:root {
  --bg: #ffffff;
  --fg: #1a1a1a;
  --muted: #666666;
  --faint: #999999;
  --line: #e2e2e2;
  --surface: #f7f7f5;
  --accent: #b45309;
  --accent-bright: #d97706;
  --code-bg: #f4f2ee;
  --max: 780px;
  font-synthesis: none;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #131211;
    --fg: #f0ede8;
    --muted: #a8a29e;
    --faint: #78716c;
    --line: #2e2b28;
    --surface: #1c1a18;
    --accent: #f0a05a;
    --accent-bright: #f5b878;
    --code-bg: #201d1a;
  }
}

* {
  box-sizing: border-box;
}

html {
  color-scheme: light dark;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
  line-height: 1.65;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--accent);
  text-decoration: none;
}
a:hover {
  text-decoration: underline;
}

code, pre, kbd, .mono {
  font-family: "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
  font-size: 0.92em;
}

code {
  background: var(--code-bg);
  padding: 0.12em 0.4em;
  border-radius: 4px;
}

pre {
  background: var(--code-bg);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 16px 18px;
  overflow-x: auto;
  line-height: 1.55;
}
pre code {
  background: none;
  padding: 0;
}

h1, h2, h3, h4 {
  line-height: 1.25;
  font-weight: 650;
  letter-spacing: -0.01em;
}

h1 { font-size: 2.1rem; margin: 0 0 0.3em; }
h2 { font-size: 1.4rem; margin: 2.2em 0 0.6em; padding-top: 0.4em; border-top: 1px solid var(--line); }
h3 { font-size: 1.1rem; margin: 1.6em 0 0.5em; }

p { margin: 0.9em 0; }
ul, ol { padding-left: 1.3em; }
li { margin: 0.35em 0; }

table {
  border-collapse: collapse;
  width: 100%;
  margin: 1em 0;
  font-size: 0.92rem;
}
th, td {
  text-align: left;
  padding: 6px 12px 6px 0;
  border-bottom: 1px solid var(--line);
}
th { color: var(--muted); font-weight: 600; }

/* Top nav */
.site-header {
  border-bottom: 1px solid var(--line);
  position: sticky;
  top: 0;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(10px);
  z-index: 10;
}
.site-header .row {
  max-width: 980px;
  margin: 0 auto;
  padding: 14px 24px;
  display: flex;
  align-items: center;
  gap: 28px;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  font-weight: 700;
  font-size: 1.15rem;
  letter-spacing: -0.01em;
  color: var(--fg) !important;
  text-decoration: none !important;
}
.brand-icon {
  height: 30px;
  width: 30px;
  display: block;
}
.brand-text { white-space: nowrap; }
.dot { color: var(--accent); }
.site-nav {
  display: flex;
  gap: 4px;
  margin-left: auto;
  font-size: 0.92rem;
}
.site-nav a {
  color: var(--muted);
  padding: 6px 10px;
  border-radius: 6px;
}
.site-nav a:hover, .site-nav a.active {
  color: var(--fg);
  background: var(--surface);
  text-decoration: none;
}

.badge {
  display: inline-block;
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.03em;
  text-transform: uppercase;
  color: var(--accent);
  background: color-mix(in srgb, var(--accent) 12%, transparent);
  padding: 3px 9px;
  border-radius: 999px;
}

.container {
  max-width: var(--max);
  margin: 0 auto;
  padding: 56px 24px 90px;
}
.container.wide { max-width: 1080px; }

.hero {
  text-align: left;
  padding: 64px 0 16px;
}
.hero p.tagline {
  font-size: 1.25rem;
  color: var(--muted);
  max-width: 46ch;
}
.hero .actions {
  display: flex;
  gap: 12px;
  margin-top: 28px;
  flex-wrap: wrap;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 10px 18px;
  border-radius: 8px;
  font-weight: 600;
  font-size: 0.95rem;
  border: 1px solid var(--line);
  text-decoration: none !important;
}
.btn.primary {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff !important;
}
.btn.primary:hover { background: var(--accent-bright); border-color: var(--accent-bright); }
.btn:not(.primary) { color: var(--fg) !important; }
.btn:not(.primary):hover { background: var(--surface); }

.principles {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
  margin: 48px 0;
}
.principles div h3 { margin-top: 0; font-size: 1rem; }
.principles div p { color: var(--muted); font-size: 0.94rem; margin: 0.4em 0 0; }

@media (max-width: 720px) {
  .principles { grid-template-columns: 1fr; }
  .spec-layout { grid-template-columns: minmax(0, 1fr) !important; }
  .spec-toc { display: none !important; }

  .site-header .row { padding: 12px 16px; gap: 12px; }
  .brand { font-size: 1.05rem; gap: 7px; }
  .brand-icon { height: 26px; width: 26px; }
  .site-nav { gap: 2px; font-size: 0.86rem; }
  .site-nav a { padding: 6px 8px; }

  .container { padding: 40px 18px 64px; }
  .hero { padding: 32px 0 8px; }
  h1 { font-size: 1.7rem; }
  h2 { font-size: 1.25rem; }
  .hero p.tagline { font-size: 1.1rem; }

  .footer-inner { flex-direction: column; gap: 18px; }
  .footer-bottom { flex-direction: column; gap: 6px; padding-bottom: 32px; }
}

@media (max-width: 380px) {
  .brand-icon { height: 24px; width: 24px; }
  .brand { font-size: 1rem; }
  .site-nav a { padding: 6px 6px; }
}

/* Spec page layout */
.spec-layout {
  display: grid;
  grid-template-columns: 200px minmax(0, 1fr);
  gap: 48px;
  align-items: start;
}
.spec-toc {
  position: sticky;
  top: 76px;
  font-size: 0.86rem;
}
.spec-toc a {
  display: block;
  color: var(--muted);
  padding: 3px 0;
}
.spec-toc a:hover { color: var(--fg); }
.spec-toc .toc-h2 { margin-top: 10px; font-weight: 600; color: var(--fg); }

.note {
  background: var(--surface);
  border: 1px solid var(--line);
  border-left: 3px solid var(--accent);
  border-radius: 6px;
  padding: 12px 16px;
  font-size: 0.92rem;
  margin: 1.2em 0;
}
.note strong { color: var(--accent); }

.token-table code { white-space: nowrap; }

footer.site-footer {
  border-top: 1px solid var(--line);
  background: var(--surface);
  margin-top: 72px;
}
.footer-inner,
.footer-bottom {
  max-width: var(--max);
  margin: 0 auto;
  padding-left: 24px;
  padding-right: 24px;
}
.footer-inner {
  display: flex;
  justify-content: space-between;
  gap: 32px;
  flex-wrap: wrap;
  padding-top: 36px;
  padding-bottom: 28px;
}
.footer-brand .footer-name {
  font-weight: 700;
  font-size: 1.05rem;
  color: var(--fg);
}
.footer-brand p {
  color: var(--muted);
  font-size: 0.88rem;
  margin: 6px 0 0;
  max-width: 42ch;
}
.footer-nav {
  display: flex;
  flex-direction: column;
  gap: 8px;
  font-size: 0.9rem;
}
.footer-nav a { color: var(--muted); }
.footer-nav a:hover { color: var(--fg); }
.footer-bottom {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
  border-top: 1px solid var(--line);
  padding-top: 18px;
  padding-bottom: 40px;
  color: var(--faint);
  font-size: 0.82rem;
}
.footer-bottom .mono { color: var(--faint); }

/* Playground */
.pg-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  align-items: start;
}
@media (max-width: 860px) {
  .pg-grid { grid-template-columns: 1fr; }
}
.pg-grid textarea {
  width: 100%;
  height: 560px;
  font-family: "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
  font-size: 13px;
  line-height: 1.6;
  padding: 14px;
  border-radius: 8px;
  border: 1px solid var(--line);
  background: var(--code-bg);
  color: var(--fg);
  resize: vertical;
}
.pg-output {
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 4px 18px 18px;
  background: var(--surface);
  max-height: 560px;
  overflow-y: auto;
}
.pg-section-title {
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--muted);
  margin: 18px 0 6px;
}
.pg-entry {
  padding: 8px 0;
  border-bottom: 1px solid var(--line);
  font-size: 0.9rem;
}
.pg-entry:last-child { border-bottom: none; }
.pg-entry .t { font-weight: 600; }
.pg-chips { display: flex; gap: 6px; flex-wrap: wrap; margin-top: 4px; }
.pg-chip {
  font-size: 0.72rem;
  padding: 2px 8px;
  border-radius: 999px;
  background: var(--code-bg);
  color: var(--muted);
  border: 1px solid var(--line);
}
.pg-chip.fav { color: var(--accent); border-color: color-mix(in srgb, var(--accent) 40%, transparent); }
.pg-chip.st { font-weight: 700; text-transform: uppercase; letter-spacing: 0.04em; }
.pg-chip.st-unwatched { color: var(--accent); border-color: color-mix(in srgb, var(--accent) 45%, transparent); }
.pg-chip.st-watching { color: #1d5fbf; border-color: color-mix(in srgb, #1d5fbf 45%, transparent); }
.pg-chip.st-watched { color: #2f6f4f; border-color: color-mix(in srgb, #2f6f4f 45%, transparent); }
.pg-chip.st-archived { color: var(--faint); }
@media (prefers-color-scheme: dark) {
  .pg-chip.st-watching { color: #7db2f5; }
  .pg-chip.st-watched { color: #6fbf94; }
}
.pg-warnings { margin: 14px 0 0; padding-left: 1.2em; font-size: 0.85rem; }
.pg-warnings li { color: var(--warn, #9a6700); margin: 4px 0; }
.pg-warnings .ln { font-family: var(--mono, ui-monospace, monospace); color: var(--faint); margin-right: 6px; }
.pg-counts { color: var(--muted); font-size: 0.85rem; margin: 4px 0 10px; }
.pg-empty { color: var(--faint); font-size: 0.9rem; padding: 12px 0; }