:root {
  --ink: #172427;
  --muted: #667477;
  --line: #dce4e2;
  --paper: #f7f9f8;
  --card: #fff;
  --accent: #116466;
  --accent-soft: #e1f1ef;
  --radius: 15px;
  --toolbar-offset: 122px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; background: var(--paper); color: var(--ink); font: 16px/1.55 ui-sans-serif, -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", sans-serif; }
.shell { width: min(1180px, calc(100% - 40px)); margin: auto; }
.site-header { border-bottom: 1px solid var(--line); }
.site-header .shell { height: 58px; display: flex; align-items: center; gap: 16px; }
.brand { display: inline-flex; align-items: baseline; gap: 8px; color: var(--accent); text-decoration: none; white-space: nowrap; }
.brand-cn { font-size: 21px; font-weight: 800; letter-spacing: -.05em; }
.brand-en { color: var(--muted); font-size: 12px; font-weight: 700; letter-spacing: .04em; }
.site-header p { margin: 0; color: var(--muted); font-size: 14px; }
.intro { max-width: 720px; padding: 28px 0 15px; }
.eyebrow { margin: 0 0 6px; color: var(--accent); font-size: 12px; font-weight: 700; letter-spacing: .12em; }
.intro h1 { margin: 0; font-size: clamp(30px, 3.8vw, 44px); letter-spacing: -.06em; line-height: 1.13; }
.lede { max-width: 630px; margin: 9px 0 0; color: var(--muted); font-size: 15px; }

.directory-toolbar { position: sticky; top: 0; z-index: 10; margin: 0 -12px; padding: 9px 12px 8px; background: rgba(247, 249, 248, .97); border-bottom: 1px solid var(--line); box-shadow: 0 7px 16px rgba(23, 36, 39, .05); backdrop-filter: blur(10px); }
.search-row, .category-row { display: flex; align-items: center; gap: 9px; }
.search { min-width: 0; flex: 1; display: flex; align-items: center; gap: 9px; padding: 0 12px; background: var(--card); border: 1px solid var(--line); border-radius: 12px; }
.search:focus-within { border-color: var(--accent); outline: 3px solid rgba(17, 100, 102, .18); }
.search-mark { color: var(--accent); font-size: 24px; }
.search input { width: 100%; padding: 10px 0; color: var(--ink); background: transparent; border: 0; outline: 0; font: inherit; }
kbd { padding: 1px 5px; color: var(--muted); border: 1px solid var(--line); border-radius: 5px; font-size: 12px; }
.clear-search { flex: 0 0 auto; padding: 9px 11px; color: var(--accent); background: var(--card); border: 1px solid var(--line); border-radius: 10px; cursor: pointer; font: 700 13px/1.35 inherit; }
.clear-search:hover, .clear-search:focus-visible { border-color: var(--accent); outline: 3px solid rgba(17, 100, 102, .18); outline-offset: 1px; }
.category-row { margin-top: 7px; }
.category-nav { flex: 1; display: flex; gap: 7px; min-width: 0; padding: 0 1px 1px; overflow-x: auto; scrollbar-color: #b7ccc8 transparent; scrollbar-width: thin; }
.category-nav a { flex: 0 0 auto; padding: 5px 10px; color: var(--muted); border: 1px solid var(--line); border-radius: 999px; font-size: 13px; text-decoration: none; }
.category-nav a:hover, .category-nav a:focus-visible, .category-nav a.is-active { color: var(--accent); background: var(--accent-soft); border-color: var(--accent); outline: none; }
.search-result { flex: 0 0 auto; margin: 0; color: var(--muted); font-size: 12px; white-space: nowrap; }

.category { padding: 19px 0; border-top: 1px solid var(--line); scroll-margin-top: var(--toolbar-offset); }
.category-heading { display: flex; align-items: baseline; gap: 13px; margin-bottom: 10px; }
.category h2, .about h2, .projects h2 { margin: 0; font-size: 20px; letter-spacing: -.04em; }
.category-heading p { margin: 0; color: var(--muted); font-size: 14px; }
.cards { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 10px; }
.card { display: flex; gap: 11px; padding: 13px; color: inherit; background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); text-decoration: none; transition: transform .16s, border-color .16s, box-shadow .16s; }
.card:hover { border-color: #9ec5c1; box-shadow: 0 7px 18px rgba(17, 100, 102, .08); transform: translateY(-2px); }
.card:focus-visible { outline: 3px solid rgba(17, 100, 102, .3); outline-offset: 2px; }
.monogram { display: grid; flex: 0 0 32px; height: 32px; place-items: center; color: var(--accent); background: var(--accent-soft); border-radius: 9px; font-weight: 800; }
.card h3 { margin: 0 0 3px; font-size: 15px; letter-spacing: -.02em; }
.card h3 b { color: var(--accent); font-size: 12px; }
.card p { margin: 0 0 5px; color: var(--muted); font-size: 13px; }
.card small { color: #819091; font-size: 11px; overflow-wrap: anywhere; }
.projects, .about { padding: 20px 0; border-top: 1px solid var(--line); }
.projects > div { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 10px; }
.projects article { display: grid; grid-template-columns: auto 1fr auto; align-items: center; gap: 10px; padding: 9px 11px; background: #f1f5f4; border: 1px solid var(--line); border-radius: 12px; font-size: 13px; }
.projects span, .about p, .empty-state { color: var(--muted); }
.projects small { color: var(--accent); font-weight: 700; }
.about { padding-bottom: 34px; }
.about p { max-width: 750px; font-size: 14px; }
.empty-state { padding: 19px 0; }
.site-footer { padding: 19px 0; color: var(--muted); background: #eaf0ee; font-size: 13px; }
.site-footer a { color: var(--accent); }
.skip-link { position: absolute; top: 10px; left: -999px; z-index: 20; padding: 8px 12px; color: #fff; background: var(--ink); }
.skip-link:focus { left: 10px; }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0, 0, 0, 0); }
[hidden] { display: none !important; }

@media (max-width: 1150px) { .cards { grid-template-columns: repeat(3, minmax(0, 1fr)); } }
@media (max-width: 860px) { .cards { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
@media (max-width: 640px) {
  :root { --toolbar-offset: 136px; }
  .shell { width: min(100% - 28px, 1180px); }
  .site-header .shell { height: 54px; gap: 11px; }
  .brand-cn { font-size: 19px; }
  .brand-en { font-size: 11px; }
  .site-header p { font-size: 11px; }
  .intro { padding: 23px 0 13px; }
  .intro h1 { font-size: 32px; }
  .lede { font-size: 15px; }
  .directory-toolbar { margin: 0 -7px; padding: 8px 7px; }
  .search input { padding: 11px 0; }
  .clear-search { padding: 9px 10px; font-size: 12px; }
  .category-row { display: block; margin-top: 7px; }
  .category-nav { margin-right: -7px; padding: 0 7px 2px 1px; }
  .search-result { margin-top: 5px; }
  .category-heading { display: block; }
  .category-heading p { margin-top: 2px; }
  .cards { grid-template-columns: 1fr; }
  .projects article { grid-template-columns: 1fr; gap: 2px; width: 100%; }
  kbd { display: none; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .card { transition: none; }
  .card:hover { transform: none; }
}