:root {
  --bg: #0f1220;
  --bg-soft: #161a2c;
  --panel: #1b2036;
  --card: #222845;
  --card-hover: #2a3156;
  --border: #2e3554;
  --text: #eef1fb;
  --text-dim: #a6aed0;
  --accent: #6c8cff;
  --accent-2: #ff7a59;
  --cn: #ff5252;
  --us: #4d8dff;
  --oss: #37d0a3;
  --skills: #b06bff;
  --radius: 14px;
  --shadow: 0 6px 20px rgba(0, 0, 0, .28);
}

* { box-sizing: border-box; }

html, body { margin: 0; padding: 0; }

body {
  font-family: "Segoe UI", "PingFang SC", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  background:
    radial-gradient(1000px 400px at 80% -10%, rgba(108, 140, 255, .18), transparent 60%),
    radial-gradient(800px 400px at 10% -10%, rgba(255, 122, 89, .12), transparent 60%),
    var(--bg);
  color: var(--text);
  min-height: 100vh;
}

/* ---------- header ---------- */
.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
  padding: 20px clamp(16px, 4vw, 40px);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 10;
  backdrop-filter: blur(10px);
  background: rgba(15, 18, 32, .82);
}

.brand { display: flex; align-items: center; gap: 14px; }

.brand-mark {
  display: block;
  flex: 0 0 auto;
  width: 44px; height: 44px;
  border-radius: 12px;
}

.footer-brand .brand-mark { width: 36px; height: 36px; border-radius: 10px; }

.brand h1 { margin: 0; font-size: 20px; line-height: 1.3; }
.brand h1 [lang="en"] { color: var(--text-dim); font-weight: 600; font-size: 16px; }
#subtitle { margin: 2px 0 0; font-size: 13px; color: var(--text-dim); }

.controls { display: flex; align-items: center; gap: 14px; flex-wrap: wrap; }

.detect-hint {
  font-size: 12px;
  color: var(--text-dim);
  border: 1px dashed var(--border);
  padding: 4px 10px;
  border-radius: 999px;
}

.lang-switch {
  display: flex;
  border: 1px solid var(--border);
  border-radius: 999px;
  overflow: hidden;
  background: var(--bg-soft);
  transition: border-color .15s;
}

.lang-switch:hover { border-color: var(--accent); }

.lang-select {
  appearance: none;
  -webkit-appearance: none;
  border: 0;
  background-color: transparent;
  color: var(--text);
  padding: 8px 30px 8px 14px;
  font-size: 13px;
  font-family: inherit;
  line-height: 1.2;
  cursor: pointer;
  /* Caret is drawn by CSS so it keeps the accent colour in every browser. */
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 10 6'%3E%3Cpath fill='%236c8cff' d='M0 0h10L5 6z'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 12px center;
  background-size: 9px 6px;
}

.lang-select:focus-visible { outline: 2px solid var(--accent); outline-offset: -2px; }

.lang-select option { background: var(--bg-soft); color: var(--text); }

/* ---------- layout: left / right / bottom ---------- */
main {
  padding: 24px clamp(16px, 4vw, 40px) 40px;
  display: flex;
  flex-direction: column;
  gap: 24px;
  max-width: 1500px;
  margin: 0 auto;
}

.cols {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}

@media (max-width: 900px) {
  .cols { grid-template-columns: 1fr; }
}

/* ---------- panels ---------- */
.panel {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 18px 18px 20px;
  min-width: 0;
}

#sec-cn { border-top: 3px solid var(--cn); }
#sec-us { border-top: 3px solid var(--us); }
#sec-oss { border-top: 3px solid var(--oss); }
#sec-skills { border-top: 3px solid var(--skills); }

.panel-head {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
  margin-bottom: 14px;
}

.panel-head h2 { margin: 0; font-size: 17px; }

.panel-flag { font-size: 15px; }

.panel-search {
  margin-left: auto;
  width: min(220px, 100%);
  padding: 7px 12px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--bg-soft);
  color: var(--text);
  font-size: 13px;
}

.panel-search:focus-visible { outline: 2px solid var(--accent); outline-offset: 1px; }
.panel-search::placeholder { color: var(--text-dim); }

/* ---------- category chips ---------- */
.chips {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 14px;
}

.chip {
  appearance: none;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--bg-soft);
  color: var(--text-dim);
  font-size: 12px;
  padding: 5px 12px;
  cursor: pointer;
  transition: background .15s, color .15s, border-color .15s;
}

.chip:hover { color: var(--text); border-color: var(--accent); }
.chip:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

.chip.active {
  background: rgba(108, 140, 255, .18);
  border-color: var(--accent);
  color: var(--accent);
  font-weight: 600;
}

/* ---------- cards ---------- */
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(230px, 1fr));
  gap: 12px;
}

.card {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 12px;
  border-radius: 10px;
  background: var(--card);
  border: 1px solid transparent;
  color: var(--text);
  text-decoration: none;
  transition: background .15s, border-color .15s, transform .15s;
}

.card:hover {
  background: var(--card-hover);
  border-color: var(--accent);
  transform: translateY(-2px);
}

.card[hidden] { display: none; }
.card.collapsed-hide { display: none; }

.card:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

.card-icon {
  position: relative;
  flex: 0 0 auto;
  display: grid;
  place-items: center;
  width: 38px; height: 38px;
  border-radius: 9px;
  background: var(--bg-soft);
  font-weight: 700;
  font-size: 16px;
  color: var(--text-dim);
  overflow: hidden;
}

.card-icon img {
  position: absolute;
  inset: 0;
  width: 100%; height: 100%;
  object-fit: contain;
  padding: 6px;
  background: #fff;
  border-radius: 9px;
}

.card-body { display: flex; flex-direction: column; gap: 3px; min-width: 0; }
.card-name {
  font-size: 14px;
  font-weight: 600;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.card-intro {
  font-size: 12px;
  line-height: 1.5;
  color: var(--text-dim);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  min-height: 3em;
}

.card-tag {
  margin-left: auto;
  align-self: flex-start;
  flex: 0 0 auto;
  font-size: 11px;
  color: var(--accent);
  border: 1px solid rgba(108, 140, 255, .35);
  background: rgba(108, 140, 255, .1);
  padding: 2px 8px;
  border-radius: 999px;
  white-space: nowrap;
}

.empty { grid-column: 1 / -1; text-align: center; color: var(--text-dim); font-size: 13px; margin: 8px 0; }

/* ---------- ranking ---------- */
.rank-meta { font-size: 12px; color: var(--text-dim); }

.rank-src {
  margin-left: auto;
  font-size: 12px;
  color: var(--accent);
  text-decoration: none;
}

.rank-src:hover { text-decoration: underline; }

.rank-tabs {
  display: flex;
  gap: 8px;
  margin-bottom: 12px;
}

/* Modality tab row: 11 boards, so it scrolls sideways instead of wrapping. */
.rank-tabs-scroll {
  flex-wrap: nowrap;
  overflow-x: auto;
  overscroll-behavior-x: contain;
  scrollbar-width: none;
  padding-bottom: 4px;
  margin-bottom: 8px;
}
.rank-tabs-scroll::-webkit-scrollbar { display: none; }
.rank-tabs-scroll .rank-tab { flex: 0 0 auto; white-space: nowrap; }

.rank-tab {
  appearance: none;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--bg-soft);
  color: var(--text-dim);
  font-size: 12px;
  padding: 5px 14px;
  cursor: pointer;
  transition: background .15s, color .15s, border-color .15s;
}

.rank-tab:hover { color: var(--text); border-color: var(--accent); }
.rank-tab:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

.rank-tab.active {
  background: rgba(108, 140, 255, .18);
  border-color: var(--accent);
  color: var(--accent);
  font-weight: 600;
}

.rank-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.rank-row {
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr) auto 64px;
  gap: 10px;
  align-items: center;
  padding: 8px 10px;
  border-radius: 8px;
  font-size: 13px;
}

.rank-row[hidden] { display: none; }

.rank-row:nth-child(odd) { background: rgba(255, 255, 255, .03); }

.rank-no { font-weight: 700; color: var(--text-dim); font-variant-numeric: tabular-nums; }
.top1 .rank-no { color: #ffd75e; }
.top2 .rank-no { color: #c9d1e8; }
.top3 .rank-no { color: #e8a06c; }

.rank-name { font-weight: 600; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.rank-org { color: var(--text-dim); font-size: 12px; }
.rank-score { color: var(--accent); font-weight: 600; text-align: right; font-variant-numeric: tabular-nums; }

.rank-more, .grid-more {
  margin-top: 12px;
  width: 100%;
  padding: 9px;
  border-radius: 10px;
  border: 1px solid var(--border);
  background: var(--bg-soft);
  color: var(--text);
  font-size: 13px;
  cursor: pointer;
  transition: border-color .15s, background .15s;
}

.rank-more:hover, .grid-more:hover { border-color: var(--accent); background: var(--card); }
.rank-more:focus-visible, .grid-more:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

@media (max-width: 560px) {
  .rank-row { grid-template-columns: 36px minmax(0, 1fr) 56px; }
  .rank-org { display: none; }
}

/* ---------- footer ---------- */
.site-footer {
  margin-top: 28px;
  border-top: 1px solid var(--border);
  background: var(--bg-soft);
  color: var(--text-dim);
  font-size: 12px;
}

.footer-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 26px 20px 18px;
  display: flex;
  justify-content: space-between;
  gap: 32px;
  flex-wrap: wrap;
}

.footer-brand {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  max-width: 340px;
}

.footer-brand strong { color: var(--text); font-size: 14px; }
.footer-brand p { margin: 4px 0 0; line-height: 1.6; }

.footer-cols {
  display: flex;
  gap: 48px;
  flex-wrap: wrap;
}

.footer-col h3 {
  margin: 0 0 8px;
  font-size: 12px;
  font-weight: 600;
  color: var(--text);
  text-transform: uppercase;
  letter-spacing: .04em;
}

.footer-col ul { list-style: none; margin: 0; padding: 0; }
.footer-col li { margin: 4px 0; }

.footer-col a {
  color: var(--text-dim);
  text-decoration: none;
  transition: color .15s;
}
.footer-col a:hover { color: var(--accent); }

.footer-col p { margin: 0; max-width: 320px; line-height: 1.7; }

.footer-bottom {
  border-top: 1px solid var(--border);
  text-align: center;
  padding: 14px 20px;
}

@media (max-width: 720px) {
  .footer-inner { flex-direction: column; gap: 20px; }
  .footer-cols { gap: 28px; }
}

/* ---------- sticky section nav + global search (2nd header row) ---------- */
html { scroll-behavior: smooth; }

.topnav {
  flex-basis: 100%;
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
  margin-top: 12px;
}

.nav-link {
  padding: 6px 13px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--bg-soft);
  color: var(--text-dim);
  font-size: 13px;
  text-decoration: none;
  white-space: nowrap;
  transition: color .15s, border-color .15s, background .15s;
}
.nav-link:hover { color: var(--text); border-color: var(--accent); }
.nav-link.active { color: #fff; border-color: var(--accent); background: rgba(108, 140, 255, .18); }

.global-search {
  flex: 1 1 200px;
  min-width: 150px;
  padding: 7px 14px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--bg-soft);
  color: var(--text);
  font-size: 13px;
}
.global-search:focus-visible { outline: 2px solid var(--accent); outline-offset: 1px; }
.global-search::placeholder { color: var(--text-dim); }

.global-count { font-size: 12px; color: var(--text-dim); white-space: nowrap; }

.backtop {
  position: fixed;
  right: 22px;
  bottom: 26px;
  z-index: 60;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  border: 1px solid var(--border);
  background: var(--panel);
  color: var(--text);
  font-size: 18px;
  line-height: 1;
  cursor: pointer;
  box-shadow: var(--shadow);
  display: none;
  align-items: center;
  justify-content: center;
}
.backtop.show { display: flex; }

#app section { scroll-margin-top: 150px; }

@media (max-width: 720px) {
  /* On small screens keep only the compact nav row sticky, not the whole header. */
  .site-header { position: static; }
  .topnav {
    position: sticky;
    top: 0;
    z-index: 20;
    flex-wrap: nowrap;
    overflow-x: auto;
    margin: 0 calc(-1 * clamp(16px, 4vw, 40px));
    padding: 8px clamp(16px, 4vw, 40px);
    background: rgba(15, 18, 32, .94);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border);
  }
  .global-search { flex: 0 0 150px; }
  #app section { scroll-margin-top: 64px; }
}