* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 150px; }
body { margin: 0; color: var(--color-text); background: var(--color-bg); font-family: var(--font-sans); line-height: 1.65; }
button, input, select { font: inherit; }
button { cursor: pointer; }
.container { width: min(100% - 3rem, 1200px); margin-inline: auto; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }

.glossary-hero {
    padding: 4.25rem 0 3rem;
    color: #fff;
    background: var(--color-primary-hover);
    border-bottom: 1px solid rgba(255,255,255,.12);
}
.breadcrumbs { display: flex; flex-wrap: wrap; gap: .45rem; margin-bottom: 2.5rem; color: rgba(255,255,255,.68); font-size: .82rem; }
.breadcrumbs a { color: rgba(255,255,255,.88); text-decoration: none; }
.breadcrumbs a:hover { text-decoration: underline; text-underline-offset: 3px; }
.hero-copy { max-width: 850px; margin: 0 auto; text-align: center; }
.eyebrow, .section-kicker { margin: 0 0 .55rem; color: var(--color-accent-text); font-size: .76rem; font-weight: 800; letter-spacing: .13em; text-transform: uppercase; }
.glossary-hero .eyebrow { color: var(--color-accent); }
.glossary-hero h1 { margin: 0; color: #fff; font-size: clamp(2rem, 5vw, 3.5rem); line-height: 1.18; letter-spacing: -.035em; }
.hero-subtitle { margin: .8rem 0 0; color: rgba(255,255,255,.82); font-size: clamp(1rem, 2vw, 1.2rem); }
.data-summary { margin: 1.35rem 0 0; color: rgba(255,255,255,.72); font-size: .9rem; }
.data-summary strong { color: #fff; }
.data-summary span { margin-inline: .3rem; opacity: .45; }

.hero-search { display: grid; grid-template-columns: 1fr auto; max-width: 820px; margin: 2rem auto 0; padding: .4rem; border: 1px solid rgba(255,255,255,.24); border-radius: 12px; background: #fff; box-shadow: 0 18px 45px rgba(0,0,0,.18); }
.hero-search input { min-width: 0; min-height: 52px; padding: .7rem 1rem; border: 0; outline: 0; color: var(--color-text); background: transparent; font-size: 1rem; }
.hero-search button { min-width: 112px; min-height: 52px; padding: .65rem 1.2rem; border: 0; border-radius: 8px; background: var(--color-primary); color: #fff; font-weight: 800; }
.hero-search button:hover { background: var(--color-primary-hover); }
.search-help { max-width: 780px; margin: .7rem auto 0; color: rgba(255,255,255,.58); text-align: center; font-size: .76rem; }
.quick-searches { display: flex; justify-content: center; align-items: center; flex-wrap: wrap; gap: .4rem; max-width: 900px; margin: 1.15rem auto 0; color: rgba(255,255,255,.62); font-size: .78rem; }
.quick-searches button { min-height: 34px; padding: .25rem .65rem; border: 1px solid rgba(255,255,255,.22); border-radius: 999px; background: rgba(255,255,255,.08); color: #fff; }
.quick-searches button:hover { border-color: var(--color-accent); background: rgba(255,255,255,.13); }
.hero-actions { display: flex; justify-content: center; align-items: center; flex-wrap: wrap; gap: .85rem 1.1rem; margin-top: 1.5rem; color: rgba(255,255,255,.62); font-size: .78rem; }
.hero-actions .btn { background: var(--color-accent); color: var(--color-primary-hover); }

.glossary-sticky { position: sticky; top: 0; z-index: 20; border-bottom: 1px solid var(--color-border); background: rgba(247,248,246,.96); backdrop-filter: blur(12px); }
.site-shell-header + main .glossary-sticky { top: 68px; }
.glossary-tabs { display: flex; gap: .25rem; overflow-x: auto; scrollbar-width: thin; }
.glossary-tabs button { min-height: 54px; padding: .7rem 1rem; border: 0; border-bottom: 3px solid transparent; background: transparent; color: var(--color-text-secondary); white-space: nowrap; font-weight: 750; }
.glossary-tabs button span { color: var(--color-text-muted); font-size: .72rem; }
.glossary-tabs button[aria-selected="true"] { border-bottom-color: var(--color-accent-text); color: var(--color-primary); }

.glossary-section { padding: 3.75rem 0 4.5rem; }
.glossary-section[hidden] { display: none; }
.query-layout { display: grid; grid-template-columns: 250px minmax(0, 1fr); gap: 2.2rem; align-items: start; }
.filter-column { position: sticky; top: 145px; }
.filter-panel { border: 1px solid var(--color-border); border-radius: 12px; background: var(--color-surface); overflow: hidden; box-shadow: var(--shadow-sm); }
.filter-panel summary { display: flex; justify-content: space-between; align-items: center; min-height: 52px; padding: .8rem 1rem; color: var(--color-primary); font-weight: 800; cursor: pointer; list-style: none; }
.filter-panel summary::-webkit-details-marker { display: none; }
.filter-panel summary::after { content: "−"; color: var(--color-text-muted); font-size: 1.2rem; }
.filter-panel:not([open]) summary::after { content: "+"; }
.filter-panel summary span { margin-left: auto; margin-right: .5rem; color: var(--color-accent-text); font-size: .72rem; }
.filter-fields { display: grid; gap: .55rem; padding: .25rem 1rem 1rem; border-top: 1px solid var(--color-border-light); }
.filter-fields > label:not(.check-field) { margin-top: .55rem; color: var(--color-text-secondary); font-size: .75rem; font-weight: 700; }
.filter-fields select, .sort-field select { width: 100%; min-height: 44px; padding: .55rem .65rem; border: 1px solid var(--color-border); border-radius: 7px; background: var(--color-surface); color: var(--color-text); }
.check-field { display: flex; align-items: center; gap: .55rem; min-height: 42px; color: var(--color-text-secondary); font-size: .8rem; }
.check-field input { width: 18px; height: 18px; accent-color: var(--color-primary); }
.clear-filters { min-height: 42px; margin-top: .4rem; border: 1px solid var(--color-border); border-radius: 7px; background: var(--color-surface-muted); color: var(--color-primary); font-weight: 700; }

.results-heading { display: flex; justify-content: space-between; align-items: end; gap: 1rem; margin-bottom: 1.3rem; }
.results-heading h2, .narrow-section h2, .learning-section h2, .download-panel h2, .notes-grid h2 { margin: 0; color: var(--color-primary-hover); font-size: clamp(1.65rem, 3vw, 2.2rem); line-height: 1.25; }
.result-summary, .section-intro { margin: .5rem 0 0; color: var(--color-text-secondary); font-size: .88rem; }
.sort-field { width: 150px; color: var(--color-text-secondary); font-size: .72rem; font-weight: 700; }
.sort-field select { display: block; margin-top: .25rem; }
.status-message { margin-bottom: 1rem; padding: .85rem 1rem; border: 1px solid var(--color-border); border-radius: 8px; background: var(--color-surface-muted); color: var(--color-text-secondary); }
.status-message.error { border-color: #d6a9a9; background: #fff4f4; color: #7b2929; }

.term-results { display: grid; gap: .8rem; }
.term-card { scroll-margin-top: 160px; border: 1px solid var(--color-border); border-radius: 10px; background: var(--color-surface); box-shadow: var(--shadow-sm); overflow: hidden; }
.term-card.is-open { border-color: rgba(18,59,74,.34); box-shadow: var(--shadow-md); }
.term-card-summary { width: 100%; display: grid; grid-template-columns: minmax(0,1fr) auto; gap: 1rem; align-items: start; padding: 1.15rem 1.25rem; border: 0; background: transparent; color: inherit; text-align: left; cursor: pointer; list-style: none; }
.term-card-summary::-webkit-details-marker { display: none; }
.term-card-summary:hover { background: var(--color-surface-muted); }
.term-category { margin: 0 0 .28rem; color: var(--color-text-muted); font-size: .72rem; }
.term-card h3 { margin: 0; color: var(--color-primary-hover); font-size: 1.08rem; line-height: 1.45; overflow-wrap: anywhere; }
.abbr-badge { display: inline-flex; align-items: center; min-height: 24px; margin-left: .35rem; padding: .1rem .45rem; border: 1px solid rgba(18,59,74,.18); border-radius: 999px; background: var(--color-primary-soft); color: var(--color-primary); font-size: .66rem; vertical-align: .12em; }
.term-chinese { margin: .28rem 0 .15rem; color: var(--color-accent-text); font-weight: 750; }
.term-definition { display: -webkit-box; margin: 0; overflow: hidden; color: var(--color-text-secondary); font-size: .84rem; -webkit-line-clamp: 2; -webkit-box-orient: vertical; }
.importance-badge { display: inline-flex; min-width: 46px; justify-content: center; padding: .18rem .48rem; border-radius: 999px; font-size: .68rem; font-weight: 800; }
.importance-core { background: #e5f1ed; color: #1d624f; }
.importance-common { background: #eef1f3; color: #415563; }
.importance-advanced { background: #f5eedf; color: #77551a; }
.expand-indicator { display: block; margin-top: .7rem; color: var(--color-text-muted); font-size: .72rem; text-align: right; }
.term-details { padding: 0 1.25rem 1.25rem; border-top: 1px solid var(--color-border-light); }
.term-detail-grid { display: grid; grid-template-columns: repeat(2, minmax(0,1fr)); gap: .85rem 1.5rem; padding-top: 1rem; }
.term-detail { min-width: 0; }
.term-detail dt { color: var(--color-text-muted); font-size: .7rem; font-weight: 700; }
.term-detail dd { margin: .15rem 0 0; color: var(--color-text-secondary); font-size: .84rem; overflow-wrap: anywhere; }
.term-detail a { color: var(--color-primary); text-decoration: underline; text-underline-offset: 3px; }
.term-actions { display: flex; flex-wrap: wrap; gap: .5rem; margin-top: 1rem; }
.term-actions button, .term-actions a { min-height: 40px; display: inline-flex; align-items: center; padding: .45rem .75rem; border: 1px solid var(--color-border); border-radius: 7px; background: var(--color-surface); color: var(--color-primary); text-decoration: none; font-size: .76rem; font-weight: 700; }
.related-terms { margin-top: 1rem; padding-top: .9rem; border-top: 1px solid var(--color-border-light); color: var(--color-text-secondary); font-size: .78rem; }
.related-terms button { margin: .2rem .2rem 0 0; padding: .25rem .5rem; border: 0; border-radius: 999px; background: var(--color-primary-soft); color: var(--color-primary); }
mark { padding: 0 .08em; border-radius: 2px; background: #ffedb3; color: inherit; }
.load-more-wrap { display: flex; justify-content: center; margin-top: 1.4rem; }
.empty-state { padding: 3rem 1.5rem; border: 1px dashed var(--color-border-strong); border-radius: 10px; text-align: center; color: var(--color-text-secondary); }
.empty-state h3 { margin: 0 0 .5rem; color: var(--color-primary-hover); }

.narrow-section, .learning-section { max-width: 1040px; }
.abbreviation-grid { display: grid; grid-template-columns: repeat(2, minmax(0,1fr)); gap: .8rem; margin-top: 1.5rem; }
.abbreviation-card { padding: 1rem 1.1rem; border: 1px solid var(--color-border); border-radius: 9px; background: var(--color-surface); }
.abbreviation-card h3 { display: flex; align-items: center; gap: .5rem; margin: 0 0 .35rem; color: var(--color-primary); font-size: 1.15rem; }
.multi-meaning { padding: .12rem .45rem; border-radius: 999px; background: var(--color-warning-soft); color: #754b0f; font-size: .62rem; }
.abbreviation-card .english-full { margin: 0; color: var(--color-primary-hover); font-weight: 700; }
.abbreviation-card .chinese-full { margin: .2rem 0; color: var(--color-accent-text); }
.abbreviation-card .abbr-description { margin: .5rem 0 0; color: var(--color-text-secondary); font-size: .8rem; }
.abbreviation-card .abbr-meta { margin: .55rem 0 0; color: var(--color-text-muted); font-size: .7rem; }

.confusion-grid { display: grid; gap: .85rem; margin-top: 1.5rem; }
.confusion-card { border: 1px solid var(--color-border); border-radius: 10px; background: var(--color-surface); }
.confusion-card summary { min-height: 58px; padding: .95rem 1.1rem; color: var(--color-primary-hover); font-weight: 800; cursor: pointer; }
.confusion-body { display: grid; grid-template-columns: minmax(180px,.75fr) minmax(0,1.4fr); gap: 1rem; padding: 0 1.1rem 1.1rem; border-top: 1px solid var(--color-border-light); }
.confusion-body div { padding-top: .9rem; }
.confusion-body strong { display: block; color: var(--color-text-muted); font-size: .7rem; }
.confusion-body p { margin: .25rem 0 0; color: var(--color-text-secondary); }

.learning-toolbar { display: flex; justify-content: space-between; align-items: center; gap: 1rem; margin-top: 1.4rem; }
.learning-toolbar p { margin: 0; color: var(--color-text-secondary); font-weight: 700; }
.segmented { display: inline-flex; padding: .22rem; border: 1px solid var(--color-border); border-radius: 8px; background: var(--color-surface-muted); }
.segmented button { min-height: 38px; padding: .4rem .75rem; border: 0; border-radius: 6px; background: transparent; color: var(--color-text-secondary); }
.segmented button.active { background: var(--color-surface); color: var(--color-primary); box-shadow: var(--shadow-sm); font-weight: 800; }
.learning-grid { display: grid; grid-template-columns: repeat(2, minmax(0,1fr)); gap: .85rem; margin-top: 1rem; }
.learning-card { display: grid; gap: .75rem; align-content: start; min-height: 220px; padding: 1.1rem; border: 1px solid var(--color-border); border-radius: 10px; background: var(--color-surface); }
.learning-card.is-known { border-color: #a6cfbb; background: #f4faf7; }
.learning-card.is-review { border-color: #e3c787; background: #fffaf0; }
.learning-number { margin: 0; color: var(--color-text-muted); font-size: .7rem; font-weight: 700; }
.learning-card h3 { margin: 0; color: var(--color-primary-hover); font-size: 1.1rem; }
.learning-answer { margin: 0; color: var(--color-text-secondary); font-size: .83rem; }
.learning-answer[hidden] { display: none; }
.learning-actions { display: flex; flex-wrap: wrap; gap: .4rem; margin-top: auto; }
.learning-actions button { min-height: 38px; padding: .4rem .65rem; border: 1px solid var(--color-border); border-radius: 7px; background: var(--color-surface); color: var(--color-primary); font-size: .74rem; font-weight: 700; }

.download-section { padding: 3.5rem 0; background: var(--color-primary-hover); color: #fff; }
.download-panel { display: grid; grid-template-columns: minmax(0,1fr) auto; align-items: center; gap: 2rem; }
.download-panel h2 { color: #fff; }
.download-panel p { max-width: 720px; margin: .6rem 0 0; color: rgba(255,255,255,.7); }
.download-guide { padding: .55rem .7rem; border-left: 3px solid var(--color-accent); background: rgba(255,255,255,.06); }
.download-actions { display: grid; gap: .6rem; text-align: center; }
.download-actions .btn { background: var(--color-accent); color: var(--color-primary-hover); }
.text-link { color: rgba(255,255,255,.82); font-size: .78rem; text-decoration: underline; text-underline-offset: 3px; }
.glossary-notes { padding: 3.5rem 0; }
.notes-grid { display: grid; grid-template-columns: repeat(2,minmax(0,1fr)); gap: 1rem; }
.notes-grid > div { padding: 1.25rem; border: 1px solid var(--color-border); border-radius: 10px; background: var(--color-surface); }
.notes-grid h2 { font-size: 1.2rem; }
.notes-grid p { margin: .65rem 0 0; color: var(--color-text-secondary); font-size: .82rem; }
.disclaimer { border-left: 4px solid var(--color-accent-text) !important; }

@media (max-width: 900px) {
    .query-layout { grid-template-columns: 1fr; gap: 1rem; }
    .filter-column { position: static; }
    .filter-panel:not([open]) .filter-fields { display: none; }
    .filter-fields { grid-template-columns: repeat(2,minmax(0,1fr)); align-items: end; }
    .filter-fields .clear-filters { align-self: end; }
    .site-shell-header + main .glossary-sticky { top: 68px; }
}

@media (max-width: 700px) {
    .container { width: min(100% - 2rem, 1200px); }
    .glossary-hero { padding: 2.6rem 0 2.25rem; }
    .breadcrumbs { margin-bottom: 1.6rem; }
    .hero-search { grid-template-columns: 1fr; padding: .35rem; }
    .hero-search button { width: 100%; min-height: 46px; }
    .quick-searches { justify-content: flex-start; overflow-x: auto; flex-wrap: nowrap; padding-bottom: .35rem; }
    .quick-searches span, .quick-searches button { flex: 0 0 auto; }
    .glossary-tabs { margin-inline: -1rem; padding-inline: 1rem; }
    .glossary-tabs button { min-height: 50px; padding-inline: .75rem; }
    .glossary-section { padding: 2.5rem 0 3.25rem; }
    .filter-panel:not([open]) .filter-fields { display: none; }
    .filter-fields { grid-template-columns: 1fr; }
    .results-heading { align-items: stretch; flex-direction: column; }
    .sort-field { width: 100%; }
    .term-card-summary { grid-template-columns: 1fr; padding: 1rem; }
    .term-card-summary > div:last-child { display: flex; align-items: center; justify-content: space-between; }
    .expand-indicator { margin-top: 0; }
    .term-details { padding: 0 1rem 1rem; }
    .term-detail-grid, .confusion-body { grid-template-columns: 1fr; }
    .abbreviation-grid, .learning-grid { grid-template-columns: 1fr; }
    .learning-toolbar { align-items: stretch; flex-direction: column; }
    .segmented { width: 100%; }
    .segmented button { flex: 1; }
    .download-panel, .notes-grid { grid-template-columns: 1fr; }
    .download-actions { text-align: left; }
}

@media (max-width: 420px) {
    .container { width: min(100% - 1.4rem, 1200px); }
    .glossary-tabs { margin-inline: -.7rem; padding-inline: .7rem; }
    .data-summary span { display: none; }
    .data-summary strong:not(:first-child)::before { content: " · "; color: rgba(255,255,255,.4); }
    .term-actions button, .term-actions a { flex: 1 1 42%; justify-content: center; }
}

@media (prefers-reduced-motion: reduce) {
    html { scroll-behavior: auto; }
    *, *::before, *::after { scroll-behavior: auto !important; transition-duration: .01ms !important; }
}