BlinkMacSystemFont, "SF Pro Display", "Segoe UI", Roboto, "Helvetica Neue", sans-serif;
  --font-mono: ui-monospace, "SF Mono", Menlo, Consolas, monospace;

  /* ========================================================================
     STRICT PALETTE TOKENS: BLUE + GREEN + WHITE ONLY (VISUAL SYSTEM V1)
     ======================================================================== */

  /* Primary Blue Family (Core Brand, Navigation, Interaction, Priority) */
  --blue-primary: #0284C7;         /* Precision Blue / Cyan-Blue */
  --blue-primary-hover: #0369A1;   /* Deep Blue Hover */
  --blue-hover: #0369A1;
  --blue-deep: #0369A1;            /* Deep Ocean Blue */
  --blue-light: #F0F9FF;           /* Ultra Light Blue Tint */
  --blue-soft: #F0F9FF;
  --blue-subtle: #E0F2FE;          /* Soft Card Blue Fill */
  --blue-border: #BAE6FD;          /* Crisp Hairline Blue Border */
  --blue-glow: rgba(2, 132, 199, 0.2);

  /* Fresh Green Family (Success, Progress, Mastery, Energy) */
  --green-primary: #059669;        /* Fresh Emerald Green */
  --green-primary-hover: #047857;  /* Deep Forest Green Hover */
  --green-hover: #047857;
  --green-light: #F0FDF4;          /* Ultra Light Green Tint */
  --green-soft: #ECFDF5;
  --green-subtle: #DCFCE7;         /* Soft Card Green Fill */
  --green-border: #BBF7D0;         /* Crisp Hairline Green Border */
  --green-glow: rgba(5, 150, 105, 0.2);

  /* Deep Navy & Slate Neutral (Typography, Hierarchy, Contrast) */
  --navy-900: #0B1329;
  --navy-800: #0F172A;
  --navy-dark: #0F172A;            /* Primary Deep Navy Ink */
  --navy-slate: #1E293B;           /* Heavy Heading Slate */
  --navy-muted: #475569;           /* Secondary Body Slate */
  --navy-faint: #64748B;           /* Faint Metadata Slate */
  --navy-border: #CBD5E1;

  /* Surfaces & Backgrounds (Pure White, Light Blue-Gray Canvas) */
  --surface: #FFFFFF;
  --surface-soft: #F8FAFC;
  --bg-page: #F8FAFC;              /* Clean Crisp Off-White Page Canvas */
  --bg-surface: #FFFFFF;           /* Pure White Card Surface */
  --bg-surface-elevated: #FFFFFF;
  --bg-surface-translucent: rgba(255, 255, 255, 0.94);
  --bg-subtle: #F1F5F9;            /* Neutral Subtle Fill */
  --bg-subtle-hover: #E2E8F0;

  --text-primary: #0F172A;
  --text-secondary: #475569;
  --ink-primary: #0F172A;
  --ink-secondary: #334155;
  --ink-muted: #64748B;
  --ink-faint: #94A3B8;

  /* Hairline Borders & Shadows */
  --border: #E2E8F0;
  --border-light: rgba(226, 232, 240, 0.9);
  --border-focus: rgba(2, 132, 199, 0.45);
  --shadow-subtle: 0 1px 3px rgba(15, 23, 42, 0.04), 0 1px 2px rgba(15, 23, 42, 0.02);
  --shadow-card: 0 1px 3px rgba(15, 23, 42, 0.04), 0 1px 2px rgba(15, 23, 42, 0.02);
  --shadow-hover: 0 8px 24px -4px rgba(15, 23, 42, 0.08), 0 2px 8px -2px rgba(15, 23, 42, 0.03);
  --shadow-elevated: 0 12px 32px -4px rgba(15, 23, 42, 0.07), 0 4px 12px -2px rgba(15, 23, 42, 0.03);
  
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-full: 9999px;

  --transition-fast: 160ms cubic-bezier(0.16, 1, 0.3, 1);
  --transition-smooth: 220ms cubic-bezier(0.16, 1, 0.3, 1);
}

/* Base Reset & Typography */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  -webkit-tap-highlight-color: transparent;
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg-page);
  color: var(--ink-primary);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
}

/* Layout Shell */
.vocab-shell {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  width: 100%;
  max-width: 100vw;
  overflow-x: hidden;
}

/* Navigation Top Bar */
.vocab-topbar {
  position: sticky;
  top: 0;
  z-index: 50;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 24px;
  height: 64px;
  background: var(--bg-surface-translucent);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-light);
}

.vocab-brand {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: inherit;
}

.vocab-brand-logo {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  background: linear-gradient(135deg, var(--blue-primary) 0%, var(--green-primary) 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #FFFFFF;
  font-weight: 800;
  font-size: 16px;
  box-shadow: 0 2px 8px var(--blue-glow);
}

.vocab-brand-text h1 {
  font-size: 16px;
  font-weight: 700;
  letter-spacing: -0.3px;
  color: var(--ink-primary);
  display: flex;
  align-items: center;
  gap: 8px;
}

.vocab-badge-beta {
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.6px;
  text-transform: uppercase;
  background: var(--blue-light);
  color: var(--blue-primary);
  padding: 2px 8px;
  border-radius: var(--radius-full);
  border: 1px solid var(--blue-border);
}

.vocab-brand-text p {
  font-size: 12px;
  color: var(--ink-muted);
}

/* Nav Tabs for Desktop/Tablet */
.vocab-nav-tabs {
  display: flex;
  align-items: center;
  gap: 4px;
  background: var(--bg-subtle);
  padding: 4px;
  border-radius: var(--radius-full);
  border: 1px solid var(--border-light);
}

.vocab-nav-btn {
  background: transparent;
  border: none;
  padding: 7px 16px;
  border-radius: var(--radius-full);
  font-family: inherit;
  font-size: 13px;
  font-weight: 600;
  color: var(--ink-muted);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  transition: all var(--transition-fast);
  white-space: nowrap;
}

.vocab-nav-btn:hover {
  color: var(--ink-primary);
}

.vocab-nav-btn.active {
  background: var(--bg-surface);
  color: var(--blue-primary);
  box-shadow: var(--shadow-subtle);
}

.vocab-nav-btn .badge {
  font-size: 11px;
  padding: 1px 6px;
  border-radius: 10px;
  background: var(--bg-subtle);
  color: var(--ink-secondary);
}

.vocab-nav-btn.active .badge {
  background: var(--green-subtle);
  color: var(--green-primary);
}

.vocab-topbar-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

.btn-test-platform {
  text-decoration: none;
  color: var(--ink-secondary);
  font-size: 13px;
  font-weight: 600;
  padding: 8px 14px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-light);
  background: var(--bg-surface);
  transition: all var(--transition-fast);
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.btn-test-platform:hover {
  background: var(--bg-subtle);
  color: var(--blue-primary);
  border-color: var(--blue-border);
}

/* Mobile Bottom Navigation Bar */
.vocab-bottom-bar {
  display: none;
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  height: 60px;
  background: var(--bg-surface-translucent);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-top: 1px solid var(--border-light);
  z-index: 100;
  align-items: center;
  justify-content: space-around;
  padding: 0 8px;
}

.vocab-tab-mobile {
  background: transparent;
  border: none;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 3px;
  color: var(--ink-muted);
  font-size: 11px;
  font-weight: 600;
  padding: 6px 12px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all var(--transition-fast);
  min-height: 48px;
  min-width: 60px;
}

.vocab-tab-mobile.active {
  color: var(--blue-primary);
}

.vocab-tab-mobile svg {
  width: 20px;
  height: 20px;
}

/* Main Workspace */
.vocab-main {
  flex: 1;
  max-width: 1400px;
  width: 100%;
  margin: 0 auto;
  padding: 28px 24px 60px;
  box-sizing: border-box;
}

/* View Sections */
.vocab-view {
  display: none;
  animation: fadeIn 200ms ease;
}

.vocab-view.active {
  display: block;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(4px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ==========================================================================
   VIEW 1: VOCABULARY DASHBOARD (HOME)
   ========================================================================== */
.dashboard-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  margin-bottom: 28px;
  flex-wrap: wrap;
  gap: 16px;
}

.dashboard-title-area h2 {
  font-size: 26px;
  font-weight: 800;
  letter-spacing: -0.5px;
  color: var(--ink-primary);
  margin-bottom: 6px;
}

.dashboard-title-area p {
  font-size: 14px;
  color: var(--ink-secondary);
}

.dashboard-quick-stats {
  display: flex;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
}

.quick-stat-pill {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  padding: 8px 16px;
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-subtle);
  display: flex;
  align-items: center;
  gap: 10px;
}

.quick-stat-icon {
  font-size: 18px;
}

.quick-stat-info .num {
  font-size: 16px;
  font-weight: 700;
  color: var(--ink-primary);
  line-height: 1.2;
}

.quick-stat-info .label {
  font-size: 11px;
  color: var(--ink-muted);
  font-weight: 600;
}

/* Dashboard Hero Card */
.mastery-hero-card {
  background: linear-gradient(135deg, rgba(2, 132, 199, 0.04) 0%, rgba(5, 150, 105, 0.04) 100%), var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 28px;
  margin-bottom: 32px;
  box-shadow: var(--shadow-card);
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 28px;
  flex-wrap: wrap;
}

.mastery-hero-left {
  max-width: 580px;
}

.mastery-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.8px;
  color: var(--blue-primary);
  background: var(--blue-light);
  padding: 4px 10px;
  border-radius: var(--radius-full);
  border: 1px solid var(--blue-border);
  margin-bottom: 12px;
}

.mastery-hero-left h3 {
  font-size: 22px;
  font-weight: 800;
  letter-spacing: -0.4px;
  margin-bottom: 8px;
  color: var(--ink-primary);
}

.mastery-hero-left p {
  font-size: 14px;
  color: var(--ink-secondary);
  line-height: 1.6;
  margin-bottom: 18px;
}

.mastery-hero-actions {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.btn-primary {
  background: var(--blue-primary);
  color: #FFFFFF;
  border: none;
  font-family: inherit;
  font-size: 14px;
  font-weight: 600;
  padding: 10px 20px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  transition: all var(--transition-fast);
  box-shadow: 0 2px 8px var(--blue-glow);
  text-decoration: none;
}

.btn-primary:hover {
  background: var(--blue-primary-hover);
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(2, 132, 199, 0.35);
}

.btn-secondary {
  background: var(--bg-surface);
  color: var(--ink-primary);
  border: 1px solid var(--border-light);
  font-family: inherit;
  font-size: 14px;
  font-weight: 600;
  padding: 10px 18px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  transition: all var(--transition-fast);
  text-decoration: none;
}

.btn-secondary:hover {
  background: var(--bg-subtle);
  border-color: var(--blue-border);
  color: var(--blue-primary);
}

.mastery-hero-right {
  display: flex;
  align-items: center;
  gap: 24px;
}

.progress-circle-wrap {
  position: relative;
  width: 110px;
  height: 110px;
}

.progress-circle-svg {
  width: 100%;
  height: 100%;
  transform: rotate(-90deg);
}

.progress-circle-bg {
  fill: none;
  stroke: var(--bg-subtle);
  stroke-width: 10;
}

.progress-circle-fill {
  fill: none;
  stroke: var(--blue-primary);
  stroke-width: 10;
  stroke-linecap: round;
  transition: stroke-dashoffset 600ms cubic-bezier(0.16, 1, 0.3, 1);
}

.progress-circle-inner {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  text-align: center;
}

.progress-circle-percent {
  font-size: 22px;
  font-weight: 800;
  color: var(--ink-primary);
  line-height: 1;
}

.progress-circle-label {
  font-size: 10px;
  font-weight: 600;
  color: var(--ink-muted);
  text-transform: uppercase;
}

/* Cumulative Levels Grid */
.section-subtitle {
  font-size: 18px;
  font-weight: 700;
  color: var(--ink-primary);
  margin-bottom: 16px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.levels-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(min(100%, 360px), 1fr));
  gap: 20px;
  margin-bottom: 40px;
}

.level-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 22px;
  box-shadow: var(--shadow-subtle);
  transition: all var(--transition-fast);
  cursor: pointer;
  position: relative;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.level-card:hover {
  transform: translateY(-2px);
  border-color: var(--blue-border);
  box-shadow: var(--shadow-card);
}

.level-card.active-level {
  border-color: var(--blue-primary);
  box-shadow: 0 0 0 1px var(--blue-primary), var(--shadow-card);
}

.level-card-top {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 14px;
}

.level-badge {
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.6px;
  padding: 3px 8px;
  border-radius: var(--radius-sm);
  background: var(--blue-light);
  color: var(--blue-primary);
  border: 1px solid var(--blue-border);
}

.level-score-band {
  font-size: 12px;
  font-weight: 600;
  color: var(--green-primary);
}

.level-card-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--ink-primary);
  margin-bottom: 4px;
}

.level-card-desc {
  font-size: 13px;
  color: var(--ink-muted);
  line-height: 1.5;
  margin-bottom: 18px;
}

.level-progress-bar-wrap {
  background: var(--bg-subtle);
  height: 6px;
  border-radius: var(--radius-full);
  overflow: hidden;
  margin-bottom: 10px;
}

.level-progress-bar {
  background: linear-gradient(90deg, var(--blue-primary) 0%, var(--green-primary) 100%);
  height: 100%;
  border-radius: var(--radius-full);
  transition: width 400ms ease;
}

.level-card-foot {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 12px;
  color: var(--ink-muted);
}

/* ==========================================================================
   VIEW 2: LEVEL MAP (CORE 50 PROTOTYPE EXPLORER)
   ========================================================================== */
.explorer-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 20px;
  flex-wrap: wrap;
  gap: 16px;
}

.explorer-controls {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  width: 100%;
  margin-bottom: 20px;
}

.search-box-wrap {
  flex: 1;
  min-width: 240px;
  position: relative;
}

.search-input {
  width: 100%;
  padding: 10px 14px 10px 38px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-light);
  background: var(--bg-surface);
  font-family: inherit;
  font-size: 14px;
  color: var(--ink-primary);
  outline: none;
  transition: border-color var(--transition-fast);
}

.search-input:focus {
  border-color: var(--blue-primary);
  box-shadow: 0 0 0 3px rgba(2, 132, 199, 0.15);
}

.search-icon {
  position: absolute;
  left: 12px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--ink-faint);
  pointer-events: none;
}

.filter-chips {
  display: flex;
  align-items: center;
  gap: 6px;
  overflow-x: auto;
  padding-bottom: 2px;
}

.filter-chip {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  padding: 8px 14px;
  border-radius: var(--radius-sm);
  font-family: inherit;
  font-size: 12px;
  font-weight: 600;
  color: var(--ink-secondary);
  cursor: pointer;
  white-space: nowrap;
  transition: all var(--transition-fast);
}

.filter-chip:hover {
  background: var(--bg-subtle);
  color: var(--ink-primary);
}

.filter-chip.active {
  background: var(--blue-primary);
  color: #FFFFFF;
  border-color: var(--blue-primary);
}

/* Words Table / List */
.word-list-container {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-subtle);
  overflow: hidden;
}

.word-list-header {
  display: grid;
  grid-template-columns: 70px 1.4fr 90px 100px 120px 120px 1fr 60px;
  padding: 12px 18px;
  background: var(--bg-subtle);
  border-bottom: 1px solid var(--border-light);
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.6px;
  color: var(--ink-muted);
  align-items: center;
}

.word-row {
  display: grid;
  grid-template-columns: 70px 1.4fr 90px 100px 120px 120px 1fr 60px;
  padding: 14px 18px;
  border-bottom: 1px solid var(--border-light);
  align-items: center;
  cursor: pointer;
  transition: background var(--transition-fast);
}

.word-row:last-child {
  border-bottom: none;
}

.word-row:hover {
  background: var(--blue-light);
}

.word-rank {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  color: var(--ink-muted);
}

.word-lemma-group {
  display: flex;
  align-items: center;
  gap: 10px;
}

.word-lemma {
  font-size: 15px;
  font-weight: 700;
  color: var(--ink-primary);
}

/* POS tags: Blue / Green / Neutral palette only */
.pos-tag {
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  padding: 2px 7px;
  border-radius: 4px;
}

.pos-noun { background: var(--blue-subtle); color: var(--blue-deep); border: 1px solid var(--blue-border); }
.pos-verb { background: var(--green-subtle); color: var(--green-primary); border: 1px solid var(--green-border); }
.pos-adj  { background: var(--blue-light); color: var(--blue-primary); border: 1px solid var(--blue-border); }
.pos-adv  { background: var(--bg-subtle); color: var(--navy-muted); border: 1px solid var(--border-light); }

.feature-indicators {
  display: flex;
  align-items: center;
  gap: 5px;
}

.indicator-badge {
  font-size: 10px;
  font-weight: 700;
  padding: 2px 5px;
  border-radius: 4px;
  border: 1px solid var(--border-light);
  background: var(--bg-subtle);
  color: var(--ink-muted);
  cursor: default;
}

.indicator-badge.active-m {
  background: var(--green-subtle);
  color: var(--green-primary);
  border-color: rgba(5, 150, 105, 0.3);
}

.indicator-badge.active-f {
  background: var(--blue-subtle);
  color: var(--blue-primary);
  border-color: rgba(2, 132, 199, 0.3);
}

.indicator-badge.active-c {
  background: var(--green-light);
  color: var(--green-primary);
  border-color: rgba(5, 150, 105, 0.25);
}

.indicator-badge.active-p5 {
  background: var(--blue-light);
  color: var(--blue-deep);
  border-color: var(--blue-border);
}

.word-freq-cell {
  font-size: 13px;
  font-weight: 600;
  color: var(--ink-primary);
}

.word-tests-cell {
  font-size: 12px;
  color: var(--ink-muted);
}

.status-dot-cell {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 12px;
  font-weight: 600;
}

.status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  display: inline-block;
}

.dot-not-started { background: var(--ink-faint); }
.dot-learning { background: var(--blue-primary); }
.dot-review { background: var(--green-primary); }
.dot-mastered { background: var(--green-primary); }

.bookmark-btn {
  background: transparent;
  border: none;
  font-size: 16px;
  color: var(--ink-faint);
  cursor: pointer;
  padding: 4px;
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
}

.bookmark-btn:hover {
  color: var(--green-primary);
}

.bookmark-btn.saved {
  color: var(--green-primary);
}

/* ==========================================================================
   VIEW 3: WORD DETAIL SCREEN (5-STEP EXPERIENCE)
   ========================================================================== */
.detail-back-bar {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 20px;
}

.btn-back {
  background: transparent;
  border: 1px solid var(--border-light);
  padding: 6px 14px;
  border-radius: var(--radius-sm);
  font-family: inherit;
  font-size: 13px;
  font-weight: 600;
  color: var(--ink-secondary);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.btn-back:hover {
  background: var(--bg-subtle);
  color: var(--blue-primary);
  border-color: var(--blue-border);
}

/* Word Detail Hero Header */
.word-detail-header-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 28px;
  box-shadow: var(--shadow-card);
  margin-bottom: 24px;
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  flex-wrap: wrap;
  gap: 20px;
}

.word-detail-title-group {
  display: flex;
  align-items: baseline;
  gap: 14px;
  margin-bottom: 10px;
  flex-wrap: wrap;
}

.detail-lemma-title {
  font-size: 36px;
  font-weight: 900;
  letter-spacing: -0.8px;
  color: var(--ink-primary);
  line-height: 1.1;
}

.detail-pos-badge {
  font-size: 14px;
  font-weight: 700;
  text-transform: uppercase;
  padding: 4px 10px;
  border-radius: var(--radius-sm);
}

.detail-rank-badge {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  background: var(--blue-light);
  color: var(--blue-deep);
  border: 1px solid var(--blue-border);
  padding: 4px 10px;
  border-radius: var(--radius-sm);
}

.detail-slot-audio {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 13px;
  color: var(--ink-muted);
  margin-bottom: 14px;
}

.btn-audio-stub {
  background: var(--bg-subtle);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-full);
  padding: 4px 12px;
  font-size: 12px;
  font-weight: 600;
  color: var(--ink-muted);
  cursor: not-allowed;
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.detail-meta-chips {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}

.meta-chip {
  background: var(--bg-subtle);
  border-radius: var(--radius-full);
  padding: 4px 12px;
  font-size: 12px;
  font-weight: 600;
  color: var(--ink-secondary);
}

/* Learning Actions Bar */
.detail-actions-panel {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}

.btn-action-save {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  padding: 10px 16px;
  border-radius: var(--radius-sm);
  font-family: inherit;
  font-size: 13px;
  font-weight: 600;
  color: var(--ink-primary);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  transition: all var(--transition-fast);
}

.btn-action-save.saved {
  background: var(--green-subtle);
  color: var(--green-primary);
  border-color: rgba(5, 150, 105, 0.3);
}

.btn-action-state {
  border: none;
  padding: 10px 18px;
  border-radius: var(--radius-sm);
  font-family: inherit;
  font-size: 13px;
  font-weight: 700;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  transition: all var(--transition-fast);
}

.btn-state-learning {
  background: var(--blue-subtle);
  color: var(--blue-primary);
  border: 1px solid var(--blue-border);
}

.btn-state-mastered {
  background: var(--green-primary);
  color: #FFFFFF;
}

/* 5-Step Learning Sections */
.detail-sections-container {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.detail-section-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 24px;
  box-shadow: var(--shadow-subtle);
}

.section-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 16px;
  border-bottom: 1px solid var(--border-light);
  padding-bottom: 12px;
}

.section-title-wrap {
  display: flex;
  align-items: center;
  gap: 10px;
}

.section-number {
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--blue-primary);
  color: #FFFFFF;
  font-size: 12px;
  font-weight: 800;
  display: flex;
  align-items: center;
  justify-content: center;
}

.section-title {
  font-size: 16px;
  font-weight: 800;
  letter-spacing: -0.2px;
  text-transform: uppercase;
  color: var(--ink-primary);
}

.section-status-tag {
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  padding: 2px 8px;
  border-radius: var(--radius-full);
}

.status-tag-verified { background: var(--green-subtle); color: var(--green-primary); border: 1px solid var(--green-border); }
.status-tag-pending  { background: var(--blue-light); color: var(--blue-primary); border: 1px solid var(--blue-border); }
.status-tag-opaque   { background: var(--bg-subtle); color: var(--ink-muted); border: 1px solid var(--border-light); }

/* Section A: Word DNA (Morphology) */
.dna-connector-box {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 20px;
  background: var(--bg-subtle);
  border-radius: var(--radius-md);
  margin-bottom: 16px;
  overflow-x: auto;
}

.dna-chip {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 14px 20px;
  text-align: center;
  box-shadow: var(--shadow-subtle);
  min-width: 110px;
  transition: transform var(--transition-fast);
}

.dna-chip:hover {
  transform: translateY(-2px);
  border-color: var(--blue-primary);
}

.dna-chip-form {
  font-size: 18px;
  font-weight: 800;
  color: var(--ink-primary);
  margin-bottom: 4px;
}

.dna-chip-type {
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  color: var(--blue-primary);
  letter-spacing: 0.6px;
}

.dna-plus {
  font-size: 20px;
  font-weight: 800;
  color: var(--ink-faint);
}

.dna-explanation {
  font-size: 13px;
  color: var(--ink-secondary);
  line-height: 1.6;
  background: var(--blue-light);
  border-left: 3px solid var(--blue-primary);
  padding: 10px 14px;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}

/* Section B: Word Family */
.family-network {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(min(100%, 200px), 1fr));
  gap: 12px;
}

.family-member-card {
  background: var(--bg-subtle);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 14px;
  transition: all var(--transition-fast);
}

.family-member-card.is-current {
  background: var(--blue-subtle);
  border-color: var(--blue-primary);
}

.member-word {
  font-size: 15px;
  font-weight: 700;
  color: var(--ink-primary);
  margin-bottom: 4px;
}

.member-meta {
  font-size: 12px;
  color: var(--ink-muted);
  display: flex;
  justify-content: space-between;
}

/* Section C: Collocations */
.collocations-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(min(100%, 260px), 1fr));
  gap: 12px;
}

.colloc-item-card {
  background: var(--bg-subtle);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 14px 18px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: all var(--transition-fast);
}

.colloc-item-card:hover {
  background: var(--bg-surface);
  border-color: var(--blue-border);
  box-shadow: var(--shadow-subtle);
}

.colloc-phrase {
  font-size: 14px;
  font-weight: 700;
  color: var(--ink-primary);
}

.colloc-freq {
  font-size: 11px;
  font-weight: 700;
  color: var(--green-primary);
  background: var(--green-subtle);
  padding: 2px 8px;
  border-radius: var(--radius-full);
  border: 1px solid var(--green-border);
}

/* Section D: TOEIC Usage */
.usage-exam-card {
  background: var(--bg-subtle);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 18px;
  margin-bottom: 14px;
}

.usage-exam-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 8px;
}

.usage-prov-tag {
  font-size: 11px;
  font-weight: 700;
  color: var(--ink-muted);
  text-transform: uppercase;
}

.usage-part-badge {
  font-size: 10px;
  font-weight: 800;
  background: var(--blue-subtle);
  color: var(--blue-deep);
  border: 1px solid var(--blue-border);
  padding: 2px 6px;
  border-radius: 4px;
}

.usage-sentence {
  font-size: 14px;
  color: var(--ink-primary);
  line-height: 1.6;
  margin-bottom: 10px;
  font-style: italic;
}

.usage-tip-box {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-sm);
  padding: 10px 14px;
  font-size: 13px;
  color: var(--ink-secondary);
}

/* Distribution Bars */
.usage-freq-bars {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(110px, 1fr));
  gap: 10px;
  margin-top: 14px;
}

.freq-bar-item {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-sm);
  padding: 8px 12px;
  text-align: center;
}

.freq-bar-num {
  font-size: 16px;
  font-weight: 800;
  color: var(--ink-primary);
}

.freq-bar-lbl {
  font-size: 10px;
  font-weight: 700;
  text-transform: uppercase;
  color: var(--ink-muted);
}

/* ==========================================================================
   VIEW 4: SAVED WORDS (STUDENT BASKET)
   ========================================================================== */
.saved-header {
  margin-bottom: 24px;
}

.saved-header h2 {
  font-size: 24px;
  font-weight: 800;
  margin-bottom: 6px;
}

.saved-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(min(100%, 300px), 1fr));
  gap: 16px;
}

.saved-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 18px;
  box-shadow: var(--shadow-subtle);
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: all var(--transition-fast);
  cursor: pointer;
}

.saved-card:hover {
  transform: translateY(-2px);
  border-color: var(--blue-border);
  box-shadow: var(--shadow-card);
}

.saved-card-left h4 {
  font-size: 16px;
  font-weight: 700;
  color: var(--ink-primary);
  margin-bottom: 4px;
}

.saved-card-left p {
  font-size: 12px;
  color: var(--ink-muted);
}

.btn-remove-saved {
  background: transparent;
  border: none;
  color: var(--ink-faint);
  font-size: 18px;
  cursor: pointer;
  padding: 6px;
  border-radius: var(--radius-sm);
  transition: color var(--transition-fast);
}

.btn-remove-saved:hover {
  color: var(--navy-dark);
}

/* Empty State */
.empty-state {
  text-align: center;
  padding: 60px 20px;
  color: var(--ink-muted);
}

.empty-state-icon {
  font-size: 44px;
  margin-bottom: 12px;
  opacity: 0.6;
}

/* ==========================================================================
   VIEW 5: REVIEW MODE (SPACED REPETITION PROTOTYPE)
   ========================================================================== */
.review-container {
  max-width: 680px;
  margin: 0 auto;
}

.review-progress-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 20px;
  font-size: 13px;
  font-weight: 700;
  color: var(--ink-muted);
}

.flashcard-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 36px 28px;
  box-shadow: var(--shadow-elevated);
  text-align: center;
  margin-bottom: 24px;
  min-height: 380px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  transition: all var(--transition-smooth);
}

.flashcard-front-content {
  width: 100%;
}

.flashcard-word {
  font-size: 42px;
  font-weight: 900;
  letter-spacing: -0.8px;
  color: var(--ink-primary);
  margin-bottom: 8px;
}

.flashcard-pos {
  font-size: 14px;
  font-weight: 700;
  text-transform: uppercase;
  color: var(--blue-primary);
  margin-bottom: 20px;
}

.flashcard-structure-clue {
  display: inline-block;
  background: var(--bg-subtle);
  border: 1px dashed var(--blue-border);
  padding: 8px 16px;
  border-radius: var(--radius-sm);
  font-size: 13px;
  color: var(--ink-secondary);
  margin-bottom: 24px;
}

.btn-reveal-solution {
  background: var(--blue-primary);
  color: #FFFFFF;
  border: none;
  font-family: inherit;
  font-size: 15px;
  font-weight: 700;
  padding: 12px 28px;
  border-radius: var(--radius-full);
  cursor: pointer;
  box-shadow: 0 4px 14px var(--blue-glow);
  transition: all var(--transition-fast);
}

.btn-reveal-solution:hover {
  background: var(--blue-primary-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(2, 132, 199, 0.4);
}

/* Revealed Content */
.flashcard-back-content {
  width: 100%;
  text-align: left;
  display: none;
  animation: fadeIn 200ms ease;
}

.flashcard-back-content.visible {
  display: block;
}

.review-action-buttons {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 10px;
  margin-top: 24px;
}

.btn-review-rating {
  border: 1px solid transparent;
  padding: 12px;
  border-radius: var(--radius-sm);
  font-family: inherit;
  font-size: 13px;
  font-weight: 700;
  cursor: pointer;
  transition: all var(--transition-fast);
}

/* Rating buttons: Clean slate / blue / green palette */
.btn-rate-again    { background: var(--bg-subtle); color: var(--navy-muted); border-color: var(--border-light); }
.btn-rate-hard     { background: var(--blue-light); color: var(--blue-primary); border-color: var(--blue-border); }
.btn-rate-good     { background: var(--green-light); color: var(--green-primary); border-color: var(--green-border); }
.btn-rate-mastered { background: var(--green-primary); color: #FFFFFF; }

.btn-review-rating:hover {
  transform: translateY(-2px);
  filter: brightness(0.97);
}

/* Toast Message */
.vocab-toast {
  position: fixed;
  bottom: 80px;
  left: 50%;
  transform: translateX(-50%) translateY(20px);
  background: var(--navy-dark);
  color: #FFFFFF;
  padding: 10px 20px;
  border-radius: var(--radius-full);
  border: 1px solid rgba(2, 132, 199, 0.3);
  font-size: 13px;
  font-weight: 600;
  box-shadow: var(--shadow-elevated);
  opacity: 0;
  pointer-events: none;
  transition: all 200ms ease;
  z-index: 200;
  display: flex;
  align-items: center;
  gap: 8px;
}

.vocab-toast.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

/* ==========================================================================
   RESPONSIVE DESIGN SYSTEM
   Desktop (1440x900) • Tablet (768x1024) • Mobile (390x844)
   ========================================================================== */

@media (max-width: 1024px) {
  .word-list-header, .word-row {
    grid-template-columns: 50px 1.2fr 70px 80px 100px 1fr 50px;
  }
}

.mobile-only-inline { display: none; }
.desktop-only-inline { display: inline; }

@media (max-width: 640px) {
  .mobile-only-inline { display: inline; }
  .desktop-only-inline { display: none; }

  .vocab-topbar {
    padding: 0 12px;
    height: 54px;
  }

  .vocab-brand {
    gap: 8px;
  }

  .vocab-brand-logo {
    width: 28px;
    height: 28px;
    font-size: 13px;
  }

  .vocab-brand-text h1 {
    font-size: 13px;
    letter-spacing: -0.2px;
  }

  .vocab-badge-beta {
    font-size: 9px;
    padding: 1px 5px;
  }

  .vocab-brand-text p {
    display: none;
  }

  .btn-test-platform {
    padding: 6px 10px;
    font-size: 12px;
  }
  
  .vocab-nav-tabs {
    display: none; /* Switch to bottom tab bar on mobile */
  }

  .vocab-bottom-bar {
    display: flex;
  }

  .vocab-main {
    padding: 14px 12px 84px; /* Space for bottom bar */
  }

  .mastery-hero-card {
    padding: 18px 14px;
    flex-direction: column;
    align-items: flex-start;
  }

  .mastery-hero-right {
    width: 100%;
    justify-content: flex-start;
  }

  .word-list-header {
    display: none; /* Card stream on mobile */
  }

  .word-row {
    grid-template-columns: 1fr auto;
    padding: 12px 14px;
    gap: 10px;
  }

  .word-row .col-rank,
  .word-row .col-tests,
  .word-row .col-freq,
  .word-row .col-status {
    display: none;
  }

  .word-row .col-lemma {
    grid-column: 1;
  }

  .word-row .col-bookmark {
    grid-column: 2;
  }

  .review-action-buttons {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 480px) {
  .detail-lemma-title {
    font-size: 28px;
  }

  .dna-connector-box {
    padding: 14px;
    gap: 8px;
  }

  .dna-chip {
    padding: 10px 14px;
    min-width: 80px;
  }

  .dna-chip-form {
    font-size: 15px;
  }
}

/* ==========================================================================
   VOCABULARY ENGINE V2 — INTERACTIVE LEARNING & QUIZ MODE EXTENSIONS
   Strictly Blue + Green + White + Slate Neutral
   ========================================================================== */

.pronounce-btn-group {
  display: inline-flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 8px;
}

.btn-audio-speak {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: var(--blue-subtle);
  border: 1px solid var(--blue-border);
  color: var(--blue-deep);
  font-size: 13px;
  font-weight: 700;
  padding: 6px 14px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.btn-audio-speak:hover {
  background: var(--blue-primary);
  color: #ffffff;
  border-color: var(--blue-primary);
  transform: translateY(-1px);
  box-shadow: 0 2px 8px var(--blue-glow);
}

.ipa-badge {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  color: var(--navy-dark);
  background: var(--bg-subtle);
  padding: 5px 12px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-light);
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.meaning-hero-card {
  margin-top: 14px;
  padding: 16px 18px;
  background: var(--blue-light);
  border: 1px solid var(--blue-border);
  border-left: 4px solid var(--blue-primary);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}

.meaning-content {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.meaning-label {
  font-size: 11px;
  font-weight: 800;
  color: var(--blue-deep);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.meaning-text-vi {
  font-size: 18px;
  font-weight: 700;
  color: var(--navy-dark);
  transition: filter var(--transition-fast);
}

.meaning-blurred {
  filter: blur(6px);
  user-select: none;
}

.btn-reveal-meaning {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 12px;
  font-weight: 700;
  color: var(--blue-primary);
  background: #ffffff;
  border: 1px solid var(--blue-border);
  padding: 6px 14px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  white-space: nowrap;
  transition: all var(--transition-fast);
}

.btn-reveal-meaning:hover {
  background: var(--blue-primary);
  color: #ffffff;
  border-color: var(--blue-primary);
}

/* Example Sentence & Synonyms */
.example-box {
  margin-top: 14px;
  padding: 14px 16px;
  background: var(--bg-subtle);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
}

.example-sentence-text {
  font-size: 15px;
  font-weight: 600;
  color: var(--navy-dark);
  line-height: 1.5;
  display: flex;
  align-items: center;
  gap: 8px;
}

.example-trans-text {
  font-size: 13px;
  color: var(--navy-muted);
  margin-top: 4px;
}

.thematic-tags-group {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 8px;
}

.thematic-tag {
  font-size: 12px;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: var(--radius-full);
  background: var(--blue-subtle);
  color: var(--blue-deep);
  border: 1px solid var(--blue-border);
}

.thematic-tag-antonym {
  background: #F1F5F9;
  color: #475569;
  border-color: #CBD5E1;
}

/* Quiz Mode Layout */
.quiz-wrapper {
  max-width: 820px;
  margin: 0 auto;
  width: 100%;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.quiz-header-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 14px 20px;
  box-shadow: var(--shadow-subtle);
}

.quiz-counter-text {
  font-size: 14px;
  font-weight: 700;
  color: var(--navy-dark);
}

.quiz-score-badge {
  font-size: 13px;
  font-weight: 700;
  color: var(--green-primary);
  background: var(--green-subtle);
  padding: 4px 10px;
  border-radius: var(--radius-full);
  border: 1px solid var(--green-border);
}

.quiz-main-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
  padding: 28px;
}

.quiz-type-pill {
  display: inline-flex;
  align-items: center;
  font-size: 11px;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding: 4px 12px;
  border-radius: var(--radius-full);
  background: var(--blue-subtle);
  color: var(--blue-deep);
  border: 1px solid var(--blue-border);
  margin-bottom: 16px;
}

.quiz-prompt-text {
  font-size: 19px;
  font-weight: 700;
  color: var(--navy-dark);
  line-height: 1.5;
  margin-bottom: 24px;
}

.quiz-options-group {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.quiz-option-button {
  display: flex;
  align-items: center;
  gap: 14px;
  width: 100%;
  text-align: left;
  padding: 14px 18px;
  background: var(--bg-subtle);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  font-size: 15px;
  font-weight: 600;
  color: var(--navy-dark);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.quiz-option-button:hover:not(:disabled) {
  background: var(--blue-subtle);
  border-color: var(--blue-border);
  color: var(--blue-deep);
  transform: translateX(3px);
}

.quiz-option-button.correct-choice {
  background: var(--green-subtle) !important;
  border-color: var(--green-primary) !important;
  color: var(--green-primary-hover) !important;
  font-weight: 700;
}

.quiz-option-button.incorrect-choice {
  background: #F8FAFC !important;
  border-color: #CBD5E1 !important;
  color: #64748B !important;
  opacity: 0.65;
}

.quiz-option-char {
  width: 30px;
  height: 30px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  background: #ffffff;
  border: 1px solid var(--border-light);
  font-size: 13px;
  font-weight: 800;
  color: var(--navy-slate);
  flex-shrink: 0;
}

.quiz-feedback-box {
  margin-top: 20px;
  padding: 18px;
  background: var(--green-light);
  border: 1px solid var(--green-border);
  border-left: 4px solid var(--green-primary);
  border-radius: var(--radius-md);
  font-size: 14px;
  line-height: 1.6;
  color: var(--navy-dark);
  animation: fadeIn 0.2s ease-in;
}

.quiz-controls-bar {
  display: flex;
  justify-content: flex-end;
  margin-top: 20px;
  padding-top: 18px;
  border-top: 1px solid var(--border-light);
}

.quiz-results-card {
  text-align: center;
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
  padding: 40px 24px;
}


/* ==========================================================================
   V3 BEGINNER-FIRST & GUIDED LEARNING EXPERIENCE ADDITIONS
   Strict Blue + Green + White + Slate Neutral Design Tokens
   ========================================================================== */

/* Topbar Badges & Streaks */
.vocab-badge-v3 {
  display: inline-block;
  font-size: 10px;
  font-weight: 800;
  letter-spacing: 0.05em;
  padding: 2px 7px;
  border-radius: 6px;
  background: var(--green-subtle);
  color: var(--green-primary-hover);
  border: 1px solid var(--green-border);
  vertical-align: middle;
  margin-left: 6px;
}

.topbar-streak-indicator {
  display: flex;
  align-items: center;
  gap: 6px;
  background: var(--bg-subtle);
  border: 1px solid var(--border-light);
  border-radius: 20px;
  padding: 5px 12px;
  font-size: 13px;
  font-weight: 700;
  color: var(--navy-dark);
}

.topbar-streak-indicator .streak-icon {
  font-size: 15px;
}

.btn-nav-highlight {
  background: var(--blue-light) !important;
  color: var(--blue-primary) !important;
  font-weight: 800 !important;
  border-color: var(--blue-border) !important;
}

/* Screen 1: Hero Guided Session Card */
.hero-session-card {
  background: var(--bg-surface);
  border: 1px solid var(--blue-border);
  border-radius: var(--radius-lg);
  padding: 28px 24px;
  box-shadow: 0 8px 28px -4px rgba(2, 132, 199, 0.08), 0 2px 8px -2px rgba(15, 23, 42, 0.04);
  margin-bottom: 20px;
  position: relative;
  overflow: hidden;
}

.hero-session-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--blue-primary) 0%, var(--green-primary) 100%);
}

.hero-session-badge-wrap {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 12px;
  flex-wrap: wrap;
}

.hero-pill-badge {
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 0.04em;
  padding: 4px 10px;
  border-radius: 20px;
  background: var(--blue-subtle);
  color: var(--blue-deep);
  border: 1px solid var(--blue-border);
}

.hero-time-badge {
  font-size: 12px;
  font-weight: 600;
  color: var(--navy-muted);
  background: var(--bg-subtle);
  padding: 4px 10px;
  border-radius: 20px;
  border: 1px solid var(--border-light);
}

.hero-session-title {
  font-size: 26px;
  font-weight: 800;
  color: var(--navy-dark);
  margin: 0 0 6px;
  line-height: 1.25;
}

.hero-session-sub {
  font-size: 14px;
  line-height: 1.5;
  color: var(--navy-muted);
  margin: 0 0 22px;
  max-width: 620px;
}

.hero-cta-wrap {
  margin-bottom: 16px;
}

.btn-hero-learn {
  width: 100%;
  min-height: 60px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 24px;
  background: linear-gradient(135deg, var(--blue-primary) 0%, #0369A1 100%);
  color: #FFFFFF;
  border: none;
  border-radius: 16px;
  cursor: pointer;
  box-shadow: 0 8px 24px -4px rgba(2, 132, 199, 0.38);
  transition: all 0.2s ease;
  text-decoration: none;
}

.btn-hero-learn:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 30px -4px rgba(2, 132, 199, 0.48);
}

.btn-hero-learn:active {
  transform: translateY(0);
}

.hero-btn-icon {
  font-size: 26px;
  margin-right: 12px;
}

.hero-btn-text {
  flex: 1;
  text-align: left;
  display: flex;
  flex-direction: column;
}

.hero-btn-text strong {
  font-size: 19px;
  font-weight: 800;
  letter-spacing: 0.02em;
}

.hero-btn-text small {
  font-size: 12px;
  font-weight: 500;
  opacity: 0.9;
  margin-top: 2px;
}

.hero-btn-arrow {
  font-size: 24px;
  font-weight: 700;
  transition: transform 0.2s;
}

.btn-hero-learn:hover .hero-btn-arrow {
  transform: translateX(4px);
}

.hero-secondary-actions {
  display: flex;
  gap: 10px;
}

.btn-subaction {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 16px;
  background: var(--bg-subtle);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  font-size: 14px;
  font-weight: 700;
  color: var(--navy-slate);
  cursor: pointer;
  transition: all 0.15s ease;
  min-height: 44px;
}

.btn-subaction:hover {
  background: var(--bg-subtle-hover);
  border-color: var(--blue-border);
  color: var(--blue-primary);
}

.subaction-count {
  font-size: 11px;
  font-weight: 700;
  padding: 2px 7px;
  border-radius: 12px;
  background: #FFFFFF;
  border: 1px solid var(--border-light);
  color: var(--navy-muted);
}

/* Preferences Switcher Bar */
.preferences-container {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 14px 18px;
  margin-bottom: 20px;
}

.pref-label {
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 0.04em;
  color: var(--navy-faint);
  text-transform: uppercase;
  margin-bottom: 8px;
}

.pref-pill-group {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.pref-pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 14px;
  border-radius: 20px;
  background: var(--bg-subtle);
  border: 1px solid var(--border-light);
  font-size: 13px;
  font-weight: 600;
  color: var(--navy-slate);
  cursor: pointer;
  transition: all 0.15s ease;
  min-height: 38px;
}

.pref-pill:hover {
  background: var(--bg-subtle-hover);
}

.pref-pill.active {
  background: var(--green-light);
  border-color: var(--green-border);
  color: var(--green-primary-hover);
  font-weight: 700;
}

.pref-status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: #94A3B8;
}

.pref-pill.active .pref-status-dot {
  background: var(--green-primary);
  box-shadow: 0 0 0 2px var(--green-border);
}

/* Milestone Preview Card */
.milestone-preview-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 20px 22px;
  margin-bottom: 20px;
  box-shadow: var(--shadow-subtle);
}

.milestone-preview-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 14px;
}

.milestone-label-tag {
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.05em;
  color: var(--blue-primary);
  text-transform: uppercase;
}

.milestone-card-title {
  font-size: 18px;
  font-weight: 800;
  color: var(--navy-dark);
  margin: 4px 0 2px;
}

.milestone-card-desc {
  font-size: 13px;
  color: var(--navy-muted);
  margin: 0;
}

.milestone-badge-count {
  font-size: 14px;
  font-weight: 800;
  color: var(--blue-primary);
  background: var(--blue-light);
  border: 1px solid var(--blue-border);
  padding: 4px 10px;
  border-radius: 12px;
  white-space: nowrap;
}

.milestone-prog-track {
  width: 100%;
  height: 8px;
  background: var(--bg-subtle);
  border-radius: 4px;
  overflow: hidden;
  margin-bottom: 12px;
}

.milestone-prog-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--blue-primary) 0%, var(--green-primary) 100%);
  border-radius: 4px;
  transition: width 0.3s ease;
}

.milestone-card-foot {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 12px;
  color: var(--navy-muted);
}

.btn-text-link {
  background: none;
  border: none;
  color: var(--blue-primary);
  font-weight: 700;
  font-size: 13px;
  cursor: pointer;
  padding: 4px 0;
}

.btn-text-link:hover {
  text-decoration: underline;
}

/* Home Topics Carousel */
.home-topics-section {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 18px 20px;
  margin-bottom: 20px;
}

.section-header-compact {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 12px;
}

.section-header-compact h3 {
  font-size: 16px;
  font-weight: 800;
  color: var(--navy-dark);
  margin: 0;
}

.topic-chips-carousel {
  display: flex;
  gap: 8px;
  overflow-x: auto;
  padding-bottom: 6px;
  scrollbar-width: thin;
}

.topic-chip {
  flex-shrink: 0;
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 7px 13px;
  border-radius: 20px;
  background: var(--bg-subtle);
  border: 1px solid var(--border-light);
  font-size: 13px;
  font-weight: 600;
  color: var(--navy-slate);
  cursor: pointer;
  transition: all 0.15s ease;
  white-space: nowrap;
}

.topic-chip:hover {
  border-color: var(--blue-border);
  color: var(--blue-primary);
}

.topic-chip.active {
  background: var(--blue-primary);
  color: #FFFFFF;
  border-color: var(--blue-primary);
  font-weight: 700;
}

/* Advanced Stats Collapsible */
.advanced-stats-collapse {
  margin-bottom: 30px;
}

.btn-collapse-toggle {
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 14px 18px;
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  font-size: 14px;
  font-weight: 700;
  color: var(--navy-slate);
  cursor: pointer;
  transition: background 0.15s ease;
}

.btn-collapse-toggle:hover {
  background: var(--bg-subtle);
}

.advanced-stats-body {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-top: none;
  border-radius: 0 0 var(--radius-md) var(--radius-md);
  padding: 20px;
  animation: fadeIn 0.2s ease-in;
}

.stats-overview-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 10px;
}

.stat-box {
  background: var(--bg-subtle);
  border-radius: var(--radius-sm);
  padding: 12px;
  text-align: center;
}

.stat-num {
  font-size: 20px;
  font-weight: 800;
  color: var(--blue-primary);
}

.stat-lbl {
  font-size: 11px;
  font-weight: 600;
  color: var(--navy-muted);
  margin-top: 2px;
}

.levels-compact-list {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.level-compact-row {
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  background: var(--bg-subtle);
  font-size: 13px;
  color: var(--navy-muted);
}

.level-compact-row.active {
  background: var(--blue-light);
  border-left: 3px solid var(--blue-primary);
  color: var(--navy-dark);
}

/* ==========================================================================
   Screen 2: Guided Daily Learning Session Styles
   ========================================================================== */
.session-wrapper {
  max-width: 640px;
  margin: 0 auto;
  padding: 10px 0 40px;
}

.session-top-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 12px;
}

.btn-session-exit {
  background: var(--bg-subtle);
  border: 1px solid var(--border-light);
  border-radius: 16px;
  padding: 6px 14px;
  font-size: 13px;
  font-weight: 600;
  color: var(--navy-muted);
  cursor: pointer;
  min-height: 38px;
}

.session-progress-info {
  display: flex;
  align-items: center;
  gap: 10px;
}

.session-step-text {
  font-size: 14px;
  font-weight: 800;
  color: var(--navy-dark);
}

.session-time-estimate {
  font-size: 12px;
  font-weight: 600;
  color: var(--navy-muted);
}

.session-mode-badge {
  font-size: 11px;
  font-weight: 700;
  padding: 3px 8px;
  border-radius: 10px;
  background: var(--green-subtle);
  color: var(--green-primary-hover);
  border: 1px solid var(--green-border);
}

.session-prog-track {
  width: 100%;
  height: 6px;
  background: var(--bg-subtle);
  border-radius: 3px;
  overflow: hidden;
  margin-bottom: 20px;
}

.session-prog-bar {
  height: 100%;
  background: linear-gradient(90deg, var(--blue-primary) 0%, var(--green-primary) 100%);
  border-radius: 3px;
  transition: width 0.3s ease;
}

.session-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: 20px;
  padding: 28px 24px;
  box-shadow: var(--shadow-card);
  animation: fadeIn 0.2s ease-in;
}

.session-card-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 16px;
}

.badge-milestone {
  font-size: 12px;
  font-weight: 700;
  color: var(--blue-primary);
  background: var(--blue-light);
  padding: 3px 10px;
  border-radius: 12px;
  border: 1px solid var(--blue-border);
}

.btn-card-save-star {
  background: none;
  border: 1px solid var(--border-light);
  border-radius: 14px;
  padding: 4px 10px;
  font-size: 12px;
  font-weight: 600;
  color: var(--navy-muted);
  cursor: pointer;
}

.btn-card-save-star.active {
  background: var(--blue-subtle);
  border-color: var(--blue-border);
  color: var(--blue-primary);
  font-weight: 800;
}

.session-word-hero {
  text-align: center;
  margin-bottom: 24px;
}

.session-lemma {
  font-size: 34px;
  font-weight: 800;
  color: var(--navy-dark);
  margin: 0 0 6px;
  letter-spacing: -0.01em;
}

.session-pos-row {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 8px;
  margin-bottom: 12px;
}

.session-ipa {
  font-family: var(--font-mono);
  font-size: 14px;
  color: var(--navy-faint);
}

.session-audio-row {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 10px;
  margin-top: 8px;
}

.btn-tts-speak {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  background: var(--blue-light);
  border: 1px solid var(--blue-border);
  color: var(--blue-primary);
  border-radius: 20px;
  padding: 6px 14px;
  font-size: 13px;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.15s ease;
  min-height: 38px;
}

.btn-tts-speak:hover {
  background: var(--blue-subtle);
}

.audio-tip-text {
  font-size: 12px;
  color: var(--navy-faint);
}

/* Guess Recall Box (Step 1) */
.guess-recall-box {
  background: var(--blue-light);
  border: 1.5px dashed var(--blue-border);
  border-radius: var(--radius-md);
  padding: 24px 20px;
  text-align: center;
  margin-bottom: 16px;
}

.guess-prompt-text {
  font-size: 16px;
  font-weight: 700;
  color: var(--navy-dark);
  margin-bottom: 16px;
}

.guess-btn-group {
  display: flex;
  gap: 10px;
  justify-content: center;
}

.btn-guess-action {
  padding: 12px 18px;
  border-radius: 12px;
  font-size: 14px;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.15s ease;
  min-height: 48px;
}

.btn-guess-reveal {
  background: var(--blue-primary);
  color: #FFFFFF;
  border: none;
  box-shadow: 0 4px 12px -2px rgba(2, 132, 199, 0.3);
}

.btn-guess-reveal:hover {
  background: var(--blue-deep);
}

.btn-guess-known {
  background: var(--bg-surface);
  color: var(--navy-dark);
  border: 1px solid var(--border-light);
}

.btn-guess-known:hover {
  background: var(--bg-subtle);
}

/* Revealed Content (Step 2 to 5) */
.revealed-content-box {
  opacity: 1;
}

.session-meaning-box {
  background: var(--bg-subtle);
  border-radius: var(--radius-md);
  padding: 18px 20px;
  text-align: center;
  margin-bottom: 14px;
}

.meaning-sublabel {
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.05em;
  color: var(--navy-faint);
  text-transform: uppercase;
  margin-bottom: 4px;
}

.session-meaning-vi {
  font-size: 22px;
  font-weight: 800;
  color: var(--navy-dark);
  line-height: 1.35;
}

.session-why-box {
  display: flex;
  align-items: center;
  gap: 10px;
  background: var(--green-light);
  border: 1px solid var(--green-border);
  border-radius: var(--radius-sm);
  padding: 12px 16px;
  font-size: 13px;
  color: var(--navy-slate);
  margin-bottom: 16px;
}

.why-icon {
  font-size: 16px;
}

.session-chunk-box {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-left: 4px solid var(--blue-primary);
  border-radius: var(--radius-sm);
  padding: 14px 16px;
  margin-bottom: 16px;
}

.chunk-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 6px;
}

.chunk-label {
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.04em;
  color: var(--navy-muted);
}

.chunk-badge {
  font-size: 10px;
  font-weight: 800;
  color: var(--blue-primary);
  background: var(--blue-light);
  padding: 2px 6px;
  border-radius: 8px;
}

.chunk-phrase {
  font-size: 16px;
  font-weight: 700;
  color: var(--navy-dark);
}

.btn-toggle-more-collocs {
  background: none;
  border: none;
  font-size: 12px;
  font-weight: 700;
  color: var(--blue-primary);
  cursor: pointer;
  padding: 6px 0 0;
  display: block;
}

.more-collocations-wrap {
  margin-top: 10px;
  padding-top: 10px;
  border-top: 1px dashed var(--border-light);
}

.more-collocs-list {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.colloc-item-sub {
  font-size: 13px;
  color: var(--navy-slate);
  padding: 4px 0;
}

/* Contrast & Trick Box */
.session-contrast-box {
  background: var(--bg-subtle);
  border-radius: var(--radius-md);
  padding: 16px;
  margin-bottom: 20px;
}

.contrast-header {
  font-size: 13px;
  font-weight: 800;
  color: var(--navy-dark);
  margin-bottom: 10px;
}

.affix-trick-banner {
  display: flex;
  align-items: center;
  gap: 8px;
  background: var(--blue-light);
  border: 1px solid var(--blue-border);
  border-radius: var(--radius-sm);
  padding: 10px 14px;
  font-size: 13px;
  font-weight: 600;
  color: var(--navy-slate);
  margin-bottom: 12px;
}

.mini-q-stem {
  font-size: 15px;
  font-weight: 700;
  color: var(--navy-dark);
  margin-bottom: 10px;
  line-height: 1.4;
}

.mini-q-options {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.mini-q-opt-btn {
  background: #FFFFFF;
  border: 1px solid var(--border-light);
  border-radius: var(--radius-sm);
  padding: 10px 14px;
  font-size: 14px;
  font-weight: 600;
  color: var(--navy-slate);
  text-align: left;
  cursor: pointer;
  transition: all 0.15s ease;
  min-height: 42px;
}

.mini-q-opt-btn:hover {
  border-color: var(--blue-border);
}

.mini-q-opt-btn.correct {
  background: var(--green-subtle) !important;
  border-color: var(--green-primary) !important;
  color: var(--green-primary-hover) !important;
  font-weight: 800;
}

.mini-q-opt-btn.wrong {
  background: #F8FAFC !important;
  border-color: #CBD5E1 !important;
  color: #94A3B8 !important;
  opacity: 0.7;
}

.mini-q-feedback {
  margin-top: 10px;
  padding: 10px 14px;
  border-radius: var(--radius-sm);
  background: var(--green-light);
  border: 1px solid var(--green-border);
  font-size: 13px;
  color: var(--navy-dark);
  line-height: 1.45;
}

/* Memory Self Rating */
.session-memory-rating-area {
  padding-top: 18px;
  border-top: 1px solid var(--border-light);
  margin-bottom: 16px;
}

.rating-label {
  font-size: 13px;
  font-weight: 800;
  color: var(--navy-dark);
  margin-bottom: 10px;
  text-align: center;
}

.memory-rating-buttons {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 8px;
}

.btn-mem-rate {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 12px 6px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-light);
  background: #FFFFFF;
  cursor: pointer;
  transition: all 0.15s ease;
  min-height: 58px;
}

.btn-mem-rate:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-subtle);
}

.mem-emoji {
  font-size: 20px;
  margin-bottom: 2px;
}

.mem-text {
  font-size: 12px;
  font-weight: 700;
  color: var(--navy-dark);
}

.btn-mem-again:hover {
  border-color: #94A3B8;
  background: #F1F5F9;
}

.btn-mem-hard:hover {
  border-color: var(--blue-border);
  background: var(--blue-light);
}

.btn-mem-good:hover {
  border-color: var(--green-border);
  background: var(--green-light);
}

.btn-mem-mastered:hover {
  border-color: var(--green-primary);
  background: var(--green-subtle);
}

/* Progressive Disclosure (Hiểu thêm về từ này) */
.deep-detail-disclosure {
  padding-top: 14px;
  border-top: 1px dashed var(--border-light);
}

.btn-deep-disclosure {
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: none;
  border: none;
  font-size: 13px;
  font-weight: 700;
  color: var(--blue-primary);
  cursor: pointer;
  padding: 8px 0;
}

.btn-deep-disclosure:hover {
  text-decoration: underline;
}

.deep-detail-body {
  margin-top: 14px;
  display: flex;
  flex-direction: column;
  gap: 14px;
  animation: fadeIn 0.2s ease-in;
}

.deep-subcard {
  background: var(--bg-subtle);
  border-radius: var(--radius-sm);
  padding: 14px;
}

.deep-subcard h4 {
  font-size: 13px;
  font-weight: 800;
  color: var(--navy-dark);
  margin: 0 0 8px;
}

/* ==========================================================================
   Screen 3: Session Complete Styles
   ========================================================================== */
.complete-wrapper {
  max-width: 520px;
  margin: 20px auto 40px;
}

.complete-card {
  background: var(--bg-surface);
  border: 1px solid var(--green-border);
  border-radius: 24px;
  padding: 40px 24px;
  text-align: center;
  box-shadow: var(--shadow-card);
}

.complete-celebrate-icon {
  font-size: 48px;
  margin-bottom: 10px;
}

.complete-badge {
  display: inline-block;
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.05em;
  padding: 4px 10px;
  border-radius: 12px;
  background: var(--green-subtle);
  color: var(--green-primary-hover);
  margin-bottom: 12px;
}

.complete-title {
  font-size: 26px;
  font-weight: 800;
  color: var(--navy-dark);
  margin: 0 0 6px;
}

.complete-subtitle {
  font-size: 14px;
  color: var(--navy-muted);
  margin: 0 0 24px;
}

.complete-metrics-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 10px;
  margin-bottom: 28px;
}

.metric-card {
  background: var(--bg-subtle);
  border-radius: var(--radius-md);
  padding: 14px 10px;
}

.metric-val {
  font-size: 22px;
  font-weight: 800;
  color: var(--blue-primary);
}

.metric-lbl {
  font-size: 11px;
  font-weight: 600;
  color: var(--navy-muted);
  margin-top: 4px;
  line-height: 1.3;
}

.complete-actions {
  display: flex;
  gap: 12px;
  justify-content: center;
}

.btn-large {
  padding: 14px 24px;
  font-size: 15px;
  font-weight: 800;
  border-radius: 14px;
  min-height: 50px;
}

/* ==========================================================================
   Screen 4: Quick Review (Flashcard V3)
   ========================================================================== */
.review-wrapper {
  max-width: 580px;
  margin: 0 auto;
  padding: 10px 0 40px;
}

.review-header-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 16px;
}

.review-header-bar h2 {
  font-size: 22px;
  font-weight: 800;
  color: var(--navy-dark);
  margin: 0;
}

.review-header-bar p {
  font-size: 13px;
  color: var(--navy-muted);
  margin: 2px 0 0;
}

.review-queue-badge {
  font-size: 13px;
  font-weight: 800;
  color: var(--blue-primary);
  background: var(--blue-light);
  border: 1px solid var(--blue-border);
  padding: 4px 10px;
  border-radius: 12px;
}

.flashcard-card-v3 {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: 20px;
  padding: 28px 24px;
  box-shadow: var(--shadow-card);
}

.flashcard-meta-row {
  display: flex;
  justify-content: space-between;
  margin-bottom: 16px;
}

.flashcard-tier-pill {
  font-size: 12px;
  font-weight: 700;
  color: var(--blue-primary);
  background: var(--blue-light);
  padding: 3px 8px;
  border-radius: 10px;
}

.flashcard-pos-pill {
  font-size: 12px;
  font-weight: 700;
  color: var(--navy-slate);
  background: var(--bg-subtle);
  padding: 3px 8px;
  border-radius: 10px;
}

.flashcard-front-center {
  text-align: center;
  padding: 20px 0;
}

.flashcard-word-title {
  font-size: 36px;
  font-weight: 800;
  color: var(--navy-dark);
  margin: 0 0 10px;
}

.flashcard-audio-btns {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 10px;
  margin-bottom: 14px;
}

.qr-ipa-text {
  font-family: var(--font-mono);
  font-size: 14px;
  color: var(--navy-faint);
}

.qr-guess-tip {
  font-size: 13px;
  color: var(--navy-muted);
  margin-bottom: 20px;
}

.btn-reveal-solution {
  background: var(--blue-primary);
  color: #FFFFFF;
  border: none;
  border-radius: 12px;
  padding: 12px 24px;
  font-size: 15px;
  font-weight: 700;
  cursor: pointer;
  box-shadow: 0 4px 14px -2px rgba(2, 132, 199, 0.3);
  transition: all 0.15s ease;
  min-height: 48px;
}

.btn-reveal-solution:hover {
  background: var(--blue-deep);
}

.flashcard-back-v3 {
  border-top: 1px dashed var(--border-light);
  padding-top: 20px;
  text-align: center;
  animation: fadeIn 0.2s ease-in;
}

.qr-back-meaning {
  font-size: 22px;
  font-weight: 800;
  color: var(--navy-dark);
  margin-bottom: 12px;
}

.qr-back-chunk {
  font-size: 15px;
  color: var(--navy-slate);
  background: var(--bg-subtle);
  padding: 10px 14px;
  border-radius: 8px;
  margin-bottom: 10px;
}

.qr-back-trick {
  font-size: 13px;
  color: var(--navy-muted);
  margin-bottom: 20px;
}

.qr-rating-row {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 8px;
}

/* ==========================================================================
   Screen 5: Milestones & Learning Path
   ========================================================================== */
.milestones-view-wrapper {
  max-width: 900px;
  margin: 0 auto;
  padding-bottom: 40px;
}

.milestones-top-desc h2 {
  font-size: 24px;
  font-weight: 800;
  color: var(--navy-dark);
  margin: 0 0 4px;
}

.milestones-top-desc p {
  font-size: 14px;
  color: var(--navy-muted);
  margin: 0 0 18px;
}

.milestones-nav-bar {
  display: flex;
  gap: 10px;
  overflow-x: auto;
  padding-bottom: 8px;
  margin-bottom: 20px;
  scrollbar-width: thin;
}

.milestone-step-btn {
  flex-shrink: 0;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  padding: 12px 16px;
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all 0.15s ease;
  min-width: 140px;
}

.milestone-step-btn.active {
  background: var(--blue-light);
  border-color: var(--blue-border);
  box-shadow: 0 4px 12px -2px rgba(2, 132, 199, 0.15);
}

.milestone-step-btn.locked-soft {
  opacity: 0.75;
}

.m-step-num {
  font-size: 11px;
  font-weight: 800;
  color: var(--navy-faint);
  text-transform: uppercase;
}

.milestone-step-btn.active .m-step-num {
  color: var(--blue-primary);
}

.m-step-title {
  font-size: 15px;
  font-weight: 800;
  color: var(--navy-dark);
  margin: 2px 0 4px;
}

.m-step-badge {
  font-size: 10px;
  font-weight: 700;
  padding: 2px 6px;
  border-radius: 8px;
  background: var(--bg-subtle);
  color: var(--navy-muted);
}

.milestone-step-btn.active .m-step-badge {
  background: var(--blue-primary);
  color: #FFFFFF;
}

.milestone-info-banner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: var(--blue-light);
  border: 1px solid var(--blue-border);
  border-radius: var(--radius-md);
  padding: 18px 20px;
  margin-bottom: 18px;
}

.m-info-text h3 {
  font-size: 17px;
  font-weight: 800;
  color: var(--navy-dark);
  margin: 0 0 4px;
}

.m-info-text p {
  font-size: 13px;
  color: var(--navy-slate);
  margin: 0;
  max-width: 600px;
}

.m-info-stat {
  font-size: 14px;
  font-weight: 800;
  color: var(--blue-primary);
  background: #FFFFFF;
  padding: 6px 12px;
  border-radius: 12px;
  border: 1px solid var(--blue-border);
  white-space: nowrap;
}

.milestone-controls-row {
  display: flex;
  gap: 12px;
  margin-bottom: 18px;
  flex-wrap: wrap;
}

/* Learner Cards Grid (Zero table feel!) */
.learner-cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 14px;
}

.learner-word-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 16px 18px;
  box-shadow: var(--shadow-subtle);
  cursor: pointer;
  transition: all 0.15s ease;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.learner-word-card:hover {
  transform: translateY(-2px);
  border-color: var(--blue-border);
  box-shadow: var(--shadow-card);
}

.card-top-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 8px;
}

.card-lemma-title {
  font-size: 18px;
  font-weight: 800;
  color: var(--navy-dark);
}

.card-audio-btn {
  background: var(--blue-light);
  border: 1px solid var(--blue-border);
  border-radius: 12px;
  padding: 2px 8px;
  font-size: 11px;
  font-weight: 700;
  color: var(--blue-primary);
  cursor: pointer;
}

.card-meaning-text {
  font-size: 14px;
  font-weight: 600;
  color: var(--navy-slate);
  margin-bottom: 12px;
  line-height: 1.4;
}

.card-foot-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 12px;
  padding-top: 10px;
  border-top: 1px solid var(--border-light);
}

.card-status-pill {
  font-size: 11px;
  font-weight: 700;
  padding: 2px 8px;
  border-radius: 10px;
  background: var(--bg-subtle);
  color: var(--navy-muted);
}

.card-status-pill.status-mastered {
  background: var(--green-subtle);
  color: var(--green-primary-hover);
}

.card-status-pill.status-learning {
  background: var(--blue-subtle);
  color: var(--blue-deep);
}

.card-save-star {
  font-size: 16px;
  color: #94A3B8;
  cursor: pointer;
}

.card-save-star.saved {
  color: #F59E0B;
}

/* ==========================================================================
   Screen 6: Topic Explorer Styles
   ========================================================================== */
.topics-view-wrapper {
  max-width: 900px;
  margin: 0 auto;
  padding-bottom: 40px;
}

.topics-header h2 {
  font-size: 24px;
  font-weight: 800;
  color: var(--navy-dark);
  margin: 0 0 4px;
}

.topics-header p {
  font-size: 14px;
  color: var(--navy-muted);
  margin: 0 0 20px;
}

.topics-grid-selector {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(130px, 1fr));
  gap: 10px;
  margin-bottom: 24px;
}

.topic-select-btn {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 14px 10px;
  text-align: center;
  cursor: pointer;
  transition: all 0.15s ease;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
}

.topic-select-btn:hover {
  border-color: var(--blue-border);
  background: var(--blue-light);
}

.topic-select-btn.active {
  background: var(--blue-primary);
  border-color: var(--blue-primary);
  color: #FFFFFF;
}

.topic-btn-icon {
  font-size: 22px;
}

.topic-btn-label {
  font-size: 13px;
  font-weight: 700;
}

.topic-words-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 14px;
}

.topic-words-header h3 {
  font-size: 18px;
  font-weight: 800;
  color: var(--navy-dark);
  margin: 0;
}

.topic-words-count {
  font-size: 13px;
  font-weight: 700;
  color: var(--blue-primary);
}

/* ==========================================================================
   Screen 7: Saved Words Styles
   ========================================================================== */
.saved-wrapper {
  max-width: 900px;
  margin: 0 auto;
  padding-bottom: 40px;
}

.saved-header h2 {
  font-size: 24px;
  font-weight: 800;
  color: var(--navy-dark);
  margin: 0 0 4px;
}

.saved-header p {
  font-size: 14px;
  color: var(--navy-muted);
  margin: 0 0 20px;
}

.empty-state-card {
  text-align: center;
  padding: 40px 20px;
  background: var(--bg-surface);
  border: 1px dashed var(--border-light);
  border-radius: var(--radius-lg);
  color: var(--navy-muted);
}

.empty-state-icon {
  font-size: 36px;
  margin-bottom: 10px;
}

.empty-state-title {
  font-size: 17px;
  font-weight: 800;
  color: var(--navy-dark);
  margin-bottom: 6px;
}

/* Mobile Highlight in bottom bar */
.btn-mob-highlight {
  color: var(--blue-primary) !important;
}

.btn-mob-highlight svg {
  stroke: var(--blue-primary) !important;
}

/* ==========================================================================
   V3.1 RESTORE LEARNING VALUE — QUICK REVIEW CARD REFINEMENT
   Order: WORD -> POS (Bilingual) -> IPA/Audio -> MEANING -> FAMILY -> COLLOCATIONS -> RATING
   ========================================================================== */

.flashcard-header-block {
  text-align: center;
  margin-bottom: 16px;
}

.flashcard-pos-bilingual {
  display: inline-block;
  font-size: 13px;
  font-weight: 800;
  letter-spacing: 0.04em;
  padding: 4px 14px;
  border-radius: 16px;
  background: var(--blue-light);
  border: 1px solid var(--blue-border);
  color: var(--blue-deep);
  margin: 6px 0 10px;
}

.flashcard-front-prompt-box {
  text-align: center;
  padding: 16px 0;
}

.qr-meaning-block {
  background: var(--bg-subtle);
  border-radius: var(--radius-md);
  padding: 14px 18px;
  text-align: center;
  margin-bottom: 12px;
}

.qr-block-label {
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.05em;
  color: var(--navy-faint);
  text-transform: uppercase;
  margin-bottom: 4px;
}

.qr-block-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 8px;
}

.qr-block-hint {
  font-size: 11px;
  color: var(--navy-faint);
}

.qr-family-block {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 12px 14px;
  margin-bottom: 12px;
}

.qr-family-items {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.qr-family-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: var(--bg-subtle);
  padding: 8px 12px;
  border-radius: 8px;
  font-size: 13px;
  cursor: pointer;
  transition: all 0.15s ease;
  border: 1px solid transparent;
}

.qr-family-row:hover {
  background: var(--blue-light);
  border-color: var(--blue-border);
}

.qr-fam-left {
  display: flex;
  align-items: center;
  gap: 6px;
}

.qr-fam-word {
  font-weight: 800;
  color: var(--blue-primary);
}

.qr-fam-pos {
  font-size: 11px;
  font-weight: 700;
  color: var(--navy-slate);
  background: #FFFFFF;
  border: 1px solid var(--border-light);
  padding: 1px 6px;
  border-radius: 6px;
}

.qr-fam-meaning {
  font-size: 12px;
  color: var(--navy-muted);
}

.qr-colloc-block {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 12px 14px;
  margin-bottom: 16px;
}

.qr-colloc-items {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.qr-colloc-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: var(--bg-subtle);
  padding: 8px 12px;
  border-radius: 8px;
  font-size: 13px;
}

.qr-colloc-phrase {
  font-weight: 700;
  color: var(--navy-dark);
}

.qr-colloc-arrow {
  color: var(--blue-primary);
  font-weight: 700;
  margin: 0 6px;
}

.qr-colloc-trans {
  color: var(--navy-muted);
  font-size: 12px;
}

.btn-toggle-extra-family,
.btn-toggle-extra-collocs {
  background: none;
  border: none;
  font-size: 12px;
  font-weight: 700;
  color: var(--blue-primary);
  cursor: pointer;
  padding: 6px 0 0;
  display: block;
}

.btn-toggle-extra-family:hover,
.btn-toggle-extra-collocs:hover {
  text-decoration: underline;
}

.qr-rating-area {
  margin-top: 14px;
  padding-top: 14px;
  border-top: 1px solid var(--border-light);
}

.qr-rating-label {
  font-size: 13px;
  font-weight: 800;
  color: var(--navy-dark);
  text-align: center;
  margin-bottom: 10px;
}

@media (max-width: 480px) {
  .flashcard-card-v3 {
    padding: 16px 14px;
    margin-bottom: 90px; /* Space above fixed bottom navigation */
  }

  .flashcard-header-block {
    margin-bottom: 10px;
  }

  .flashcard-word-title {
    font-size: 28px;
    margin-bottom: 2px;
  }

  .flashcard-pos-bilingual {
    font-size: 11px;
    padding: 3px 10px;
    margin: 4px 0 6px;
  }

  .flashcard-audio-btns {
    margin-bottom: 4px;
    gap: 6px;
  }

  .qr-meaning-block {
    padding: 10px 12px;
    margin-bottom: 10px;
  }

  .qr-back-meaning {
    font-size: 17px;
  }

  .qr-family-block,
  .qr-colloc-block {
    padding: 10px 12px;
    margin-bottom: 10px;
  }

  .qr-family-items,
  .qr-colloc-items {
    gap: 5px;
  }

  .qr-family-row,
  .qr-colloc-row {
    padding: 6px 10px;
    font-size: 12px;
    flex-wrap: wrap;
    gap: 4px;
  }

  .qr-rating-area {
    margin-top: 10px;
    padding-top: 10px;
  }

  .qr-rating-label {
    font-size: 12px;
    margin-bottom: 8px;
  }

  .qr-rating-row {
    gap: 6px;
  }

  .btn-mem-rate {
    padding: 8px 4px;
  }

  .btn-mem-rate .mem-emoji {
    font-size: 18px;
  }

  .btn-mem-rate .mem-text {
    font-size: 11px;
  }
}