/* ===== FLTRP Junior English — Editorial Professional UI ===== */

.grammar-page {
  --navy: #0f1c2e;
  --navy-mid: #1a3050;
  --ink: #152033;
  --accent: #0a6e6a;
  --accent-hover: #085854;
  --accent-soft: rgba(10, 110, 106, 0.1);
  --gold: #a67c1a;
  --gold-soft: rgba(166, 124, 26, 0.14);
  --bg: #e8edf3;
  --bg-wash: #f3f6fa;
  --surface: #ffffff;
  --border: #cfd7e2;
  --border-soft: #e4e9f0;
  --text: #152033;
  --text-muted: #5a6a7c;
  --green: #0d6b4c;
  --orange: #b45f08;
  --purple: #5b2d8e;
  --teal: #0a6e6a;
  --radius: 12px;
  --radius-sm: 8px;
  --shadow: 0 1px 2px rgba(15, 28, 46, 0.04), 0 8px 24px rgba(15, 28, 46, 0.06);
  --shadow-lg: 0 16px 48px rgba(15, 28, 46, 0.12);
  --font-ui: 'IBM Plex Sans', 'Segoe UI', sans-serif;
  --font-display: 'Literata', Georgia, 'Times New Roman', serif;
  font-family: var(--font-ui);
  color: var(--text);
  background:
    radial-gradient(ellipse 80% 50% at 50% -10%, rgba(10, 110, 106, 0.07), transparent 55%),
    linear-gradient(180deg, var(--bg-wash) 0%, var(--bg) 40%, #e2e8f0 100%);
  line-height: 1.65;
  min-height: 100vh;
  box-sizing: border-box;
  isolation: isolate;
}

/* Isolate from dark site chrome */
body:has(.grammar-page) {
  background: var(--bg) !important;
}

body:has(.grammar-page) .footer-base {
  background: var(--navy) !important;
  border-top: none;
}

/* ---------- Hero ---------- */
.grammar-hero {
  background:
    linear-gradient(145deg, var(--navy) 0%, var(--navy-mid) 42%, #234866 100%);
  color: #fff;
  padding: 52px 40px 48px;
  position: relative;
  overflow: hidden;
}

.grammar-hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 50% 80% at 92% 10%, rgba(166, 124, 26, 0.18), transparent 50%),
    radial-gradient(ellipse 40% 60% at 8% 90%, rgba(10, 110, 106, 0.22), transparent 55%),
    url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23ffffff' fill-opacity='0.03'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
  pointer-events: none;
}

.grammar-hero::after {
  content: '';
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--gold) 0%, var(--accent) 50%, var(--gold) 100%);
}

.grammar-hero-inner {
  max-width: 1120px;
  margin: 0 auto;
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 40px;
  flex-wrap: wrap;
  position: relative;
  z-index: 1;
}

.grammar-hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: #f0d78c;
  background: var(--gold-soft);
  border: 1px solid rgba(240, 215, 140, 0.25);
  padding: 5px 14px;
  border-radius: 999px;
  margin-bottom: 16px;
}

.grammar-hero-badge::before {
  content: '';
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--gold);
  box-shadow: 0 0 0 3px rgba(166, 124, 26, 0.25);
  animation: pulseDot 2.4s ease-in-out infinite;
}

@keyframes pulseDot {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.7; transform: scale(0.85); }
}

.grammar-hero-text h1 {
  font-family: var(--font-display);
  font-size: clamp(1.75rem, 3.5vw, 2.35rem);
  font-weight: 700;
  margin: 0 0 12px;
  line-height: 1.2;
  letter-spacing: -0.025em;
  max-width: 16em;
}

.grammar-hero-text p {
  margin: 0;
  font-size: 0.98rem;
  color: rgba(255, 255, 255, 0.72);
  line-height: 1.7;
  max-width: 34em;
  font-weight: 400;
}

.grammar-hero-stats {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

.hero-stat {
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-sm);
  padding: 16px 18px 14px;
  text-align: center;
  min-width: 84px;
  backdrop-filter: blur(12px);
  transition: background 0.25s, transform 0.25s, border-color 0.25s;
  animation: fadeUp 0.55s ease both;
}

.hero-stat:nth-child(1) { animation-delay: 0.05s; }
.hero-stat:nth-child(2) { animation-delay: 0.1s; }
.hero-stat:nth-child(3) { animation-delay: 0.15s; }
.hero-stat:nth-child(4) { animation-delay: 0.2s; }
.hero-stat:nth-child(5) { animation-delay: 0.25s; }

.hero-stat:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: rgba(240, 215, 140, 0.35);
  transform: translateY(-2px);
}

@keyframes fadeUp {
  from { opacity: 0; transform: translateY(12px); }
  to { opacity: 1; transform: translateY(0); }
}

.hero-stat-num {
  display: block;
  font-family: var(--font-display);
  font-size: 1.65rem;
  font-weight: 700;
  color: #f0d78c;
  line-height: 1;
  letter-spacing: -0.02em;
}

.hero-stat-label {
  display: block;
  font-size: 0.7rem;
  color: rgba(255, 255, 255, 0.58);
  margin-top: 8px;
  letter-spacing: 0.02em;
}

/* Mobile toggle */
.grammar-mobile-toggle {
  display: none;
  align-items: center;
  gap: 8px;
  margin: 0;
  padding: 12px 20px;
  width: 100%;
  border: none;
  border-bottom: 1px solid var(--border);
  background: var(--surface);
  color: var(--navy);
  font-family: inherit;
  font-size: 0.88rem;
  font-weight: 600;
  cursor: pointer;
  box-sizing: border-box;
}

.grammar-mobile-toggle svg { width: 18px; height: 18px; }
.grammar-sidebar-backdrop { display: none; }

/* ---------- Layout ---------- */
.grammar-container {
  display: flex;
  align-items: flex-start;
  max-width: 1120px;
  margin: 0 auto;
  padding: 24px 20px 64px;
  gap: 20px;
  min-height: calc(100vh - 220px);
  position: relative;
  z-index: 2;
}

.grammar-sidebar {
  width: 248px;
  min-width: 248px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px 0 12px;
  position: sticky;
  top: 16px;
  max-height: calc(100vh - 32px);
  overflow-y: auto;
  box-sizing: border-box;
  box-shadow: var(--shadow);
  scrollbar-width: thin;
  scrollbar-color: var(--border) transparent;
}

.grammar-sidebar-header {
  padding: 0 16px 14px;
  border-bottom: 1px solid var(--border-soft);
  margin-bottom: 6px;
}

.grammar-sidebar-header h2 {
  font-size: 0.72rem;
  font-weight: 700;
  color: var(--navy);
  margin: 0 0 2px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.grammar-sidebar-header p {
  font-size: 0.75rem;
  color: var(--text-muted);
  margin: 0 0 12px;
  font-family: var(--font-display);
  font-style: italic;
}

.sidebar-search-wrap { position: relative; }

.sidebar-search-wrap svg {
  position: absolute;
  left: 10px;
  top: 50%;
  transform: translateY(-50%);
  width: 14px;
  height: 14px;
  color: var(--text-muted);
  pointer-events: none;
}

.sidebar-search {
  width: 100%;
  padding: 8px 12px 8px 32px;
  border: 1px solid var(--border);
  border-radius: 6px;
  font-size: 0.8rem;
  font-family: inherit;
  background: var(--bg-wash);
  color: var(--text);
  box-sizing: border-box;
  transition: border-color 0.2s, box-shadow 0.2s, background 0.2s;
}

.sidebar-search:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
  background: #fff;
}

.grammar-level.is-hidden,
.grammar-topic-list li.is-hidden { display: none; }

.grammar-level { margin-bottom: 2px; }

.grammar-level-title {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 10px 16px;
  font-weight: 600;
  font-size: 0.86rem;
  cursor: pointer;
  user-select: none;
  border: none;
  background: none;
  width: 100%;
  text-align: left;
  color: var(--ink);
  transition: background 0.15s;
  font-family: inherit;
}

.grammar-level-title:hover { background: var(--bg-wash); }

.grammar-level-title .level-badge {
  font-size: 0.62rem;
  padding: 2px 7px;
  border-radius: 4px;
  color: #fff;
  font-weight: 700;
  letter-spacing: 0.04em;
}

.level-beginner .level-badge { background: var(--green); }
.level-intermediate .level-badge { background: var(--accent); }
.level-advanced .level-badge { background: var(--purple); }

.grammar-level-title .arrow {
  margin-left: auto;
  transition: transform 0.2s;
  font-size: 0.65rem;
  color: var(--text-muted);
}

.grammar-level.open .grammar-level-title .arrow { transform: rotate(90deg); }

.grammar-topic-list {
  list-style: none;
  padding: 0;
  margin: 0 0 4px;
  display: none;
}

.grammar-level.open .grammar-topic-list { display: block; }

.grammar-topic-list li a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 16px 8px 28px;
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.84rem;
  border-left: 3px solid transparent;
  transition: all 0.15s;
  margin: 0 8px;
  border-radius: 0 6px 6px 0;
}

.grammar-topic-list li a em {
  font-style: normal;
  font-size: 0.68rem;
  color: var(--accent);
  font-weight: 600;
  background: var(--accent-soft);
  padding: 1px 7px;
  border-radius: 10px;
}

.grammar-topic-list li a:hover {
  background: var(--bg-wash);
  color: var(--navy);
}

.grammar-topic-list li a.active {
  background: var(--accent-soft);
  color: var(--accent);
  border-left-color: var(--accent);
  font-weight: 600;
}

/* ---------- Content ---------- */
.grammar-content {
  flex: 1;
  min-width: 0;
  padding: 28px 32px 40px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  color: var(--text);
}

.grammar-section { display: none; }
.grammar-section.active {
  display: block;
  animation: sectionIn 0.4s cubic-bezier(0.22, 1, 0.36, 1);
}

@keyframes sectionIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

.section-header {
  margin-bottom: 28px;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--border-soft);
  background: transparent;
}

.section-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 14px;
}

.meta-chip {
  display: inline-block;
  padding: 4px 11px;
  border-radius: 999px;
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.03em;
  background: var(--surface);
  color: var(--accent);
  border: 1px solid rgba(10, 110, 106, 0.2);
  box-shadow: 0 1px 2px rgba(15, 28, 46, 0.04);
}

.grammar-section h2 {
  font-family: var(--font-display);
  font-size: clamp(1.55rem, 2.5vw, 1.95rem);
  color: var(--navy) !important;
  margin: 0 0 8px;
  font-weight: 700;
  letter-spacing: -0.025em;
}

.section-subtitle {
  color: var(--text-muted) !important;
  font-size: 0.94rem;
  margin: 0;
  line-height: 1.55;
}

.level-tag {
  display: inline-block;
  font-size: 0.68rem;
  padding: 4px 12px;
  border-radius: 4px;
  color: #fff;
  margin-bottom: 14px;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.level-tag.beginner { background: var(--green); }
.level-tag.intermediate { background: var(--accent); }
.level-tag.advanced { background: var(--purple); }

/* Cards */
.rule-card {
  background: var(--surface);
  border-radius: var(--radius);
  padding: 22px 26px;
  margin-bottom: 20px;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
  border-left: 4px solid var(--accent);
  line-height: 1.75;
}

.rule-card.compact {
  padding: 16px 22px;
  border-left-width: 3px;
}

.rule-card.compact p { margin: 0; font-size: 0.92rem; }

.rule-card h3 {
  color: var(--accent);
  font-size: 0.95rem;
  margin: 0 0 12px;
  font-weight: 700;
  letter-spacing: 0.02em;
}

.rule-card ul {
  padding-left: 1.25em;
  margin: 8px 0 0;
}

.rule-card li {
  margin-bottom: 6px;
  font-size: 0.92rem;
}

.rule-card li::marker { color: var(--accent); }

.rule-card code {
  background: var(--bg-wash);
  padding: 2px 7px;
  border-radius: 4px;
  font-size: 0.84em;
  color: var(--navy);
  border: 1px solid var(--border-soft);
  font-family: 'IBM Plex Mono', 'Consolas', monospace;
}

.rule-card em {
  color: var(--accent);
  font-style: normal;
  font-weight: 600;
  font-family: var(--font-display);
}

/* Structure grid */
.structure-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 14px;
  margin: 8px 0 28px;
}

.structure-card {
  background: var(--surface);
  border-radius: var(--radius);
  padding: 20px 18px 18px;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
  position: relative;
  overflow: hidden;
  transition: transform 0.25s ease, box-shadow 0.25s ease, border-color 0.25s;
  animation: fadeUp 0.5s ease both;
}

.structure-card:nth-child(1) { animation-delay: 0.05s; border-top: 3px solid #0d6b4c; }
.structure-card:nth-child(2) { animation-delay: 0.1s; border-top: 3px solid var(--accent); }
.structure-card:nth-child(3) { animation-delay: 0.15s; border-top: 3px solid #1a6bb5; }
.structure-card:nth-child(4) { animation-delay: 0.2s; border-top: 3px solid var(--orange); }
.structure-card:nth-child(5) { animation-delay: 0.25s; border-top: 3px solid var(--purple); }

.structure-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: transparent;
}

.structure-card h4 {
  margin: 0 0 10px;
  color: var(--navy);
  font-size: 0.92rem;
  font-weight: 700;
}

.structure-formula {
  display: inline-block;
  background: var(--bg-wash);
  color: var(--navy);
  font-weight: 700;
  padding: 4px 11px;
  border-radius: 5px;
  font-size: 0.86rem;
  margin-bottom: 10px;
  font-family: var(--font-display);
  border: 1px solid var(--border-soft);
  letter-spacing: 0.02em;
}

.structure-card p {
  margin: 4px 0;
  font-size: 0.82rem;
  color: var(--text-muted);
  line-height: 1.5;
}

.structure-card .example-en {
  font-family: var(--font-display);
  color: var(--navy);
  font-weight: 600;
  font-size: 0.95rem;
  margin-top: 12px;
  padding-top: 10px;
  border-top: 1px dashed var(--border-soft);
}

/* Tables */
.example-table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0;
  margin: 8px 0 20px;
  font-size: 0.9rem;
  background: var(--surface);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
}

.example-table th,
.example-table td {
  padding: 13px 18px;
  text-align: left;
  border-bottom: 1px solid var(--border-soft);
}

.example-table tr:last-child td { border-bottom: none; }

.example-table tbody tr {
  transition: background 0.15s;
}

.example-table tbody tr:hover { background: #f7faf9; }

.example-table th {
  background: var(--navy);
  color: #fff;
  font-weight: 600;
  font-size: 0.78rem;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.example-table td:first-child {
  font-weight: 700;
  color: var(--accent);
  white-space: nowrap;
  font-family: var(--font-display);
  font-size: 0.88rem;
}

.compare-table td:nth-child(2),
.compare-table td:nth-child(3) {
  font-family: var(--font-display);
  color: var(--navy);
}

/* Tip */
.tip-box {
  background: linear-gradient(135deg, rgba(13, 107, 76, 0.06), rgba(10, 110, 106, 0.04));
  border-left: 4px solid var(--green);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  padding: 16px 20px;
  margin: 20px 0;
  font-size: 0.92rem;
  line-height: 1.7;
  border: 1px solid rgba(13, 107, 76, 0.12);
  border-left-width: 4px;
}

.tip-box strong { color: var(--green); }

.mistake-box {
  background: rgba(185, 28, 28, 0.04);
  border-left: 4px solid #b91c1c;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  padding: 14px 18px;
  margin: 16px 0;
  font-size: 0.9rem;
}

.mistake-box .wrong { color: #b91c1c; text-decoration: line-through; }
.mistake-box .right { color: var(--green); font-weight: 600; }

/* Adverb overview */
.adverb-overview {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
  gap: 10px;
  margin-bottom: 20px;
}

.overview-chip {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 12px 14px;
  font-size: 0.82rem;
  box-shadow: var(--shadow);
  color: var(--text-muted);
  transition: border-color 0.2s, transform 0.2s;
}

.overview-chip:hover {
  border-color: rgba(91, 45, 142, 0.35);
  transform: translateY(-1px);
}

.overview-chip strong {
  display: block;
  color: var(--purple);
  margin-bottom: 4px;
  font-size: 0.78rem;
  letter-spacing: 0.03em;
}

/* ---------- Vocabulary ---------- */
.vocab-bank { margin: 20px 0; }

.vocab-toolbar {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px 16px;
  margin-bottom: 14px;
  box-shadow: var(--shadow);
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-items: center;
  position: sticky;
  top: 12px;
  z-index: 10;
  backdrop-filter: blur(8px);
}

.vocab-search-wrap {
  flex: 1;
  min-width: 200px;
  position: relative;
}

.vocab-search-wrap svg {
  position: absolute;
  left: 12px;
  top: 50%;
  transform: translateY(-50%);
  width: 16px;
  height: 16px;
  color: var(--text-muted);
  pointer-events: none;
}

.vocab-search {
  width: 100%;
  padding: 10px 14px 10px 38px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 0.88rem;
  font-family: inherit;
  color: var(--text);
  background: var(--bg-wash);
  transition: border-color 0.2s, box-shadow 0.2s, background 0.2s;
  box-sizing: border-box;
}

.vocab-search:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
  background: #fff;
}

.vocab-meta {
  font-size: 0.8rem;
  color: var(--text-muted);
  white-space: nowrap;
  padding: 6px 12px;
  background: var(--bg-wash);
  border-radius: 999px;
  border: 1px solid var(--border-soft);
}

.vocab-meta strong {
  color: var(--accent);
  font-weight: 700;
}

.vocab-alpha {
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
  margin-bottom: 12px;
  padding: 4px 0;
}

.vocab-alpha-btn {
  width: 28px;
  height: 28px;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: var(--surface);
  color: var(--text-muted);
  font-size: 0.74rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.15s;
  padding: 0;
  font-family: inherit;
}

.vocab-alpha-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--accent-soft);
}

.vocab-alpha-btn.active {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}

.vocab-alpha-btn.disabled {
  opacity: 0.28;
  cursor: default;
  pointer-events: none;
}

.vocab-tag-filter {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 14px;
}

.vocab-tag-btn {
  padding: 5px 12px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--surface);
  color: var(--text-muted);
  font-size: 0.76rem;
  cursor: pointer;
  transition: all 0.15s;
  font-family: inherit;
}

.vocab-tag-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.vocab-tag-btn.active {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}

.vocab-table-wrap {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
}

.vocab-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.88rem;
}

.vocab-table thead {
  background: var(--navy);
  color: #fff;
}

.vocab-table th {
  padding: 12px 16px;
  text-align: left;
  font-weight: 600;
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.vocab-table td {
  padding: 11px 16px;
  border-bottom: 1px solid var(--border-soft);
  vertical-align: middle;
}

.vocab-table tbody tr { transition: background 0.12s; }
.vocab-table tbody tr:nth-child(even) { background: #f8fafb; }
.vocab-table tbody tr:hover { background: #eef7f6; }
.vocab-table tbody tr:last-child td { border-bottom: none; }

.vocab-table .col-num {
  color: var(--text-muted);
  font-size: 0.74rem;
  width: 48px;
  font-variant-numeric: tabular-nums;
}

.vocab-table .col-en {
  font-family: var(--font-display);
  font-weight: 600;
  color: var(--navy);
  font-size: 0.98rem;
  letter-spacing: -0.01em;
}

.vocab-table .col-cn { color: var(--text); }
.vocab-table .col-tag { font-size: 0.75rem; }

.vocab-tag-pill {
  display: inline-block;
  padding: 2px 9px;
  border-radius: 999px;
  font-size: 0.7rem;
  font-weight: 600;
  background: rgba(91, 45, 142, 0.08);
  color: var(--purple);
  border: 1px solid rgba(91, 45, 142, 0.12);
}

.vocab-bank[data-color="green"] .vocab-table thead { background: var(--green); }
.vocab-bank[data-color="green"] .vocab-meta strong { color: var(--green); }
.vocab-bank[data-color="green"] .vocab-alpha-btn.active,
.vocab-bank[data-color="green"] .vocab-tag-btn.active {
  background: var(--green); border-color: var(--green);
}
.vocab-bank[data-color="green"] .vocab-search:focus {
  border-color: var(--green);
  box-shadow: 0 0 0 3px rgba(13, 107, 76, 0.12);
}

.vocab-bank[data-color="orange"] .vocab-table thead { background: var(--orange); }
.vocab-bank[data-color="orange"] .vocab-meta strong { color: var(--orange); }
.vocab-bank[data-color="orange"] .vocab-alpha-btn.active {
  background: var(--orange); border-color: var(--orange);
}

.vocab-bank[data-color="purple"] .vocab-table thead { background: var(--purple); }
.vocab-bank[data-color="purple"] .vocab-meta strong { color: var(--purple); }
.vocab-bank[data-color="purple"] .vocab-alpha-btn.active,
.vocab-bank[data-color="purple"] .vocab-tag-btn.active {
  background: var(--purple); border-color: var(--purple);
}

.vocab-bank[data-color="teal"] .vocab-table thead { background: var(--teal); }
.vocab-bank[data-color="teal"] .vocab-meta strong { color: var(--teal); }
.vocab-bank[data-color="teal"] .vocab-alpha-btn.active,
.vocab-bank[data-color="teal"] .vocab-tag-btn.active {
  background: var(--teal); border-color: var(--teal);
}

.vocab-empty {
  text-align: center;
  padding: 56px 20px;
  color: var(--text-muted);
  font-size: 0.9rem;
}

.vocab-pagination {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  margin-top: 18px;
  padding: 8px 0;
}

.vocab-page-btn {
  padding: 7px 16px;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: var(--surface);
  color: var(--text);
  font-size: 0.82rem;
  cursor: pointer;
  transition: all 0.15s;
  font-family: inherit;
  font-weight: 500;
}

.vocab-page-btn:hover:not(:disabled) {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--accent-soft);
}

.vocab-page-btn:disabled {
  opacity: 0.4;
  cursor: default;
}

.vocab-page-info {
  font-size: 0.82rem;
  color: var(--text-muted);
  padding: 0 10px;
  font-variant-numeric: tabular-nums;
}

/* ---------- Quiz ---------- */
.quiz-box {
  background: var(--surface);
  border-radius: var(--radius);
  padding: 26px 28px;
  margin-top: 36px;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
  border-top: 3px solid var(--accent);
}

.quiz-box h3 {
  color: var(--navy);
  margin: 0 0 16px;
  font-size: 1.05rem;
  font-weight: 700;
  font-family: var(--font-display);
}

.quiz-score {
  text-align: right;
  color: var(--text-muted);
  font-size: 0.84rem;
  margin-bottom: 14px;
  font-variant-numeric: tabular-nums;
}

.quiz-question { margin-bottom: 20px; }

.quiz-question-text {
  font-size: 0.96rem;
  font-weight: 600;
  margin-bottom: 12px;
  color: var(--text);
  line-height: 1.5;
}

.quiz-options {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 8px;
}

.quiz-options li {
  background: var(--bg-wash);
  padding: 12px 16px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-size: 0.9rem;
  transition: all 0.15s;
  border: 1px solid var(--border-soft);
}

.quiz-options li:hover:not(.answered) {
  background: var(--accent-soft);
  border-color: rgba(10, 110, 106, 0.25);
  transform: translateX(2px);
}

.quiz-options li.selected { background: var(--accent); color: #fff; border-color: var(--accent); }
.quiz-options li.correct {
  background: rgba(13, 107, 76, 0.1);
  color: var(--green);
  border-color: var(--green);
}
.quiz-options li.wrong {
  background: rgba(185, 28, 28, 0.06);
  color: #b91c1c;
  border-color: #dc2626;
}
.quiz-options li.answered { cursor: default; }

.quiz-finish {
  text-align: center;
  margin-top: 16px;
  padding: 20px;
  background: var(--bg-wash);
  border-radius: var(--radius-sm);
  font-size: 0.95rem;
  color: var(--navy);
  display: none;
  border: 1px solid var(--border-soft);
}

.quiz-finish.visible { display: block; }

.quiz-retry-btn {
  display: inline-block;
  margin-top: 14px;
  padding: 9px 28px;
  font-size: 0.88rem;
  border-radius: 6px;
  border: 2px solid var(--accent);
  background: #fff;
  color: var(--accent);
  cursor: pointer;
  font-weight: 600;
  transition: all 0.2s;
  font-family: inherit;
}

.quiz-retry-btn:hover {
  background: var(--accent);
  color: #fff;
}

/* ---------- Responsive ---------- */
@media (max-width: 900px) {
  .grammar-mobile-toggle { display: flex; }

  .grammar-hero { padding: 36px 24px 32px; }
  .grammar-hero-inner { align-items: flex-start; }
  .grammar-container {
    flex-direction: column;
    margin-top: 0;
    padding: 16px 16px 48px;
    gap: 0;
  }

  .grammar-sidebar {
    position: fixed;
    top: 0;
    left: 0;
    z-index: 200;
    width: min(300px, 88vw);
    min-width: 0;
    max-height: 100vh;
    height: 100vh;
    border-radius: 0;
    transform: translateX(-105%);
    transition: transform 0.28s ease;
    box-shadow: var(--shadow-lg);
  }

  .grammar-sidebar.is-open { transform: translateX(0); }

  .grammar-sidebar-backdrop {
    display: block;
    position: fixed;
    inset: 0;
    z-index: 199;
    background: rgba(15, 28, 46, 0.45);
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.28s ease;
  }

  .grammar-sidebar-backdrop.is-visible {
    opacity: 1;
    pointer-events: auto;
  }

  .grammar-content {
    padding: 22px 18px 36px;
    border-radius: var(--radius-sm);
  }
  .grammar-hero-stats { width: 100%; }
  .vocab-toolbar { position: relative; top: 0; }
  .structure-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 600px) {
  .grammar-hero { padding: 28px 18px; }
  .grammar-hero-text h1 { font-size: 1.45rem; }
  .hero-stat { min-width: 68px; padding: 12px 10px; }
  .hero-stat-num { font-size: 1.35rem; }
  .structure-grid { grid-template-columns: 1fr; }
  .vocab-table .col-num { display: none; }
  .vocab-alpha-btn { width: 26px; height: 26px; font-size: 0.7rem; }
  .adverb-overview { grid-template-columns: 1fr 1fr; }
  .quiz-box { padding: 20px; }
}

@media (prefers-reduced-motion: reduce) {
  .grammar-section.active,
  .hero-stat,
  .structure-card,
  .grammar-hero-badge::before {
    animation: none;
  }
}