/* Ravn Edition — design tokens
   Dark-first, OKLCH, restrained palette with a single warm accent.
   Brand register: typography-led, generous whitespace, high contrast. */

:root {
  --bg:        oklch(0.13  0.005 270);
  --bg-elev:   oklch(0.16  0.006 270);
  --fg:        oklch(0.97  0.005  80);
  --muted:     oklch(0.66  0.012 270);
  --subtle:    oklch(0.42  0.010 270);
  --border:    oklch(0.26  0.010 270);
  --border-strong: oklch(0.40 0.010 270);
  --accent:    oklch(0.82  0.155 65);
  --accent-fg: oklch(0.14  0.020 65);
  --code-bg:   oklch(0.18  0.008 270);
  --max:       980px;
  --max-prose: 70ch;
  --radius:    10px;
  --radius-lg: 14px;
  --shadow:    0 1px 0 oklch(1 0 0 / .04), 0 8px 32px -12px oklch(0 0 0 / .6);
  --ease:      cubic-bezier(.2, .8, .2, 1);
  color-scheme: dark;
}

:root[data-theme="light"] {
  --bg:        oklch(0.99  0.003  80);
  --bg-elev:   oklch(0.97  0.004  80);
  --fg:        oklch(0.17  0.008 270);
  --muted:     oklch(0.46  0.010 270);
  --subtle:    oklch(0.62  0.008 270);
  --border:    oklch(0.91  0.005 270);
  --border-strong: oklch(0.78 0.008 270);
  --accent:    oklch(0.55  0.180 50);
  --accent-fg: oklch(0.99  0.003  80);
  --code-bg:   oklch(0.96  0.005 270);
  --shadow:    0 1px 0 oklch(0 0 0 / .03), 0 4px 24px -10px oklch(0 0 0 / .12);
  color-scheme: light;
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
html { -webkit-text-size-adjust: 100%; }

body {
  font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, system-ui, sans-serif;
  font-feature-settings: "ss01", "cv11", "calt";
  font-synthesis: none;
  background: var(--bg);
  color: var(--fg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

::selection { background: var(--accent); color: var(--accent-fg); }

a {
  color: var(--fg);
  text-decoration: none;
  border-bottom: 1px solid var(--border-strong);
  transition: color .15s var(--ease), border-color .15s var(--ease);
}
a:hover { color: var(--accent); border-bottom-color: var(--accent); }
a:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 2px;
}

/* offset anchor scrolling so headings clear the sticky topbar.
   --topbar-h is set from JS to match the live topbar height (it can wrap on narrow screens). */
html { scroll-padding-top: calc(var(--topbar-h, 64px) + 16px); }

/* ---------- topbar ---------- */
.topbar {
  position: sticky; top: 0; z-index: 10;
  display: flex; align-items: center; justify-content: space-between;
  padding: 14px 32px;
  background: color-mix(in oklch, var(--bg) 88%, transparent);
  backdrop-filter: saturate(140%) blur(10px);
  -webkit-backdrop-filter: saturate(140%) blur(10px);
  border-bottom: 1px solid var(--border);
}
.brand {
  display: inline-flex; align-items: baseline; gap: 14px;
  color: var(--fg);
  border-bottom: 0;
  font-weight: 600;
  letter-spacing: -0.01em;
}
.brand:hover { color: var(--accent); }
.brand img {
  height: 22px; width: auto;
  color: var(--fg);
  transition: color .15s var(--ease);
}
.brand:hover img { color: var(--accent); }
.brand span {
  font-size: 13px;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.14em;
}
.brand span em {
  font-style: normal;
  color: var(--subtle);
}

.topbar-actions { display: flex; align-items: center; gap: 10px; }
.search-filter {
  display: flex;
  gap: 6px;
  padding: 12px 16px 0;
}
.search-lang {
  background: var(--bg-elev);
  border: 1px solid var(--border);
  color: var(--muted);
  padding: 5px 12px;
  border-radius: 999px;
  font-size: 11px; font-weight: 600;
  letter-spacing: 0.08em;
  cursor: pointer;
  transition: color .15s var(--ease), background .15s var(--ease);
}
.search-lang:hover { color: var(--fg); }
.search-lang.active { background: var(--fg); color: var(--bg); border-color: var(--fg); }

.icon-btn {
  background: var(--bg-elev);
  border: 1px solid var(--border);
  width: 34px; height: 34px;
  border-radius: 999px;
  cursor: pointer;
  font-size: 14px;
  color: var(--muted);
  display: inline-flex; align-items: center; justify-content: center;
  transition: color .15s var(--ease), border-color .15s var(--ease);
}
.icon-btn:hover { color: var(--fg); border-color: var(--border-strong); }

/* ---------- landing ---------- */
.landing {
  max-width: var(--max);
  margin: 0 auto;
  padding: clamp(64px, 12vw, 128px) 32px 96px;
}

.hero {
  display: grid;
  gap: 28px;
  padding-bottom: 72px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 64px;
}
.hero .eyebrow {
  font-size: 12px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--muted);
  margin: 0;
  display: inline-flex; align-items: center; gap: 10px;
}
.hero .eyebrow::before {
  content: "";
  width: 28px; height: 1px;
  background: var(--accent);
}
.hero h1 {
  font-size: clamp(2.4rem, 5.5vw, 4.2rem);
  line-height: 1.02;
  letter-spacing: -0.035em;
  font-weight: 700;
  margin: 0;
  max-width: 18ch;
}
.hero h1 .accent { color: var(--accent); }
.hero .lede {
  color: var(--muted);
  margin: 0;
  font-size: clamp(1.05rem, 1.6vw, 1.25rem);
  line-height: 1.5;
  max-width: 56ch;
}

.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1px;
  background: var(--border);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
}
.card {
  background: var(--bg);
  padding: 32px 28px;
  display: grid;
  align-content: start;
  gap: 18px;
  transition: background .2s var(--ease);
}
.card:hover { background: var(--bg-elev); }
.card h2 {
  margin: 0;
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--muted);
}
.card .lang-name {
  font-size: 1.85rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1;
  color: var(--fg);
}
.card ul { list-style: none; padding: 0; margin: 0; display: grid; gap: 2px; }
.card li { margin: 0; }
.card li a {
  display: flex; align-items: center; justify-content: space-between;
  gap: 12px;
  padding: 10px 0;
  border-bottom: 1px solid var(--border);
  color: var(--fg);
  font-size: 0.95rem;
}
.card li:last-child a { border-bottom: 0; }
.card li a::after {
  content: "→";
  color: var(--subtle);
  transition: transform .2s var(--ease), color .15s var(--ease);
}
.card li a:hover { color: var(--accent); }
.card li a:hover::after { color: var(--accent); transform: translateX(4px); }

.site-footer {
  max-width: var(--max);
  margin: 0 auto;
  padding: 28px 32px 36px;
  border-top: 1px solid var(--border);
  color: var(--subtle);
  font-size: 0.85rem;
  display: flex; flex-wrap: wrap; gap: 8px 24px;
  justify-content: space-between; align-items: center;
}
.site-footer p { margin: 0; }
.site-footer a { color: var(--muted); border-bottom-color: var(--border); }
.site-footer a:hover { color: var(--accent); border-bottom-color: var(--accent); }

/* ---------- guide content ---------- */
.guide {
  max-width: var(--max-prose);
  margin: 0 auto;
  padding: 64px 32px 120px;
  font-size: 1.02rem;
}
.guide h1, .guide h2, .guide h3, .guide h4 {
  line-height: 1.2;
  letter-spacing: -0.02em;
  font-weight: 700;
}
.guide h1 { font-size: 2.4rem; margin-top: 0; margin-bottom: 1rem; }
.guide h2 { font-size: 1.7rem; margin-top: 3rem; padding-top: 1.5rem; border-top: 1px solid var(--border); }
.guide h3 { font-size: 1.25rem; margin-top: 2rem; }
.guide h4 { font-size: 1.05rem; margin-top: 1.6rem; color: var(--muted); }
.guide p { margin: 1em 0; }
.guide a { color: var(--accent); border-bottom-color: color-mix(in oklch, var(--accent) 40%, transparent); }
.guide a:hover { border-bottom-color: var(--accent); }
.guide ul, .guide ol { padding-left: 1.4em; }
.guide li { margin: 0.4em 0; }
.guide pre {
  background: var(--code-bg);
  padding: 18px 20px;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  overflow-x: auto;
  font-size: 0.88em;
  line-height: 1.55;
  font-family: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, monospace;
}
.guide code {
  background: var(--code-bg);
  padding: 2px 6px;
  border-radius: 4px;
  font-size: 0.88em;
  font-family: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, monospace;
  color: var(--fg);
}
.guide pre code { background: transparent; padding: 0; border: 0; }
.guide blockquote {
  margin: 1.5em 0;
  padding: 0.6em 0 0.6em 1.25em;
  border-left: 2px solid var(--accent);
  color: var(--muted);
  font-style: italic;
}
.guide blockquote p { margin: 0.4em 0; }
.guide table {
  border-collapse: collapse;
  margin: 1.5em 0;
  width: 100%;
  font-size: 0.95em;
}
.guide th, .guide td {
  border-bottom: 1px solid var(--border);
  padding: 10px 14px;
  text-align: left;
}
.guide th { font-weight: 600; color: var(--muted); font-size: 0.82em; letter-spacing: 0.06em; text-transform: uppercase; }
.guide hr { border: 0; border-top: 1px solid var(--border); margin: 3rem 0; }
.guide img { max-width: 100%; border-radius: var(--radius); }

/* ---------- placeholder pages ---------- */
.placeholder {
  max-width: var(--max-prose);
  margin: 0 auto;
  padding: 120px 32px;
  text-align: center;
  color: var(--muted);
}
.placeholder h1 {
  font-size: 2rem;
  letter-spacing: -0.025em;
  color: var(--fg);
  margin-bottom: 1rem;
}

/* ---------- search ---------- */
#search-dialog {
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-lg);
  padding: 0;
  background: var(--bg-elev);
  color: var(--fg);
  width: min(640px, 92vw);
  box-shadow: var(--shadow);
}
#search-dialog::backdrop {
  background: oklch(0 0 0 / .55);
  backdrop-filter: blur(4px);
}
#search-input {
  width: 100%;
  padding: 18px 20px;
  border: 0;
  border-bottom: 1px solid var(--border);
  background: transparent;
  color: var(--fg);
  font-size: 1.05rem;
  outline: none;
  font-family: inherit;
}
#search-input::placeholder { color: var(--subtle); }
#search-results { list-style: none; margin: 0; padding: 8px; max-height: 56vh; overflow-y: auto; }
#search-results li { padding: 0; }
#search-results a {
  display: block;
  padding: 10px 14px;
  color: var(--fg);
  border: 0;
  border-radius: var(--radius);
  font-size: 0.95rem;
}
#search-results a:hover { background: var(--bg); color: var(--accent); }
#search-results .lang-tag {
  display: inline-block;
  font-size: 10px;
  letter-spacing: 0.12em;
  color: var(--muted);
  margin-right: 10px;
  text-transform: uppercase;
  font-weight: 600;
}

/* ---------- responsive ---------- */
@media (max-width: 720px) {
  .topbar { padding: 12px 18px; flex-wrap: wrap; gap: 10px; }
  .brand span { display: none; }
  .landing { padding: 48px 20px 64px; }
  .hero { padding-bottom: 48px; margin-bottom: 40px; }
  .guide { padding: 40px 20px 80px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}