:root[data-theme="daylight"] {
  --bg-canvas: #f8fafc; --bg-card: #ffffff; --border-color: #e2e8f0;
  --text-primary: #0f172a; --text-secondary: #475569; --text-muted: #94a3b8;
  --accent-blue: #2563eb; --accent-green: #16a34a; --accent-amber: #d97706; --accent-red: #dc2626;
  --header-bg: #ffffff; --badge-bg: #eff6ff; --badge-text: #1e40af;
}
:root[data-theme="midnight"] {
  --bg-canvas: #090d16; --bg-card: #131b2e; --border-color: #23314d;
  --text-primary: #f1f5f9; --text-secondary: #94a3b8; --text-muted: #64748b;
  --accent-blue: #3b82f6; --accent-green: #22c55e; --accent-amber: #f59e0b; --accent-red: #ef4444;
  --header-bg: #101726; --badge-bg: #1e293b; --badge-text: #93c5fd;
}
:root[data-theme="eyecare"] {
  --bg-canvas: #f4f8f3; --bg-card: #ffffff; --border-color: #dbe5d8;
  --text-primary: #192e1b; --text-secondary: #3b543e; --text-muted: #728a75;
  --accent-blue: #2d7a4d; --accent-green: #1f8a4c; --accent-amber: #b46b0a; --accent-red: #c23838;
  --header-bg: #eaf2e8; --badge-bg: #e2efe0; --badge-text: #1d5932;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", sans-serif;
  background-color: var(--bg-canvas);
  color: var(--text-primary);
  line-height: 1.6;
  transition: background-color 0.2s ease, color 0.2s ease;
  min-height: 100vh;
}

header {
  background-color: var(--header-bg);
  border-bottom: 1px solid var(--border-color);
  position: sticky;
  top: 0;
  z-index: 50;
  box-shadow: 0 1px 3px rgba(0,0,0,0.03);
}
.header-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 14px 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
}
.brand-title {
  font-size: 18px;
  font-weight: 800;
  display: flex;
  align-items: center;
  gap: 8px;
}
.brand-badge {
  font-size: 11px;
  padding: 2px 8px;
  border-radius: 4px;
  background: var(--badge-bg);
  color: var(--badge-text);
  font-weight: 700;
}
.header-right {
  display: flex;
  align-items: center;
  gap: 12px;
}
.countdown-box {
  font-family: "SF Mono", Menlo, monospace;
  font-size: 13px;
  background: var(--bg-canvas);
  padding: 6px 12px;
  border-radius: 6px;
  border: 1px solid var(--border-color);
  color: var(--accent-blue);
  font-weight: 700;
}
.theme-switch {
  display: flex;
  background: var(--bg-canvas);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  overflow: hidden;
}
.theme-btn {
  border: none;
  background: transparent;
  padding: 5px 10px;
  font-size: 12px;
  cursor: pointer;
  color: var(--text-secondary);
  font-weight: 600;
}
.theme-btn.active {
  background: var(--accent-blue);
  color: #ffffff;
}

.main-container {
  max-width: 1200px;
  margin: 20px auto;
  padding: 0 20px 60px 20px;
}

.tab-bar {
  display: flex;
  gap: 6px;
  border-bottom: 2px solid var(--border-color);
  margin-bottom: 20px;
  overflow-x: auto;
  white-space: nowrap;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;
  padding-bottom: 6px;
}
.tab-bar::-webkit-scrollbar { display: none; }
.tab-item {
  padding: 7px 14px;
  border-radius: 8px;
  font-size: 13.5px;
  font-weight: 700;
  cursor: pointer;
  color: var(--text-secondary);
  border: 1px solid transparent;
  background: var(--bg-canvas);
  white-space: nowrap;
  transition: all 0.15s ease;
  flex-shrink: 0;
}
.tab-item:hover {
  color: var(--accent-blue);
  background: var(--bg-card);
}
.tab-item.active {
  color: var(--accent-blue);
  background: var(--bg-card);
  border-color: var(--border-color);
  box-shadow: 0 1px 3px rgba(0,0,0,0.06);
}

.tab-pane { display: none; }
.tab-pane.active { display: block; }

/* Bento Grid Cards */
.bento-grid-2x2 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 20px;
  margin-bottom: 24px;
}
.card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 20px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.02);
}
.card-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 14px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--border-color);
}
.card-title {
  font-size: 16px;
  font-weight: 700;
  color: var(--text-primary);
}
.card-tag {
  font-size: 11px;
  padding: 2px 8px;
  border-radius: 4px;
  font-weight: 600;
}

/* Form & Inputs */
.form-group {
  margin-bottom: 14px;
}
.form-label {
  display: block;
  font-size: 13px;
  font-weight: 600;
  margin-bottom: 6px;
  color: var(--text-secondary);
}
.form-control {
  width: 100%;
  padding: 8px 12px;
  border: 1px solid var(--border-color);
  border-radius: 6px;
  background: var(--bg-canvas);
  color: var(--text-primary);
  font-size: 14px;
}
.form-control:focus {
  outline: none;
  border-color: var(--accent-blue);
}
.checkbox-row {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px;
  border-radius: 8px;
  background: var(--bg-canvas);
  margin-bottom: 10px;
  cursor: pointer;
}
.checkbox-row input {
  width: 18px;
  height: 18px;
  cursor: pointer;
}
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 20px;
  border-radius: 6px;
  font-size: 14px;
  font-weight: 700;
  cursor: pointer;
  border: none;
  transition: background 0.15s ease;
}
.btn-primary {
  background: var(--accent-blue);
  color: #ffffff;
}
.btn-primary:hover {
  filter: brightness(1.1);
}
.btn-outline {
  background: transparent;
  border: 1px solid var(--border-color);
  color: var(--text-primary);
}

/* Storyboard Card Grid */
.story-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 16px;
}
.story-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 10px;
  padding: 16px;
  position: relative;
}
.story-id {
  position: absolute;
  top: 14px;
  right: 14px;
  font-family: monospace;
  font-size: 11px;
  background: var(--badge-bg);
  color: var(--badge-text);
  padding: 2px 6px;
  border-radius: 4px;
  font-weight: 700;
}

/* Table */
.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 13px;
}
.data-table th, .data-table td {
  padding: 10px 12px;
  text-align: left;
  border-bottom: 1px solid var(--border-color);
}
.data-table th {
  background: var(--bg-canvas);
  color: var(--text-secondary);
  font-weight: 700;
}

/* Timer Widget */
.timer-display {
  font-family: "SF Mono", monospace;
  font-size: 32px;
  font-weight: 800;
  color: var(--accent-red);
  text-align: center;
  margin: 12px 0;
}

/* RL Adaptive Mission Card */
.rl-mission-hero {
  background: linear-gradient(135deg, rgba(37, 99, 235, 0.08), rgba(16, 185, 129, 0.08));
  border: 1.5px solid var(--accent-blue);
  border-radius: 12px;
  padding: 22px;
}
.rl-mission-title {
  font-size: 18px;
  font-weight: 800;
  color: var(--text-primary);
  margin-bottom: 8px;
  display: flex;
  align-items: center;
  gap: 10px;
}
.rl-meta-bar {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  margin: 12px 0 16px 0;
}
.rl-stat-chip {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  padding: 6px 12px;
  border-radius: 6px;
  font-size: 13px;
  font-weight: 600;
}

/* Interactive Gyms */
.drill-section {
  margin-bottom: 24px;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--border-color);
}
.passage-box {
  background: var(--bg-canvas);
  border: 1px solid var(--border-color);
  padding: 16px;
  border-radius: 8px;
  font-size: 14px;
  line-height: 1.75;
  color: var(--text-primary);
  margin-bottom: 16px;
  max-height: 240px;
  overflow-y: auto;
}
.question-item {
  background: var(--bg-canvas);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 14px;
  margin-bottom: 12px;
}
.blank-input {
  border: 1.5px dashed var(--accent-blue);
  background: var(--bg-card);
  color: var(--text-primary);
  padding: 5px 10px;
  border-radius: 5px;
  font-size: 14px;
  font-weight: 600;
  width: 160px;
}
.synonym-pill {
  display: inline-block;
  background: #dcfce7;
  color: #15803d;
  border: 1px solid #86efac;
  border-radius: 4px;
  padding: 3px 8px;
  font-size: 12px;
  font-weight: 700;
  margin-top: 6px;
}
:root[data-theme="midnight"] .synonym-pill {
  background: #14532d;
  color: #86efac;
  border-color: #22c55e;
}
.explanation-box {
  background: var(--bg-card);
  border-left: 3px solid var(--accent-blue);
  padding: 8px 12px;
  margin-top: 8px;
  font-size: 12.5px;
  color: var(--text-secondary);
}

/* Vocab Flashcard */
.vocab-card {
  text-align: center;
  padding: 20px;
}
.vocab-word-large {
  font-size: 32px;
  font-weight: 900;
  color: var(--accent-blue);
  letter-spacing: 1px;
  margin-bottom: 18px;
}
.vocab-options-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  max-width: 600px;
  margin: 0 auto;
}
.vocab-opt-btn {
  background: var(--bg-canvas);
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  padding: 12px 16px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.15s ease;
  text-align: left;
}
.vocab-opt-btn:hover {
  border-color: var(--accent-blue);
  background: var(--bg-card);
}
.vocab-opt-btn.correct {
  background: #dcfce7 !important;
  color: #15803d !important;
  border-color: #22c55e !important;
}
.vocab-opt-btn.wrong {
  background: #fee2e2 !important;
  color: #991b1b !important;
  border-color: #ef4444 !important;
}

/* Writing Assessment UI */
.writing-textarea {
  width: 100%;
  min-height: 180px;
  padding: 14px;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  background: var(--bg-canvas);
  color: var(--text-primary);
  font-size: 14px;
  line-height: 1.6;
  font-family: inherit;
  resize: vertical;
}
.writing-rubric-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 12px; margin-top: 16px; }
.rubric-chip { background: var(--bg-canvas); border: 1px solid var(--border-color); border-radius: 8px; padding: 10px; text-align: center; }
.rubric-score { font-size: 20px; font-weight: 800; color: var(--accent-blue); }

/* Auth & Modal Privacy Shield (Rule LVII / ADR-0521) */
body.modal-open .main-container {
  filter: blur(24px) grayscale(30%);
  opacity: 0.15;
  pointer-events: none;
  user-select: none;
  transition: filter 0.3s ease, opacity 0.3s ease;
}
.auth-badge-btn {
  background: var(--bg-canvas); border: 1px solid var(--border-color); color: var(--text-secondary);
  padding: 5px 10px; font-size: 12px; font-weight: 700; border-radius: 6px; cursor: pointer; transition: all 0.15s ease;
}
.auth-badge-btn.master { background: #dcfce7; color: #15803d; border-color: #86efac; }
.table-responsive { width: 100%; overflow-x: auto; -webkit-overflow-scrolling: touch; }
.modal-overlay {
  position: fixed; inset: 0;
  background: rgba(10, 15, 29, 0.86);
  backdrop-filter: blur(32px) saturate(180%);
  -webkit-backdrop-filter: blur(32px) saturate(180%);
  z-index: 999;
  display: flex; align-items: center; justify-content: center; padding: 16px;
}
.modal-card {
  background: var(--bg-card); border: 1px solid var(--border-color); border-radius: 14px; padding: 22px;
  width: 100%; max-width: 440px; box-shadow: 0 20px 50px rgba(0,0,0,0.35); position: relative; z-index: 1001;
}
.modal-close-btn { border: none; background: transparent; font-size: 16px; cursor: pointer; color: var(--text-muted); }

@media (max-width: 768px) {
  .header-inner { flex-direction: column; align-items: stretch; gap: 8px; }
  .header-right { display: flex; justify-content: space-between; align-items: center; width: 100%; gap: 6px; }
  .countdown-box { font-size: 11px; padding: 4px 6px; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; max-width: 170px; }
  .bento-grid-2x2, .vocab-options-grid { grid-template-columns: 1fr; }
  .writing-rubric-grid { grid-template-columns: 1fr 1fr; }
  .btn { min-height: 42px; }
}