/* Shared shell for 果蠅神諭: tokens + top navigation. Pages keep their own layout CSS. */
:root {
  --bg: #04050a;
  --bg-2: #070a12;
  --ink: #e8ecf6;
  --dim: #8b93a8;
  --muted: #4a5266;
  --cyan: #5ce1ff;
  --cyan-soft: rgba(92, 225, 255, 0.10);
  --cyan-line: rgba(92, 225, 255, 0.35);
  --warm: #ffb86b;
  --line: rgba(255, 255, 255, 0.08);
  --line-2: rgba(255, 255, 255, 0.14);
  --panel: rgba(8, 10, 16, 0.72);
  --panel-solid: #0a0d15;
  --sans: "Noto Sans TC", "PingFang TC", "Microsoft JhengHei", system-ui, sans-serif;
  --mono: "IBM Plex Mono", ui-monospace, "SF Mono", Menlo, monospace;
}

.site-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 30;
  height: 56px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding-inline: 16px;
  pointer-events: none;
}
.site-nav > * { pointer-events: auto; }
.site-nav.solid {
  background: linear-gradient(180deg, rgba(4, 5, 10, 0.96), rgba(4, 5, 10, 0.82));
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(12px);
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--ink);
  text-decoration: none;
  font: 500 14px/1 var(--sans);
  letter-spacing: 0.14em;
  white-space: nowrap;
}
.brand i {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 14px rgba(92, 225, 255, 0.85);
}
.brand small {
  font: 400 10.5px/1 var(--mono);
  letter-spacing: 0.04em;
  color: var(--muted);
}
.tabs-nav {
  display: flex;
  gap: 2px;
  padding: 4px;
  border-radius: 999px;
  background: var(--panel);
  border: 1px solid var(--line);
  backdrop-filter: blur(12px);
}
.tabs-nav a {
  color: var(--dim);
  text-decoration: none;
  font: 400 13px/1 var(--sans);
  letter-spacing: 0.12em;
  padding: 8px 14px;
  border-radius: 999px;
  white-space: nowrap;
}
.tabs-nav a:hover { color: var(--ink); }
.tabs-nav a[aria-current="page"] { color: var(--cyan); background: var(--cyan-soft); }
.tabs-nav a:focus-visible, .brand:focus-visible { outline: 2px solid var(--cyan); outline-offset: 2px; }

@media (max-width: 560px) {
  .brand small { display: none; }
  .tabs-nav a { padding: 8px 10px; letter-spacing: 0.06em; }
}