/* =====================================================================
   GMAT 750+ Trainer - Global Stylesheet
   Design tokens, theming (light/dark), layout, components, responsive
   ===================================================================== */

/* ---------- Design Tokens (Light Theme default) ---------- */
:root {
  --color-primary: #1A237E;        /* Deep Navy */
  --color-secondary: #0D47A1;      /* Royal Blue */
  --color-accent: #FF6F00;         /* Amber */
  --color-success: #2E7D32;
  --color-danger: #C62828;
  --color-bg: #F5F7FA;
  --color-card: #FFFFFF;
  --color-text: #1A2332;
  --color-muted: #546E7A;
  --color-border: #E2E8F0;
  --color-chart-grid: rgba(26, 35, 50, 0.08);
  --shadow-card: 0 2px 8px rgba(26, 35, 50, 0.06);
  --shadow-card-hover: 0 6px 20px rgba(26, 35, 50, 0.12);
  --shadow-header: 0 1px 4px rgba(26, 35, 50, 0.08);
  --header-bg: rgba(245, 247, 250, 0.9);
  --radius: 12px;
  --radius-sm: 8px;
  --font-heading: 'Inter', sans-serif;
  --font-body: 'Open Sans', sans-serif;
}

/* ---------- Dark Theme Tokens ---------- */
[data-theme="dark"] {
  --color-primary: #8C9EFF;        /* lighter navy for contrast on dark */
  --color-secondary: #82B1FF;
  --color-accent: #FF8F00;
  --color-success: #66BB6A;
  --color-danger: #EF5350;
  --color-bg: #121826;
  --color-card: #1C2333;
  --color-text: #E8EDF5;
  --color-muted: #9AA7B8;
  --color-border: #2B3448;
  --color-chart-grid: rgba(232, 237, 245, 0.1);
  --shadow-card: 0 2px 8px rgba(0, 0, 0, 0.4);
  --shadow-card-hover: 0 6px 20px rgba(0, 0, 0, 0.5);
  --shadow-header: 0 1px 4px rgba(0, 0, 0, 0.4);
  --header-bg: rgba(18, 24, 38, 0.9);
}

/* ---------- Reset & Base ---------- */
* { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  font-family: var(--font-body);
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.6;
  transition: background 0.3s ease, color 0.3s ease;
  min-height: 100vh;
}

h1, h2, h3, h4, h5, h6 { font-family: var(--font-heading); color: var(--color-text); line-height: 1.3; }
a { color: var(--color-secondary); text-decoration: none; }
a:hover { color: var(--color-primary); }
button { font-family: var(--font-body); cursor: pointer; }

/* Accessible focus states */
:focus-visible {
  outline: 3px solid var(--color-accent);
  outline-offset: 2px;
  border-radius: 4px;
}

/* ---------- Header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--header-bg);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--color-border);
  box-shadow: var(--shadow-header);
}

.header-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0.75rem 1.25rem;
  display: flex;
  align-items: center;
  gap: 1rem;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-heading);
  font-weight: 800;
  color: var(--color-text);
  white-space: nowrap;
}
.brand-mark { font-size: 1.4rem; }
.brand-highlight { color: var(--color-accent); }
.brand-text { font-size: 1.05rem; }

.main-nav {
  display: flex;
  gap: 0.25rem;
  margin-left: auto;
  flex-wrap: wrap;
}
.nav-link {
  padding: 0.5rem 0.75rem;
  border-radius: var(--radius-sm);
  color: var(--color-muted);
  font-weight: 600;
  font-size: 0.9rem;
  transition: background 0.2s, color 0.2s;
}
.nav-link:hover { background: rgba(13, 71, 161, 0.08); color: var(--color-primary); }
.nav-link.active { background: var(--color-primary); color: #fff; }

.header-stats {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-size: 0.82rem;
  color: var(--color-muted);
  font-weight: 600;
}
.header-stat {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  background: var(--color-card);
  padding: 0.3rem 0.6rem;
  border-radius: 999px;
  border: 1px solid var(--color-border);
}

.theme-toggle {
  background: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: 999px;
  width: 38px;
  height: 38px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  transition: transform 0.2s;
}
.theme-toggle:hover { transform: rotate(15deg); }

.hamburger {
  display: none;
  background: none;
  border: none;
  flex-direction: column;
  gap: 5px;
  padding: 8px;
}
.hamburger span {
  width: 24px; height: 3px;
  background: var(--color-text);
  border-radius: 2px;
  transition: 0.3s;
}
.hamburger.open span:nth-child(1) { transform: translateY(8px) rotate(45deg); }
.hamburger.open span:nth-child(2) { opacity: 0; }
.hamburger.open span:nth-child(3) { transform: translateY(-8px) rotate(-45deg); }

/* ---------- Main layout ---------- */
.main-content { min-height: calc(100vh - 70px); }
.app-view {
  max-width: 1200px;
  margin: 0 auto;
  padding: 1.5rem 1.25rem 4rem;
}
.app-view.hidden { display: none; }

/* ---------- Cards & sections ---------- */
.card {
  background: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-card);
  padding: 1.5rem;
  margin-bottom: 1.25rem;
  transition: box-shadow 0.2s, transform 0.2s;
}
.card-hover:hover { box-shadow: var(--shadow-card-hover); transform: translateY(-2px); }

.card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 1rem;
  flex-wrap: wrap;
}
.card-title {
  font-size: 1.15rem;
  font-weight: 700;
}
.card-subtitle { color: var(--color-muted); font-size: 0.9rem; }

/* ---------- Grid layouts ---------- */
.grid { display: grid; gap: 1.25rem; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.6rem 1.1rem;
  border-radius: var(--radius-sm);
  border: 2px solid transparent;
  font-weight: 600;
  font-size: 0.92rem;
  transition: all 0.2s;
  background: var(--color-secondary);
  color: #fff;
}
.btn:hover { filter: brightness(1.1); transform: translateY(-1px); }
.btn:active { transform: translateY(0); }
.btn-primary { background: var(--color-primary); color: #fff; }
.btn-accent { background: var(--color-accent); color: #fff; }
.btn-success { background: var(--color-success); color: #fff; }
.btn-danger { background: var(--color-danger); color: #fff; }
.btn-outline {
  background: transparent;
  color: var(--color-secondary);
  border-color: var(--color-secondary);
}
.btn-outline:hover { background: var(--color-secondary); color: #fff; }
.btn-ghost { background: transparent; color: var(--color-muted); border-color: var(--color-border); }
.btn-ghost:hover { color: var(--color-text); border-color: var(--color-muted); }
.btn-sm { padding: 0.35rem 0.7rem; font-size: 0.8rem; }
.btn-lg { padding: 0.8rem 1.6rem; font-size: 1rem; }
.btn-block { width: 100%; }
.btn:disabled { opacity: 0.5; cursor: not-allowed; transform: none; }

/* ---------- Badges / chips ---------- */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  padding: 0.2rem 0.6rem;
  border-radius: 999px;
  font-size: 0.75rem;
  font-weight: 700;
  background: var(--color-border);
  color: var(--color-muted);
}
.badge-easy { background: rgba(46, 125, 50, 0.15); color: var(--color-success); }
.badge-medium { background: rgba(255, 111, 0, 0.15); color: var(--color-accent); }
.badge-hard { background: rgba(198, 40, 40, 0.15); color: var(--color-danger); }
.badge-primary { background: var(--color-primary); color: #fff; }
.badge-accent { background: var(--color-accent); color: #fff; }
.badge-success { background: var(--color-success); color: #fff; }
.badge-section { color: #fff; }

/* ---------- Forms ---------- */
.field { margin-bottom: 1rem; }
.field label {
  display: block;
  font-weight: 600;
  margin-bottom: 0.35rem;
  font-size: 0.9rem;
}
.field input:not([type=checkbox]):not([type=radio]),
.field select,
.field textarea {
  width: 100%;
  padding: 0.6rem 0.8rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-body);
  font-size: 0.95rem;
  transition: border-color 0.2s;
}
.field input:not([type=checkbox]):focus,
.field select:focus,
.field textarea:focus {
  outline: none;
  border-color: var(--color-secondary);
}
.field input[type=range] { padding: 0; border: none; }
.field-hint { font-size: 0.8rem; color: var(--color-muted); margin-top: 0.25rem; }

/* ---------- Progress bars ---------- */
.progress {
  background: var(--color-border);
  border-radius: 999px;
  height: 10px;
  overflow: hidden;
  width: 100%;
}
.progress-bar {
  height: 100%;
  background: linear-gradient(90deg, var(--color-primary), var(--color-accent));
  border-radius: 999px;
  transition: width 0.5s ease;
}
.progress-bar-success { background: var(--color-success); }
.progress-bar-accent { background: var(--color-accent); }

/* ---------- Stats & metrics ---------- */
.stat-row { display: flex; gap: 1rem; flex-wrap: wrap; }
.stat-block {
  flex: 1 1 150px;
  text-align: center;
  padding: 1rem;
  background: var(--color-bg);
  border-radius: var(--radius);
  border: 1px solid var(--color-border);
}
.stat-value { font-family: var(--font-heading); font-size: 1.6rem; font-weight: 800; color: var(--color-primary); }
.stat-label { font-size: 0.8rem; color: var(--color-muted); text-transform: uppercase; letter-spacing: 0.5px; }

/* ---------- Lists & feeds ---------- */
.feed-item {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.7rem 0;
  border-bottom: 1px solid var(--color-border);
  font-size: 0.9rem;
}
.feed-item:last-child { border-bottom: none; }
.feed-icon { font-size: 1.2rem; }
.feed-time { margin-left: auto; color: var(--color-muted); font-size: 0.75rem; white-space: nowrap; }

/* ---------- Topics / Learn ---------- */
.section-tab {
  display: flex;
  gap: 0.5rem;
  margin-bottom: 1.5rem;
  flex-wrap: wrap;
}
.section-tab-btn {
  padding: 0.6rem 1.2rem;
  border-radius: var(--radius-sm);
  border: 2px solid var(--color-border);
  background: var(--color-card);
  color: var(--color-text);
  font-weight: 700;
}
.section-tab-btn.active {
  border-color: var(--color-primary);
  color: var(--color-primary);
  background: rgba(26, 35, 126, 0.06);
}
.section-tab-btn .tab-icon { margin-right: 0.35rem; }

.topic-card {
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
  height: 100%;
}
.topic-name { font-weight: 700; font-size: 1rem; }
.topic-meta { font-size: 0.82rem; color: var(--color-muted); }
.topic-progress { margin-top: auto; }
.topic-state { display: flex; gap: 0.35rem; align-items: center; font-size: 0.8rem; }
.topic-card.topic-due { border-left: 3px solid var(--color-primary); }

.lesson-container { max-width: 780px; margin: 0 auto; }
.lesson-section { margin-bottom: 1.75rem; }
.lesson-section h3 { margin-bottom: 0.75rem; font-size: 1.25rem; }
.lesson-section p { margin-bottom: 0.75rem; }
.lesson-box {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-left: 4px solid var(--color-secondary);
  padding: 1rem;
  border-radius: var(--radius-sm);
  margin: 0.85rem 0;
}
.lesson-box-tip { border-left-color: var(--color-accent); }
.lesson-box-danger { border-left-color: var(--color-danger); }
.lesson-box-success { border-left-color: var(--color-success); }
.formula-table { width: 100%; border-collapse: collapse; margin: 0.85rem 0; }
.formula-table th, .formula-table td {
  border: 1px solid var(--color-border);
  padding: 0.6rem 0.8rem;
  text-align: left;
  font-size: 0.9rem;
}
.formula-table th { background: var(--color-bg); font-weight: 700; }
.formula-table tr:nth-child(even) td { background: rgba(0,0,0,0.02); }

.example-block {
  background: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1rem;
  margin: 0.85rem 0;
}
.example-question { font-weight: 600; margin-bottom: 0.5rem; }
.example-reason { color: var(--color-muted); font-size: 0.9rem; margin-top: 0.5rem; }
.example-answer { color: var(--color-success); font-weight: 700; }

/* ---------- Practice ---------- */
.mode-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); gap: 1rem; }
.mode-card {
  text-align: left;
  background: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1.25rem;
  cursor: pointer;
  transition: all 0.2s;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}
.mode-card:hover { box-shadow: var(--shadow-card-hover); transform: translateY(-2px); border-color: var(--color-secondary); }
.mode-icon { font-size: 1.6rem; }
.mode-title { font-weight: 700; font-size: 1rem; }
.mode-desc { font-size: 0.85rem; color: var(--color-muted); }

.question-view { max-width: 780px; margin: 0 auto; }
.question-topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  flex-wrap: wrap;
  margin-bottom: 1rem;
}
.timer-display {
  font-family: var(--font-heading);
  font-size: 1.15rem;
  font-weight: 700;
  padding: 0.3rem 0.7rem;
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
}
.timer-display.warning { color: var(--color-accent); }
.timer-display.danger { color: var(--color-danger); animation: pulse 1s infinite; }
@keyframes pulse { 0%,100% {opacity:1;} 50% {opacity:0.5;} }

.question-text {
  font-size: 1.05rem;
  font-weight: 600;
  margin-bottom: 1.25rem;
  white-space: pre-line;
}

.option {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  padding: 0.75rem 1rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  margin-bottom: 0.6rem;
  cursor: pointer;
  background: var(--color-card);
  transition: all 0.15s;
  font-size: 0.95rem;
}
.option:hover { border-color: var(--color-secondary); background: rgba(13, 71, 161, 0.04); }
.option .option-letter {
  font-weight: 700;
  width: 26px; height: 26px;
  border-radius: 999px;
  border: 2px solid var(--color-border);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 0.85rem;
  flex-shrink: 0;
}
.option.selected { border-color: var(--color-secondary); }
.option.selected .option-letter { background: var(--color-secondary); color: #fff; border-color: var(--color-secondary); }
.option.correct { border-color: var(--color-success); background: rgba(46, 125, 50, 0.08); }
.option.correct .option-letter { background: var(--color-success); color: #fff; border-color: var(--color-success); }
.option.incorrect { border-color: var(--color-danger); background: rgba(198, 40, 40, 0.08); }
.option.incorrect .option-letter { background: var(--color-danger); color: #fff; border-color: var(--color-danger); }
.option.disabled { cursor: default; opacity: 0.85; }
.option.disabled:hover { border-color: var(--color-border); background: var(--color-card); }

.explanation {
  margin-top: 1rem;
  padding: 1rem;
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-left: 4px solid var(--color-success);
  border-radius: var(--radius-sm);
  display: none;
}
.explanation.show { display: block; }
.explanation h4 { margin-bottom: 0.4rem; font-size: 1rem; }

.answer-feedback { margin-top: 0.75rem; font-weight: 700; font-size: 1rem; }
.fb-correct { color: var(--color-success); }
.fb-incorrect { color: var(--color-danger); }

/* ---------- Grid question navigator ---------- */
.question-nav { display: flex; flex-wrap: wrap; gap: 0.4rem; margin: 1rem 0; }
.qnav-btn {
  width: 36px; height: 36px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-card);
  color: var(--color-text);
  font-weight: 700;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}
.qnav-btn.current { border-color: var(--color-secondary); box-shadow: 0 0 0 2px rgba(13,71,161,0.2); }
.qnav-btn.answered { background: rgba(46,125,50,0.15); color: var(--color-success); border-color: var(--color-success); }
.qnav-btn.flagged { background: rgba(255,111,0,0.15); color: var(--color-accent); border-color: var(--color-accent); }

/* ---------- Results / summary ---------- */
.result-card { text-align: center; }
.result-score { font-size: 3rem; font-weight: 800; color: var(--color-primary); font-family: var(--font-heading); }
.result-subtitle { color: var(--color-muted); margin-bottom: 1rem; }
.result-verdict { font-size: 1.1rem; font-weight: 700; margin: 0.5rem 0; }

/* ---------- Simulator ---------- */
.sim-setup { max-width: 780px; margin: 0 auto; }
.section-order-list { display: flex; flex-direction: column; gap: 0.5rem; }
.section-order-item {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.75rem 1rem;
  background: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  cursor: grab;
}
.section-order-item .drag-handle { cursor: grab; color: var(--color-muted); }
.section-order-item.dragging { opacity: 0.5; }
.calc {
  position: fixed;
  bottom: 1rem;
  right: 1rem;
  width: 260px;
  background: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-card-hover);
  padding: 0.75rem;
  z-index: 200;
  display: none;
}
.calc.open { display: block; }
.calc-display {
  width: 100%;
  padding: 0.6rem;
  text-align: right;
  font-size: 1.3rem;
  font-family: var(--font-heading);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-bg);
  margin-bottom: 0.5rem;
  color: var(--color-text);
}
.calc-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 0.35rem; }
.calc-btn {
  padding: 0.6rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-bg);
  font-weight: 700;
  font-size: 0.95rem;
  color: var(--color-text);
}
.calc-btn.op { background: rgba(255,111,0,0.15); color: var(--color-accent); }
.calc-btn-eq { grid-column: span 2; background: var(--color-secondary); color: #fff; }

/* ---------- Analytics ---------- */
.chart-box {
  background: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1.25rem;
  margin-bottom: 1.25rem;
}
.chart-box canvas { max-height: 320px; }
.chart-title { font-weight: 700; margin-bottom: 0.75rem; font-size: 1rem; }

.filter-row { display: flex; gap: 0.75rem; flex-wrap: wrap; align-items: center; margin-bottom: 1rem; }
.filter-row select { padding: 0.5rem 0.7rem; border: 1px solid var(--color-border); border-radius: var(--radius-sm); background: var(--color-card); color: var(--color-text); }

/* Heat map */
.heatmap { display: grid; grid-template-columns: repeat(auto-fill, minmax(140px, 1fr)); gap: 0.5rem; }
.heat-cell {
  padding: 0.6rem;
  border-radius: var(--radius-sm);
  text-align: center;
  font-size: 0.78rem;
}
.heat-cell .heat-val { font-weight: 800; font-size: 1rem; }

/* ---------- Progress / gamification ---------- */
.level-banner {
  text-align: center;
  padding: 2rem;
  border-radius: var(--radius);
  background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
  color: #fff;
  margin-bottom: 1.25rem;
}
.level-banner h2 { color: #fff; font-size: 1.8rem; }
.level-banner .level-name { font-size: 1.3rem; margin-bottom: 0.5rem; }
.level-banner .progress { background: rgba(255,255,255,0.3); }
.level-banner .progress-bar { background: var(--color-accent); }

.badge-grid { display: flex; flex-wrap: wrap; gap: 0.75rem; }
.badge-tile {
  flex: 1 1 140px;
  text-align: center;
  padding: 1rem;
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
}
.badge-tile.locked { opacity: 0.45; filter: grayscale(1); }
.badge-icon { font-size: 2rem; display: block; margin-bottom: 0.35rem; }
.badge-name { font-weight: 700; font-size: 0.85rem; }
.badge-desc { font-size: 0.75rem; color: var(--color-muted); }

/* ---------- Flashcards ---------- */
.flashcard {
  perspective: 1000px;
  height: 320px;
  cursor: pointer;
  margin: 0 auto;
  max-width: 640px;
}
.flashcard-inner {
  position: relative;
  width: 100%;
  height: 100%;
  transition: transform 0.6s;
  transform-style: preserve-3d;
}
.flashcard.flipped .flashcard-inner { transform: rotateY(180deg); }
.flashcard-face {
  position: absolute;
  inset: 0;
  backface-visibility: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 2rem;
  border-radius: var(--radius);
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-card-hover);
  background: var(--color-card);
  font-size: 1.1rem;
  font-weight: 600;
}
.flashcard-back { transform: rotateY(180deg); }

/* ---------- Toast ---------- */
.toast-container {
  position: fixed;
  bottom: 1rem;
  left: 50%;
  transform: translateX(-50%);
  z-index: 300;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  pointer-events: none;
}
.toast {
  background: var(--color-text);
  color: var(--color-bg);
  padding: 0.75rem 1.25rem;
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-card-hover);
  font-size: 0.9rem;
  font-weight: 600;
  animation: slideUp 0.3s ease;
  pointer-events: auto;
  max-width: 90vw;
}
.toast.success { background: var(--color-success); color: #fff; }
.toast.error { background: var(--color-danger); color: #fff; }
.toast.warning { background: var(--color-accent); color: #fff; }
@keyframes slideUp { from { opacity: 0; transform: translateY(20px); } to { opacity: 1; transform: translateY(0); } }

/* ---------- Modal ---------- */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.5);
  z-index: 250;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1rem;
  animation: fadeIn 0.2s ease;
}
@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }
.modal {
  background: var(--color-card);
  border-radius: var(--radius);
  max-width: 560px;
  width: 100%;
  max-height: 85vh;
  overflow-y: auto;
  padding: 1.5rem;
  box-shadow: var(--shadow-card-hover);
}
.modal-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 1rem; }
.modal-close { background: none; border: none; font-size: 1.4rem; color: var(--color-muted); }

/* ---------- Loading ---------- */
.loading-screen { text-align: center; padding: 4rem 1rem; color: var(--color-muted); }
.spinner {
  width: 40px; height: 40px;
  border: 4px solid var(--color-border);
  border-top-color: var(--color-accent);
  border-radius: 50%;
  margin: 0 auto 1rem;
  animation: spin 0.8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* ---------- Empty state ---------- */
.empty-state { text-align: center; padding: 3rem 1rem; color: var(--color-muted); }
.empty-state .empty-icon { font-size: 3rem; display: block; margin-bottom: 0.75rem; }

/* ---------- Tabs within views ---------- */
.tabs { display: flex; gap: 0.35rem; border-bottom: 2px solid var(--color-border); margin-bottom: 1.25rem; flex-wrap: wrap; }
.tab-btn {
  padding: 0.6rem 1rem;
  border: none;
  background: none;
  color: var(--color-muted);
  font-weight: 700;
  border-bottom: 3px solid transparent;
  margin-bottom: -2px;
}
.tab-btn.active { color: var(--color-primary); border-bottom-color: var(--color-primary); }

/* ---------- Calendar planner ---------- */
.planner-grid { display: grid; grid-template-columns: repeat(7, 1fr); gap: 0.5rem; }
.planner-day {
  padding: 0.6rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  min-height: 90px;
  font-size: 0.8rem;
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
}
.planner-day .day-label { font-weight: 700; }
.planner-slots { display: flex; flex-direction: column; gap: 0.2rem; }
.planner-slot {
  background: rgba(13,71,161,0.1);
  border: none;
  border-radius: 4px;
  padding: 0.2rem 0.35rem;
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--color-secondary);
  text-align: left;
  cursor: pointer;
}

/* ---------- Misc utilities ---------- */
.row { display: flex; gap: 0.75rem; align-items: center; }
.row-wrap { flex-wrap: wrap; }
.col { display: flex; flex-direction: column; gap: 0.75rem; }
.gap-sm { gap: 0.5rem; }
.gap-lg { gap: 2rem; }
.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }
.text-center { text-align: center; }
.text-muted { color: var(--color-muted); }
.text-accent { color: var(--color-accent); }
.text-success { color: var(--color-success); }
.text-danger { color: var(--color-danger); }
.fs-small { font-size: 0.85rem; }
.fs-large { font-size: 1.25rem; }
.fw-bold { font-weight: 700; }
.flag-btn { background: none; border: 1px solid var(--color-border); border-radius: var(--radius-sm); padding: 0.4rem 0.7rem; font-size: 0.85rem; color: var(--color-muted); }
.flag-btn.active { background: rgba(255,111,0,0.15); color: var(--color-accent); border-color: var(--color-accent); }
.flagged-active { background: rgba(255,111,0,0.18); color: var(--color-accent); border-color: var(--color-accent); }
.gauge-cell { display: flex; align-items: center; gap: 0.75rem; }
.gauge-ring { width: 14px; height: 14px; border-radius: 50%; flex-shrink: 0; }

/* ---------- View-specific utilities ---------- */
.section-title {
  font-size: 1.1rem;
  font-weight: 700;
  margin: 1.5rem 0 0.75rem;
}
.stat-value { font-size: 1.9rem; font-weight: 800; line-height: 1.1; }
.stat-label { font-size: 0.82rem; color: var(--color-muted); font-weight: 600; }
.stat-inline { text-align: center; }
.stat-display { font-weight: 800; line-height: 1; }
.field-row { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 1rem; }
.card-muted { opacity: 0.7; }
.table-scroll { overflow-x: auto; }
.clue-box {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-left: 4px solid var(--color-secondary);
  padding: 1rem;
  border-radius: var(--radius-sm);
}
.flash-card { user-select: none; }
.badge-error { background: rgba(198, 40, 40, 0.15); color: var(--color-danger); }
.badge-secondary { background: rgba(13, 71, 161, 0.12); color: var(--color-secondary); }
.badge-ghost { background: var(--color-border); color: var(--color-text); }
.progress-bar.success { background: var(--color-success); }

/* ---------- Data Insights format widgets ---------- */
.di-graphics svg { display: block; margin: 0 auto; }
.di-graphics svg text { font-family: inherit; }
.di-msr-tabs { margin-bottom: .25rem; }
.di-answer .di-col-label { font-weight: 700; margin-bottom: .3rem; font-size: .92rem; }
.di-select {
  width: 100%;
  max-width: 360px;
  padding: .5rem .6rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-card);
  color: var(--color-text);
  font: inherit;
}
.di-table-wrap { border: 1px solid var(--color-border); border-radius: var(--radius-sm); background: var(--color-card); }
table.di-table {
  width: 100%;
  border-collapse: collapse;
  font-size: .92rem;
}
.di-table th, .di-table td {
  border-bottom: 1px solid var(--color-border);
  padding: .45rem .6rem;
  text-align: left;
  white-space: nowrap;
}
.di-table th { font-weight: 700; background: var(--color-bg); }
.di-table tbody tr:last-child td { border-bottom: none; }
.di-yesno { display: inline-flex; align-items: center; gap: .25rem; margin-right: .8rem; font-size: .9rem; cursor: pointer; }
.di-yesno input { accent-color: var(--color-primary); }

/* ---------- Responsive ---------- */
@media (max-width: 900px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  .hamburger { display: flex; }
  .main-nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    flex-direction: column;
    background: var(--color-card);
    border-bottom: 1px solid var(--color-border);
    box-shadow: var(--shadow-card-hover);
    padding: 0.5rem 1rem;
    margin-left: 0;
  }
  .main-nav.open { display: flex; }
  .header-stats { display: none; }
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .planner-grid { grid-template-columns: repeat(1, 1fr); }
  .brand-text { font-size: 0.95rem; }
}

@media (max-width: 480px) {
  .header-inner { padding: 0.6rem 0.9rem; gap: 0.5rem; }
  .app-view { padding: 1rem 0.9rem 4rem; }
  .brand-mark { font-size: 1.1rem; }
}

/* =====================================================================
   Lessons v1.1 — study-optimized layout, structure & typography
   All new rules are additive; shared classes (example-*, lesson-box-*,
   formula-table) used by practice/simulator/analytics are tuned only
   under the .lesson-container scope.
   ===================================================================== */
:root { --font-reading: 'Source Serif 4', Georgia, 'Times New Roman', serif; }
[data-theme="dark"] { --font-reading: 'Source Serif 4', Georgia, 'Times New Roman', serif; }

/* Reading progress bar pinned to the very top of the viewport */
.lesson-progress-fixed {
  position: fixed;
  top: 0;
  left: 0;
  height: 4px;
  width: 0%;
  background: linear-gradient(90deg, var(--color-primary), var(--color-accent));
  z-index: 400;
  border-radius: 0 2px 2px 0;
  transition: width 90ms linear;
  pointer-events: none;
}

.lesson-header h1 {
  font-size: 2rem;
  font-weight: 800;
  margin: 1.1rem 0 0.45rem;
  letter-spacing: -0.01em;
}
.lesson-meta { display: flex; flex-wrap: wrap; gap: 0.55rem; align-items: center; font-size: 0.9rem; }

/* Outline / table of contents */
.lesson-toc {
  background: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1rem 1.2rem;
  margin: 1.3rem 0 2.2rem;
  box-shadow: var(--shadow-card);
}
.lesson-toc-title {
  font-weight: 800;
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.07em;
  color: var(--color-muted);
  margin-bottom: 0.7rem;
}
.lesson-toc-list { display: flex; flex-wrap: wrap; gap: 0.5rem; }
.lesson-toc-link {
  font-size: 0.84rem;
  font-weight: 600;
  padding: 0.4rem 0.85rem;
  border: 1px solid var(--color-border);
  border-radius: 999px;
  background: var(--color-bg);
  color: var(--color-text);
  transition: all 0.15s;
  cursor: pointer;
}
.lesson-toc-link:hover { border-color: var(--color-secondary); color: var(--color-secondary); }
.lesson-toc-link.active { background: var(--color-primary); border-color: var(--color-primary); color: var(--color-bg); }

[id^="lesson-"] { scroll-margin-top: 88px; }

/* Section scaffolding */
.lesson-section { margin-bottom: 2.6rem; }
.lesson-section > h3 {
  font-size: 1.28rem;
  font-weight: 800;
  margin-bottom: 1rem;
  padding-bottom: 0.55rem;
  border-bottom: 2px solid var(--color-border);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}
.lesson-section > h3 .text-muted { font-size: 0.95rem; font-weight: 600; }

/* Overview reading column: larger serif type, drop cap for focus */
.lesson-overview p {
  font-size: 1.13rem;
  line-height: 1.78;
  margin: 0 0 1.15rem;
  color: var(--color-text);
}
.lesson-overview p.lesson-lead { font-size: 1.2rem; }
.lesson-overview > p:first-of-type::first-letter {
  font-family: var(--font-reading);
  font-weight: 700;
  font-size: 3.1em;
  line-height: 0.85;
  float: left;
  padding: 0.05em 0.1em 0 0;
  color: var(--color-primary);
}
.lesson-insight {
  display: flex;
  gap: 0.75rem;
  align-items: flex-start;
  background: linear-gradient(135deg, rgba(13, 71, 161, 0.06), rgba(255, 111, 0, 0.05));
  border: 1px solid rgba(13, 71, 161, 0.22);
  border-left: 4px solid var(--color-secondary);
  border-radius: var(--radius-sm);
  padding: 1rem 1.15rem;
  margin: 1.35rem 0;
}
.lesson-insight p { margin: 0; font-size: 1rem; line-height: 1.65; color: var(--color-text); }
.lesson-insight b { color: var(--color-secondary); }

/* Formulas as scannable cards (replaces the dense table) */
.formula-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(270px, 1fr)); gap: 0.9rem; margin: 1rem 0; }
.formula-card {
  background: var(--color-card);
  border: 1px solid var(--color-border);
  border-top: 3px solid var(--color-secondary);
  border-radius: var(--radius-sm);
  padding: 1rem 1.05rem;
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
  box-shadow: var(--shadow-card);
}
.formula-card .formula-term { font-weight: 700; font-size: 0.93rem; color: var(--color-primary); letter-spacing: 0.01em; }
.formula-card .formula-def { font-family: var(--font-reading); font-size: 0.98rem; line-height: 1.6; color: var(--color-text); }

/* Numbered strategy / trap steps */
.lesson-step { display: flex; gap: 0.8rem; align-items: flex-start; margin: 0.7rem 0; }
.lesson-step-num {
  flex-shrink: 0;
  width: 27px;
  height: 27px;
  border-radius: 999px;
  background: var(--color-secondary);
  color: #fff;
  font-weight: 800;
  font-size: 0.85rem;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  margin-top: 0.15rem;
}
.lesson-step-body { font-size: 1.02rem; line-height: 1.7; color: var(--color-text); }
.lesson-trap .lesson-step-num { background: var(--color-danger); }

/* Worked examples */
.example-head { display: flex; align-items: center; gap: 0.6rem; margin-bottom: 0.55rem; }
.example-pill {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: 999px;
  padding: 0.22rem 0.75rem;
  font-size: 0.7rem;
  font-weight: 800;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--color-secondary);
}
.lesson-container .example-question {
  font-family: var(--font-reading);
  font-size: 1.08rem;
  line-height: 1.7;
  font-weight: 500;
  white-space: pre-line;
  margin-bottom: 0.7rem;
}
.lesson-container .option { font-size: 0.98rem; }
.lesson-container .option.disabled { cursor: default; }
.lesson-container .option.disabled:hover { border-color: var(--color-border); background: var(--color-card); }
.option.correct-answer { border-color: var(--color-success); background: rgba(46, 125, 50, 0.09); }
.option.correct-answer .option-letter { background: var(--color-success); color: #fff; border-color: var(--color-success); }
.example-controls { margin-top: 0.45rem; }
.lesson-container .example-answer { color: var(--color-success); font-weight: 800; margin-top: 0.85rem; }
.lesson-container .example-reason {
  border-left: 3px solid var(--color-border);
  padding: 0.35rem 0 0.35rem 0.95rem;
  margin-top: 0.5rem;
  font-size: 0.98rem;
  line-height: 1.7;
  color: var(--color-text);
}

/* Quick check */
.quickcheck-progress { font-size: 0.8rem; font-weight: 700; color: var(--color-muted); white-space: nowrap; }

/* Practice CTA + prev/next course navigation */
.lesson-practice-cta {
  margin-top: 2.2rem;
  background: linear-gradient(135deg, rgba(13, 71, 161, 0.06), rgba(255, 111, 0, 0.04));
  border: 1px dashed var(--color-border);
  border-radius: var(--radius);
  padding: 1.15rem 1.3rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
}
.lesson-nav { display: flex; gap: 0.8rem; margin: 1.5rem 0 1rem; }
.lesson-nav-card {
  flex: 1;
  display: block;
  padding: 0.95rem 1.1rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  background: var(--color-card);
  transition: all 0.18s;
  text-decoration: none;
}
a.lesson-nav-card:hover { border-color: var(--color-secondary); box-shadow: var(--shadow-card-hover); transform: translateY(-1px); }
.lesson-nav-card.disabled { opacity: 0.5; pointer-events: none; }
.lesson-nav-label { font-size: 0.72rem; text-transform: uppercase; letter-spacing: 0.06em; font-weight: 800; color: var(--color-muted); }
.lesson-nav-title { font-weight: 700; color: var(--color-text); margin-top: 0.25rem; font-size: 0.95rem; line-height: 1.35; }

@media (max-width: 768px) {
  .formula-grid { grid-template-columns: 1fr; }
  .lesson-overview p { font-size: 1.06rem; line-height: 1.7; }
  .lesson-header h1 { font-size: 1.6rem; }
  .lesson-nav { flex-direction: column; }
}

/* =====================================================================
   v1.4.0 Study UX additions: phase banner, pacing, meta tags, hints,
   keyboard hints, focused modules.
   ===================================================================== */

/* Study-phase banner */
.study-phase-banner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 1rem;
  padding: 1rem 1.25rem;
  border: 1px solid var(--color-border);
  border-radius: 12px;
  background: linear-gradient(120deg, rgba(13,71,161,0.06), rgba(255,111,0,0.05));
  margin-bottom: 1.5rem;
}
.phase-badge {
  font-weight: 800;
  font-size: 0.95rem;
  padding: 0.35rem 0.8rem;
  border-radius: 999px;
  background: var(--color-primary);
  color: #fff;
  white-space: nowrap;
}
.phase-info { flex: 1; min-width: 220px; }
.phase-label { font-size: 0.7rem; text-transform: uppercase; letter-spacing: 0.08em; color: var(--color-muted); font-weight: 800; }
.phase-desc { font-size: 0.95rem; line-height: 1.4; }
.phase-progress-wrap {
  flex: 1; min-width: 160px; height: 8px; border-radius: 999px;
  background: var(--color-border); overflow: hidden;
}
.phase-progress-bar { height: 100%; background: linear-gradient(90deg, var(--color-primary), var(--color-accent)); border-radius: 999px; transition: width .4s ease; }
.phase-next { font-size: 0.8rem; color: var(--color-muted); max-width: 260px; }

/* Pace feedback rows/chips */
.pace-target-chip { line-height: 1.4; }
.pace-row {
  display: flex; align-items: center; gap: .75rem;
  padding: .4rem .6rem; border-radius: 8px; margin-bottom: .3rem;
  font-size: .88rem; background: var(--color-card);
}
.pace-sec { width: 70px; font-weight: 700; }
.pace-verdict { margin-left: auto; font-weight: 700; font-size: .8rem; }
.pace-fast { border-left: 3px solid var(--color-accent); }
.pace-fast .pace-verdict { color: var(--color-accent); }
.pace-slow { border-left: 3px solid var(--color-danger); }
.pace-slow .pace-verdict { color: var(--color-danger); }
.pace-ok { border-left: 3px solid var(--color-success); }
.pace-ok .pace-verdict { color: var(--color-success); }
.pace-line { margin: .5rem 0; font-size: .85rem; color: var(--color-muted); }

/* Post-answer meta tag rows */
.meta-tag-row {
  display: flex; flex-wrap: wrap; align-items: center; gap: .5rem;
  margin: .7rem 0; padding: .6rem 0; border-top: 1px dashed var(--color-border);
}
.meta-label { font-size: .78rem; font-weight: 800; text-transform: uppercase; letter-spacing: .05em; color: var(--color-muted); min-width: 96px; }
.meta-btn {
  border: 1px solid var(--color-border); background: var(--color-card);
  border-radius: 999px; padding: .35rem .8rem; font-size: .85rem; cursor: pointer;
  color: var(--color-text); transition: all .15s ease;
}
.meta-btn:hover { border-color: var(--color-secondary); }
.meta-btn.active { background: var(--color-secondary); color: #fff; border-color: var(--color-secondary); }
.mt-careless.active { background: #F9A825; border-color: #F9A825; color: #212121; }
.mt-conceptual.active { background: #3949AB; border-color: #3949AB; color: #fff; }
.mt-timing.active { background: #E53935; border-color: #E53935; color: #fff; }
.mt-misread.active { background: #7B1FA2; border-color: #7B1FA2; color: #fff; }

/* Note row */
.note-row { display: flex; flex-direction: column; gap: .5rem; margin: .7rem 0; }
.note-row textarea {
  width: 100%; resize: vertical; min-height: 52px;
  border: 1px solid var(--color-border); border-radius: 8px;
  padding: .6rem .75rem; font: inherit; font-size: .9rem; color: var(--color-text); background: var(--color-card);
}

/* Hint panel */
.hint-panel {
  margin: .8rem 0; padding: .8rem 1rem; border-radius: 10px;
  background: rgba(255, 193, 7, 0.12); border: 1px dashed var(--color-accent);
  display: flex; gap: .6rem; align-items: flex-start;
  animation: fadeIn .2s ease;
}
.hint-icon { font-size: 1.1rem; }
.hint-text { font-size: .95rem; line-height: 1.5; flex: 1; }
.verdict-row { font-size: 1.05rem; font-weight: 700; }
.explanation-body { margin-top: .5rem; line-height: 1.55; }
.practice-actions-row {
  display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: .5rem; margin-top: .9rem;
}
.kbd-hint { font-size: .75rem; color: var(--color-muted); }
.kbd-hint kbd {
  background: var(--color-card); border: 1px solid var(--color-border); border-bottom-width: 2px;
  border-radius: 4px; padding: 0 .35rem; font-family: ui-monospace, SFMono-Regular, Menlo, monospace; font-size: .72rem;
}

/* Feedback bottom action row */
.feedback-actions { gap: .5rem; flex-wrap: wrap; margin-top: .9rem; }
.feedback-actions .btn { margin: 0; }
.flagged-active { background: rgba(197, 48, 48, 0.15); }

/* Focused modules from dashboard */
.fs-large { font-size: 1.15rem; }
.mt-2 { margin-top: .5rem; }

@keyframes fadeIn { from { opacity: 0; transform: translateY(-3px); } to { opacity: 1; transform: none; } }

/* v1.4.0 touch targets + question readability */
.option, .opt { min-height: 44px; padding: .65rem .85rem; font-size: 1.02rem; }
.question-text { font-size: 1.12rem; line-height: 1.5; }
.passage-text, .clue-box { font-size: 1.02rem; }
.feedback-actions .btn, .mode-card .btn, .question-topbar .btn { min-height: 40px; }

/* v1.5.0 chapter tests (TTP-style difficulty ladder) */
.ct-banner {
  display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: .5rem;
  padding: .7rem 1rem; margin-bottom: 1rem; border-radius: 10px;
  background: linear-gradient(135deg, rgba(98,0,234,.14), rgba(0,121,107,.12));
  border: 1px solid var(--color-border);
}
.ct-banner-title { font-weight: 800; font-size: .98rem; }
.ct-banner-meta { font-size: .82rem; color: var(--color-muted); }
.ct-result { padding: .8rem 1rem; border-radius: 10px; margin: .5rem 0 0; font-size: .95rem; font-weight: 600; }
.ct-result.pass { background: rgba(0, 140, 60, .14); border: 1px solid rgba(0, 140, 60, .35); }
.ct-result.fail { background: rgba(197, 48, 48, .12); border: 1px solid rgba(197, 48, 48, .3); }
.ct-ladder-grid { margin-top: .75rem; }
.ct-card { padding: 1rem; display: flex; flex-direction: column; gap: .75rem; }
.ct-icon { font-size: 1.15rem; }
.ct-label { font-weight: 800; font-size: 1rem; text-transform: capitalize; }
.ct-note { min-height: 2.4em; line-height: 1.35; }
.course-road { display: flex; gap: .4rem; flex-wrap: wrap; align-items: stretch; }
.road-step {
  display: inline-flex; align-items: center; gap: .4rem; padding: .35rem .6rem; border-radius: 8px;
  border: 1px solid var(--color-border); background: var(--color-card);
  color: var(--color-text); text-decoration: none; font-size: .8rem; transition: transform .12s ease, border-color .12s ease;
}
.road-step:hover { transform: translateY(-1px); border-color: var(--color-secondary); }
.road-step.done { opacity: .65; }
.road-step.done .road-icon { color: #0a7d33; }
.road-step.doing { border-color: var(--color-accent); }
.road-step.next { border-color: var(--color-secondary); box-shadow: 0 0 0 2px rgba(71,85,105,.15); background: linear-gradient(135deg, rgba(98,0,234,.12), rgba(255,193,7,.10)); }
.road-num {
  min-width: 1.45em; height: 1.45em; display: inline-flex; align-items: center; justify-content: center;
  border-radius: 50%; background: var(--color-bg); border: 1px solid var(--color-border); font-size: .72rem; font-weight: 700;
}
.road-step.next .road-num { background: var(--color-secondary); color: #fff; border-color: var(--color-secondary); }
.road-name { font-weight: 600; }
.road-arrow { align-self: center; color: var(--color-muted); font-size: 1rem; padding: 0 .1rem; }
.road-step.road-lv-foundation { border-left: 3px solid rgba(46, 125, 50, .55); }
.road-step.road-lv-beginner { border-left: 3px solid rgba(46, 125, 50, .9); }
.road-step.road-lv-intermediate { border-left: 3px solid var(--color-accent); }
.road-step.road-lv-advanced { border-left: 3px solid var(--color-danger); }

.stage-chip {
  display: inline-flex; align-items: center; gap: .3rem; padding: .25rem .55rem; border-radius: 999px;
  font-size: .75rem; font-weight: 600; border: 1px solid var(--color-border); background: var(--color-card); color: var(--color-text);
}
.stage-chip-foundation { border-color: rgba(46, 125, 50, .4); }
.stage-chip-beginner { border-color: rgba(46, 125, 50, .7); }
.stage-chip-intermediate { border-color: rgba(255, 111, 0, .45); }
.stage-chip-advanced { border-color: rgba(198, 40, 40, .45); }

.topic-card.topic-level-foundation { border-left: 3px solid rgba(46, 125, 50, .35); }
.topic-card.topic-level-beginner { border-left: 3px solid rgba(46, 125, 50, .65); }
.topic-card.topic-level-intermediate { border-left: 3px solid var(--color-accent); }
.topic-card.topic-level-advanced { border-left: 3px solid var(--color-danger); }
.topic-card.topic-locked { opacity: .78; }
.topic-card.topic-locked:hover { opacity: 1; }
.topic-card .topic-meta { font-size: .78rem; color: var(--color-muted); margin-top: .2rem; text-transform: capitalize; }

/* v1.5.0 simulator: on-screen calculator + post-exam review */
.sim-calc-wrap { border: 1px solid var(--color-border); border-radius: 10px; padding: 1rem; background: var(--color-bg); }
.sim-calc { margin-top: .6rem; }
.sim-calc-display {
  background: var(--color-card); border: 1px solid var(--color-border); border-radius: 8px;
  font-size: 1.3rem; font-weight: 700; text-align: right; padding: .5rem .75rem; margin-bottom: .6rem;
  min-height: 3rem; overflow: hidden; white-space: nowrap;
}
.sim-calc-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: .45rem; }
.calc-key {
  min-height: 46px; border-radius: 8px; border: 1px solid var(--color-border);
  background: var(--color-card); color: var(--color-text); font-size: 1.05rem; font-weight: 600;
  cursor: pointer; transition: transform .08s ease, background .12s ease;
}
.calc-key:hover { transform: translateY(-1px); background: var(--color-bg); }
.calc-key:active { transform: translateY(0); background: var(--color-border); }
.calc-key.fn { background: rgba(197, 48, 48, .12); color: #c53030; }
.calc-key.op { background: rgba(98, 0, 234, .1); color: var(--color-primary); }
.calc-key.eq { background: var(--color-primary); color: #fff; border-color: var(--color-primary); }
.sim-review-grid { display: flex; flex-wrap: wrap; gap: .4rem; }
.sim-review-chip {
  width: 30px; height: 30px; border-radius: 50%; border: 1px solid var(--color-border);
  background: var(--color-card); color: var(--color-text); font-size: .78rem; font-weight: 700;
  cursor: pointer; transition: transform .08s ease;
}
.sim-review-chip:hover { transform: scale(1.15); }
.chip-ok { background: rgba(0, 140, 60, .18); color: #0a7d33; border-color: rgba(0, 140, 60, .5); }
.chip-bad { background: rgba(197, 48, 48, .18); color: #c53030; border-color: rgba(197, 48, 48, .5); }
.chip-un { background: var(--color-bg); color: var(--color-muted); }

/* ------------------- Advisor view (v1.10.0) ------------------- */
.advisor-wrap { display: flex; flex-direction: column; gap: 1.25rem; }
.advisor-kicker { font-size: .78rem; font-weight: 800; text-transform: uppercase; letter-spacing: .08em; color: var(--color-muted); }
.advisor-score { font-size: 3rem; font-weight: 800; line-height: 1; font-family: var(--font-heading); }
.advisor-big { font-size: 1.9rem; font-weight: 800; line-height: 1.1; font-family: var(--font-heading); }
.advisor-gap { font-size: .9rem; font-weight: 700; margin: .4rem 0; }
.advisor-scale-labels { display: flex; justify-content: space-between; font-size: .72rem; color: var(--color-muted); margin-top: .2rem; }
.advisor-read p { position: relative; padding-left: 1rem; border-left: 3px solid var(--color-border); margin: 0 0 .9rem; }
.advisor-read p:first-child { border-left-color: var(--color-primary); }
.advisor-directive { border: 2px solid var(--color-primary); }
.advisor-directive-main { font-size: 1.25rem; font-weight: 800; margin: .3rem 0 .4rem; }
.advisor-action { padding: .7rem .6rem; border-bottom: 1px dashed var(--color-border); }
.advisor-action:last-child { border-bottom: none; }
.advisor-action-head { font-weight: 700; margin-bottom: .2rem; }
.advisor-frow { display: grid; grid-template-columns: 150px 1fr 70px 110px; gap: .75rem; align-items: center; padding: .45rem .6rem; border-bottom: 1px dashed var(--color-border); font-size: .88rem; }
.advisor-fhead { font-weight: 800; text-transform: uppercase; letter-spacing: .05em; font-size: .72rem; color: var(--color-muted); border-bottom: 1px solid var(--color-border); }
.advisor-frow:last-child { border-bottom: none; }
.advisor-acc { display: flex; align-items: center; gap: .5rem; min-width: 0; }
.advisor-acc-num { width: 38px; text-align: right; font-weight: 700; }
.advisor-note { font-size: .75rem; color: var(--color-muted); }
.advisor-links a { margin-right: .5rem; }
.advisor-date-input { border: 1px solid var(--color-border); border-radius: 8px; background: var(--color-bg); padding: .4rem .5rem; color: var(--color-text); font-size: .85rem; }
.advisor-date-input:focus { outline: 2px solid var(--color-primary); outline-offset: 1px; }
@media (max-width: 680px) {
  .advisor-frow { grid-template-columns: 1fr 1fr; }
  .advisor-frow > span:nth-child(3), .advisor-frow > span:nth-child(4) { text-align: left !important; }
  .advisor-score { font-size: 2.4rem; }
}

/* ------------------- Question Bank view (v1.11.0) ------------------- */
.bank-strip { display: flex; flex-wrap: wrap; gap: .5rem; margin: 0 0 1.1rem; }
.bank-chip {
  border: 1px solid var(--color-border); background: var(--color-card);
  border-radius: 999px; padding: .35rem .85rem; font-size: .85rem; cursor: pointer;
  color: var(--color-muted); transition: all .15s ease;
}
.bank-chip:hover { border-color: var(--color-secondary); color: var(--color-text); }
.bank-chip.active { background: var(--color-secondary); color: #fff; border-color: var(--color-secondary); font-weight: 700; }
.bank-coverage { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 1rem; margin-bottom: 1.1rem; }
.bank-sec-head { display: flex; align-items: baseline; justify-content: space-between; gap: .5rem; margin-bottom: .5rem; flex-wrap: wrap; }
.bank-sec-name { font-weight: 800; }
.bank-sec-blueprint { font-size: .78rem; color: var(--color-muted); }
.bank-sec-sub { font-size: .8rem; margin: .4rem 0 .7rem; }
.bank-topics { display: flex; flex-wrap: wrap; gap: .4rem; }
.bank-topic-chip {
  display: flex; align-items: center; gap: .35rem; padding: .28rem .6rem;
  border: 1px solid var(--color-border); border-radius: 999px; font-size: .82rem;
  background: var(--color-card); cursor: pointer; color: var(--color-text);
}
.bank-topic-chip:hover { border-color: var(--color-secondary); }
.bank-topic-un { color: var(--color-accent); font-weight: 800; }
.bank-filters { display: grid; grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); gap: .6rem; align-items: end; }
.bank-filters-card { padding: 1rem; }
.bank-field { display: flex; flex-direction: column; gap: .25rem; }
.bank-field > label { font-size: .72rem; font-weight: 800; text-transform: uppercase; letter-spacing: .05em; color: var(--color-muted); }
.bank-field select, .bank-field input {
  padding: .5rem .65rem; border: 1px solid var(--color-border); border-radius: var(--radius-sm);
  background: var(--color-card); color: var(--color-text); font-size: .9rem;
}
.bank-search { grid-column: span 2; }
.bank-actions { display: flex; flex-wrap: wrap; gap: .5rem; align-items: center; margin: 1rem 0 .5rem; }
.bank-count { font-weight: 800; font-size: 1rem; margin-right: auto; }
.bank-list { border: 1px solid var(--color-border); border-radius: var(--radius); overflow: hidden; }
.bank-item { border-bottom: 1px dashed var(--color-border); }
.bank-item:last-child { border-bottom: none; }
.bank-row {
  display: grid;
  grid-template-columns: 26px 118px minmax(0, 1fr) 86px 56px 52px 132px 108px;
  gap: .5rem; align-items: center; padding: .45rem .6rem; cursor: pointer; font-size: .88rem;
}
.bank-row:hover { background: var(--color-bg); }
.bank-row-head {
  display: grid;
  grid-template-columns: 26px 118px minmax(0, 1fr) 86px 56px 52px 132px 108px;
  gap: .5rem; padding: .4rem .6rem; font-size: .7rem; font-weight: 800;
  text-transform: uppercase; letter-spacing: .05em; color: var(--color-muted);
  border-bottom: 1px solid var(--color-border); background: var(--color-card);
}
.bank-main { min-width: 0; }
.bank-sub { font-weight: 700; }
.bank-id { color: var(--color-muted); font-size: .74rem; }
.bank-carets { color: var(--color-muted); }
.bank-mini { display: inline-block; width: 44px; height: 5px; background: var(--color-border); border-radius: 3px; overflow: hidden; vertical-align: middle; }
.bank-mini-fill { display: block; height: 100%; background: var(--color-success); }
.bank-mini-fill.low { background: var(--color-accent); }
.bank-mine { display: flex; flex-direction: column; gap: .15rem; font-size: .8rem; }
.bank-pct { font-weight: 800; font-size: .85rem; }
.bank-dot { display: inline-block; width: 8px; height: 8px; border-radius: 50%; background: var(--color-muted); vertical-align: middle; }
.bank-dot.ok { background: var(--color-success); }
.bank-dot.miss { background: var(--color-danger); }
.bank-pill { font-size: .72rem; font-weight: 800; padding: .16rem .45rem; border-radius: 999px; white-space: nowrap; }
.bank-pill.ok { background: rgba(0, 140, 60, .14); color: #0a7d33; }
.bank-pill.miss { background: rgba(197, 48, 48, .14); color: #c53030; }
.bank-pill.due { background: rgba(249, 168, 37, .2); color: #995a00; }
.bank-pill.err { background: rgba(197, 48, 48, .22); color: #8d2323; }
.bank-pill.new { background: var(--color-border); color: var(--color-muted); }
.bank-expand { padding: .5rem .7rem .9rem 3rem; border-top: 1px solid var(--color-border); background: var(--color-bg); font-size: .92rem; }
.bank-opt { position: relative; padding: .28rem 0 .28rem 1.5rem; }
.bank-opt .option-letter { position: absolute; left: 0; top: .28rem; }
.bank-opt.option-answer { font-weight: 600; }
.bank-ans { margin-top: .6rem; font-weight: 700; }
.bank-note { color: var(--color-muted); font-style: italic; margin: .3rem 0 .6rem; }
.bank-detail-block { margin-top: .8rem; padding-top: .5rem; border-top: 1px dashed var(--color-border); }
.bank-hist-item { font-size: .84rem; padding: .15rem 0; }
.bank-hist-meta { font-size: .8rem; color: var(--color-muted); }
.bank-note-input {
  width: 100%; resize: vertical; min-height: 52px;
  border: 1px solid var(--color-border); border-radius: 8px;
  padding: .6rem .75rem; font: inherit; font-size: .9rem; color: var(--color-text); background: var(--color-card);
  margin-bottom: .5rem;
}
.bank-check { accent-color: var(--color-secondary); width: 16px; height: 16px; cursor: pointer; }
.bank-col-acts { display: flex; gap: .35rem; justify-content: flex-end; }
@media (max-width: 900px) {
  .bank-row, .bank-row-head { grid-template-columns: 26px 118px minmax(0, 1fr) 132px 108px; }
  .bank-col-d, .bank-col-f, .bank-col-t { display: none; }
}
@media (max-width: 640px) {
  .bank-row, .bank-row-head { grid-template-columns: 24px 64px minmax(0, 1fr) 108px; }
  .bank-col-mine { display: none; }
  .bank-expand { padding-left: .7rem; }
  .bank-filters { grid-template-columns: 1fr 1fr; }
  .bank-search { grid-column: span 2; }
}