/*
 * 9router-go project page.
 *
 * The palette is lifted from the dashboard's own tokens (web/src/index.css):
 * warm paper light theme, charcoal dark theme, terracotta brand. Reason: a
 * visitor who opens the docs and then the dashboard should see one product, and
 * a second invented palette would read as a different tool.
 *
 * Terracotta appears exactly three times: the wordmark plate, the focus ring,
 * and link hover. Brand-500 fails 4.5:1 as link text on paper (3.2:1), so links
 * use brand-700 light / brand-300 dark, both above 5.9:1.
 */

:root {
  color-scheme: light;
  --bg: #fdfaf6;
  --bg-alt: #f7f3ee;
  --surface: #ffffff;
  --border: #e5e7eb;
  --border-subtle: #f1f1f3;
  --text: #0a0a0a;
  --text-muted: #6b7280;
  --link: #a64027;
  --link-hover: #7a2f1d;
  --brand: #e56a4a;
  --radius: 10px;
  --radius-lg: 14px;
  --font-body: Inter, -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}

@media (prefers-color-scheme: dark) {
  :root {
    color-scheme: dark;
    --bg: #1a1a1a;
    --bg-alt: #1f1f1e;
    --surface: #262626;
    --border: #333333;
    --border-subtle: #2a2a2a;
    --text: #ededed;
    --text-muted: #9ca3af;
    --link: #ee8d6a;
    --link-hover: #f4b59c;
  }
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  /* The sticky masthead must not cover the heading an anchor link targets. */
  scroll-padding-top: 5.5rem;
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--link);
  text-decoration-thickness: 1px;
  text-underline-offset: 2px;
}

a:hover {
  color: var(--link-hover);
  text-decoration-thickness: 2px;
}

:focus-visible {
  outline: 2px solid var(--brand);
  outline-offset: 2px;
  border-radius: 4px;
}

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  padding: 0.6rem 1rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  z-index: 10;
}

.skip-link:focus {
  left: 1rem;
  top: 1rem;
}

/* Masthead: flat, with a hairline instead of a shadow. The page scrolls under
   it constantly, so elevation would be noise on every screen. */
.masthead {
  position: sticky;
  top: 0;
  background: var(--bg);
  border-bottom: 1px solid var(--border);
}

.masthead-inner {
  max-width: 52rem;
  margin: 0 auto;
  padding: 0.85rem 1.25rem;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem 1.5rem;
}

.wordmark {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  color: var(--text);
  font-weight: 600;
  text-decoration: none;
  letter-spacing: -0.01em;
}

.wordmark-mark {
  display: grid;
  place-items: center;
  width: 1.75rem;
  height: 1.75rem;
  border-radius: 7px;
  background: var(--brand);
  color: #ffffff;
  font-weight: 700;
  font-size: 1rem;
}

.masthead nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem 1.15rem;
  font-size: 0.9375rem;
}

.masthead nav a {
  color: var(--text-muted);
  text-decoration: none;
  /* 44px tall target without a 44px tall bar. */
  padding: 0.6rem 0;
  display: inline-block;
}

.masthead nav a:hover {
  color: var(--link);
  text-decoration: underline;
  text-decoration-thickness: 2px;
}

.prose {
  max-width: 52rem;
  margin: 0 auto;
  padding: 2.5rem 1.25rem 1rem;
}

.prose > div[align="center"] {
  text-align: center;
}

.prose > div[align="center"] img {
  margin: 0.4rem 0.2rem;
  vertical-align: middle;
}

h1,
h2,
h3,
h4 {
  line-height: 1.25;
  letter-spacing: -0.015em;
  margin: 2.4rem 0 0.9rem;
  scroll-margin-top: 5.5rem;
}

.prose > div[align="center"] h1 {
  margin-top: 0;
  font-size: clamp(1.75rem, 5vw, 2.4rem);
}

h2 {
  font-size: 1.5rem;
  padding-top: 1.4rem;
  border-top: 1px solid var(--border-subtle);
}

h3 {
  font-size: 1.2rem;
}

h4 {
  font-size: 1.05rem;
}

.prose p,
.prose li {
  color: var(--text);
  /* Long env-var lines such as ANTHROPIC_BASE_URL are one unbreakable token.
     Without this they push the page wider than a 360px viewport (R-03). */
  overflow-wrap: break-word;
}

.prose ul,
.prose ol {
  padding-left: 1.4rem;
}

.prose li + li {
  margin-top: 0.3rem;
}

.prose li::marker {
  color: var(--text-muted);
}

.prose hr {
  border: 0;
  border-top: 1px solid var(--border);
  margin: 2rem 0;
}

.prose img {
  max-width: 100%;
  height: auto;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  background: var(--surface);
}

.prose blockquote {
  margin: 1.25rem 0;
  padding: 0.85rem 1.1rem;
  border-left: 3px solid var(--brand);
  background: var(--bg-alt);
  border-radius: 0 var(--radius) var(--radius) 0;
  color: var(--text-muted);
}

.prose blockquote p {
  color: var(--text-muted);
}

.prose code {
  font-family: var(--font-mono);
  font-size: 0.875em;
  background: var(--bg-alt);
  border: 1px solid var(--border-subtle);
  border-radius: 6px;
  padding: 0.12em 0.38em;
}

.prose pre {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1rem 1.1rem;
  overflow-x: auto;
  line-height: 1.55;
}

.prose pre code {
  background: none;
  border: 0;
  padding: 0;
  font-size: 0.8125rem;
}

.prose table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.25rem 0;
  font-size: 0.9375rem;
  display: block;
  overflow-x: auto;
}

.prose th,
.prose td {
  border: 1px solid var(--border);
  padding: 0.55rem 0.75rem;
  text-align: left;
  vertical-align: top;
}

.prose th {
  background: var(--bg-alt);
  font-weight: 600;
}

.prose details {
  margin: 1.25rem 0;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  padding: 0.85rem 1.1rem;
}

.prose summary {
  cursor: pointer;
  font-weight: 600;
  padding: 0.2rem 0;
}

.prose summary:focus-visible {
  outline: 2px solid var(--brand);
  outline-offset: 2px;
}

.colophon {
  max-width: 52rem;
  margin: 0 auto;
  padding: 2rem 1.25rem 3.5rem;
  border-top: 1px solid var(--border);
  color: var(--text-muted);
  font-size: 0.875rem;
}

.colophon code {
  font-family: var(--font-mono);
  font-size: 0.9em;
}