/* sleek buttons */
:root { --r-btn: 4px; --r-chip: 4px; }
/* lang.ugrad.ai · top chrome: update · version · install · AI */
:root {
  --lang-bg: #070a0f;
  --lang-panel: #0e141c;
  --lang-ink: #e8ecf1;
  --lang-mut: #8b93a0;
  --lang-line: #2a3038;
  --lang-acc: #7dd3fc;
  --lang-ok: #4ade80;
  --lang-gold: #c9b896;
  --lang-hot: #f87171;
  --lang-header-h: 52px;
  --lang-sub-h: 40px;
  --mono: ui-monospace, Menlo, monospace;
}
* { box-sizing: border-box; }
html, body {
  margin: 0;
  min-height: 100%;
  background: var(--lang-bg);
  color: var(--lang-ink);
  font: 14px/1.45 system-ui, -apple-system, sans-serif;
}
a { color: var(--lang-acc); text-decoration: none; }
a:hover { text-decoration: underline; }

/* ── sticky top bar ── */
.lang-top {
  position: sticky;
  top: 0;
  z-index: 100;
  background: linear-gradient(180deg, #0a0e14 0%, #0c1118 100%);
  border-bottom: 1px solid var(--lang-line);
  box-shadow: 0 8px 24px rgba(0,0,0,.35);
}
.lang-top-inner {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 14px;
  min-height: var(--lang-header-h);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 12px;
}
.lang-brand {
  display: flex;
  align-items: baseline;
  gap: 8px;
  font-weight: 800;
  letter-spacing: .02em;
  white-space: nowrap;
}
.lang-brand b { color: var(--lang-ink); font-size: 15px; }
.lang-brand span { color: var(--lang-mut); font: 600 11px var(--mono); }
.lang-brand a { color: inherit; text-decoration: none; }
.lang-brand a:hover { color: var(--lang-acc); }

.lang-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
  align-items: center;
  flex: 1;
}
.lang-nav a, .lang-nav button {
  appearance: none;
  border: 1px solid transparent;
  background: transparent;
  color: var(--lang-mut);
  font: 650 11px system-ui;
  padding: 6px 10px;
  border-radius: var(--r-btn);
  cursor: pointer;
  text-decoration: none;
  letter-spacing: .04em;
  text-transform: uppercase;
}
.lang-nav a:hover, .lang-nav button:hover {
  color: var(--lang-ink);
  border-color: var(--lang-line);
  background: rgba(255,255,255,.04);
  text-decoration: none;
}
.lang-nav a.on, .lang-nav a.primary {
  color: #0a0c10;
  background: var(--lang-acc);
  border-color: var(--lang-acc);
}
.lang-nav a.ai {
  color: var(--lang-ok);
  border-color: rgba(74,222,128,.35);
}
.lang-nav a.ai:hover {
  background: rgba(74,222,128,.12);
  color: var(--lang-ok);
}

.lang-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  align-items: center;
  margin-left: auto;
}
.lang-pill {
  font: 600 10px var(--mono);
  color: var(--lang-mut);
  border: 1px solid var(--lang-line);
  border-radius: var(--r-btn);
  padding: 3px 9px;
  white-space: nowrap;
}
.lang-pill.ok { color: var(--lang-ok); border-color: rgba(74,222,128,.4); }
.lang-pill.live { color: var(--lang-acc); border-color: rgba(125,211,252,.4); }
.lang-pill.gold { color: var(--lang-gold); border-color: rgba(201,184,150,.4); }

/* sub-rail: version detail */
.lang-sub {
  border-top: 1px solid rgba(42,48,56,.6);
  background: rgba(0,0,0,.25);
}
.lang-sub-inner {
  max-width: 1100px;
  margin: 0 auto;
  padding: 6px 14px;
  min-height: var(--lang-sub-h);
  display: flex;
  flex-wrap: wrap;
  gap: 8px 14px;
  align-items: center;
  font: 600 11px var(--mono);
  color: var(--lang-mut);
}
.lang-sub a { color: var(--lang-acc); }

/* site body */
.lang-wrap {
  max-width: 1100px;
  margin: 0 auto;
  padding: 20px 14px 64px;
}
.lang-kicker {
  font: 700 11px var(--mono);
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--lang-ok);
  margin: 0 0 8px;
}
.lang-wrap h1 {
  margin: 0 0 8px;
  font: 800 1.65rem/1.2 system-ui;
  letter-spacing: -.02em;
}
.lang-lead {
  color: var(--lang-mut);
  max-width: 46rem;
  margin: 0 0 22px;
  font-size: 14px;
}
.lang-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 12px;
}
.lang-card {
  border: 1px solid var(--lang-line);
  border-radius: 6px;
  background: var(--lang-panel);
  padding: 14px 16px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  min-height: 140px;
}
.lang-card h2 {
  margin: 0;
  font: 700 13px system-ui;
  letter-spacing: .02em;
}
.lang-card p {
  margin: 0;
  flex: 1;
  font-size: 12px;
  color: var(--lang-mut);
  line-height: 1.4;
}
.lang-card .actions { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 4px; }
.lang-btn {
  display: inline-block;
  padding: 6px 12px;
  border-radius: var(--r-btn);
  border: 1px solid var(--lang-line);
  background: #141a22;
  color: var(--lang-ink);
  font: 650 11px system-ui;
  text-decoration: none;
  cursor: pointer;
}
.lang-btn:hover { border-color: var(--lang-acc); color: var(--lang-acc); text-decoration: none; }
.lang-btn.primary {
  background: var(--lang-acc);
  border-color: var(--lang-acc);
  color: #0a0c10;
}
.lang-btn.primary:hover { filter: brightness(1.08); color: #0a0c10; }

.lang-section {
  margin-top: 28px;
}
.lang-section h2 {
  margin: 0 0 10px;
  font: 700 11px system-ui;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--lang-mut);
}
.lang-pre {
  background: #0a0c10;
  border: 1px solid var(--lang-line);
  border-radius: 12px;
  padding: 12px 14px;
  overflow: auto;
  font: 600 11px/1.45 var(--mono);
  color: var(--lang-mut);
  margin: 0;
}
.lang-foot {
  margin-top: 36px;
  padding-top: 16px;
  border-top: 1px solid var(--lang-line);
  font: 600 11px var(--mono);
  color: var(--lang-mut);
}

/* panels for update/install */
.lang-panel {
  border: 1px solid var(--lang-line);
  border-radius: 6px;
  background: var(--lang-panel);
  padding: 16px 18px;
  margin: 12px 0;
}
.lang-panel h3 {
  margin: 0 0 8px;
  font: 700 14px system-ui;
}
.lang-panel ul { margin: 8px 0 0; padding-left: 1.2rem; color: var(--lang-mut); }
.lang-panel li { margin: 4px 0; }

@media (max-width: 640px) {
  .lang-meta { width: 100%; }
  .lang-nav a, .lang-nav button { padding: 5px 8px; font-size: 10px; }
}