/* gate.css — presentation for t-crypt.github.io/GATE
   Part of a cohesive project-docs family (Aphotic / Gate / …).
   Dark neutral base, mono-forward chrome, hairline borders, accent-driven
   highlighting. The accent is user-selectable and persisted: [data-accent]
   on <html> swaps the --accent variable and everything derived from it. */

:root {
  --bg: #08090b;
  --surface: #0d0f12;
  --fg: #e8e8e8;
  --muted: #8b8e98;
  --dim: #5a606a;
  --border: #202228;
  --border-strong: #2c2f35;
  --accent: #d9a657;
  --accent-soft: rgba(217, 166, 87, 0.14);
  --max: 1200px;
  --rail: 210px;
  --mono: ui-monospace, "Cascadia Code", "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;
  --sans: system-ui, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  color-scheme: dark;
}

[data-accent="signal"]  { --accent: #66d9ff; --accent-soft: rgba(102, 217, 255, 0.14); }
[data-accent="violet"]  { --accent: #b69cff; --accent-soft: rgba(182, 156, 255, 0.14); }
[data-accent="safety"]  { --accent: #5cb98a; --accent-soft: rgba(92, 185, 138, 0.14); }

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  background-image: linear-gradient(90deg, transparent 0, rgba(255, 255, 255, 0.015) 50%, transparent 100%);
}

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

a { color: inherit; }

a:focus-visible, button:focus-visible {
  outline: 1px solid var(--accent);
  outline-offset: 3px;
}

.skip-link {
  position: absolute;
  left: 12px;
  top: -50px;
  background: var(--fg);
  color: var(--bg);
  padding: 8px 12px;
  z-index: 20;
}
.skip-link:focus { top: 12px; }

/* ---------- header ---------- */

.site-header { border-bottom: 1px solid var(--border); }

.header-inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 28px;
  height: 64px;
  display: flex;
  align-items: center;
  gap: 22px;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.08em;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  font-weight: 700;
  color: var(--fg);
}

.gate-mark {
  display: inline-block;
  width: 14px;
  height: 14px;
  border: 1.5px solid var(--accent);
  position: relative;
  background: var(--accent-soft);
}
.gate-mark::after {
  content: "";
  position: absolute;
  left: 5px;
  top: 2.5px;
  width: 1.5px;
  height: 7px;
  background: var(--accent);
}

.gate-mark.mini {
  display: inline-block;
  vertical-align: -2px;
  width: 9px;
  height: 9px;
  margin-right: 7px;
}
.gate-mark.mini::after { left: 3px; top: 1.5px; height: 4.5px; }

.nav-main {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 2px;
}

.site-header nav a,
.accent-toggle,
.menu-toggle {
  border: 0;
  background: none;
  color: var(--muted);
  font: inherit;
  text-decoration: none;
  cursor: pointer;
  padding: 6px 10px;
  letter-spacing: 0.08em;
}

.site-header nav a:hover,
.site-header nav a.on,
.accent-toggle:hover {
  color: var(--accent);
}

.site-header nav a.on { font-weight: 700; }

.menu-toggle { display: none; }

/* ---------- shell / rail ---------- */

.docs-shell {
  max-width: var(--max);
  margin: 0 auto;
  padding: 48px 28px 88px;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 64px;
}

body.docs .docs-shell {
  grid-template-columns: var(--rail) minmax(0, 760px);
  gap: 72px;
  padding-top: 60px;
}

.home .docs-shell { padding-top: 40px; }

.docs-rail { display: block; }

.eyebrow {
  font: 12px var(--mono);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--muted);
  margin: 0;
}

.rail-eyebrow { margin-bottom: 18px; }

.rail-nav { display: flex; flex-direction: column; align-items: flex-start; }

.rail-nav a {
  display: block;
  color: var(--muted);
  text-decoration: none;
  font: 13px/1.6 var(--mono);
  padding: 5px 0;
}

.rail-nav a:hover { color: var(--accent); }

.rail-nav a.on {
  color: var(--fg);
  font-weight: 700;
  box-shadow: inset 2px 0 0 var(--accent);
  padding-left: 10px;
}

/* ---------- prose ---------- */

.prose { min-width: 0; max-width: 820px; }

.prose .eyebrow { margin-bottom: 14px; }

.prose h1 {
  font-size: clamp(2.4rem, 5vw, 3.6rem);
  line-height: 1.02;
  letter-spacing: -0.04em;
  margin: 0 0 16px;
  font-weight: 700;
}

/* Home hero */
.home .prose h1 {
  font-size: clamp(3rem, 8vw, 6rem);
  letter-spacing: -0.06em;
  margin: 8px 0 20px;
}
.home .prose .lede {
  font-size: 1.12rem;
  color: var(--muted);
  max-width: 60ch;
}
.home .docs-shell {
  padding-top: 12vh;
  padding-bottom: 8vh;
}

.prose h2 {
  margin: 60px 0 16px;
  font-size: 1.5rem;
  letter-spacing: -0.02em;
  line-height: 1.25;
  scroll-margin-top: 84px;
}

.prose h3 {
  margin: 38px 0 12px;
  font-size: 1.1rem;
  letter-spacing: -0.01em;
  scroll-margin-top: 84px;
}

.prose p { margin: 0 0 18px; }

.prose a:not(.actions a) {
  color: var(--accent);
  text-decoration: underline;
  text-decoration-color: color-mix(in srgb, var(--accent) 40%, transparent);
  text-underline-offset: 3px;
}
.prose a:hover { text-decoration-color: var(--accent); }

.prose strong { color: var(--fg); font-weight: 700; }

.prose ul, .prose ol {
  margin: 0 0 20px;
  padding-left: 24px;
}

.prose li { margin: 5px 0; }

.prose li::marker {
  color: var(--muted);
  font-family: var(--mono);
}

.prose code {
  font-family: var(--mono);
  font-size: 0.88em;
  background: var(--surface);
  border: 1px solid var(--border);
  padding: 1px 5px;
  color: var(--fg);
}

.prose pre {
  position: relative;
  margin: 0 0 24px;
  padding: 20px 20px 18px;
  background: var(--surface);
  border: 1px solid var(--border);
  overflow: auto;
}

.prose pre code {
  display: block;
  background: none;
  border: none;
  padding: 0;
  font-size: 13px;
  line-height: 1.6;
  color: #cfd6de;
}

.copy {
  position: absolute;
  top: 8px;
  right: 8px;
  background: none;
  border: 1px solid var(--border);
  color: var(--muted);
  font: 11px var(--mono);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 3px 8px;
  cursor: pointer;
}
.copy:hover { color: var(--accent); border-color: var(--accent); }

.prose table {
  width: 100%;
  max-width: 100%;
  overflow-x: auto;
  border-collapse: collapse;
  margin: 0 0 26px;
  font-size: 14.5px;
  display: block;
}

.prose th {
  font: 11px var(--mono);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--dim);
  text-align: left;
  padding: 8px 14px 8px 0;
  border-bottom: 1px solid var(--border-strong);
  white-space: nowrap;
}

.prose td {
  padding: 10px 14px 10px 0;
  border-bottom: 1px solid var(--border);
  vertical-align: top;
}

.prose tr:last-child td { border-bottom: none; }

.prose td:first-child {
  font-family: var(--mono);
  font-size: 13px;
  color: var(--accent);
  white-space: nowrap;
}

.prose blockquote {
  margin: 24px 0;
  padding: 14px 20px;
  border-left: 2px solid var(--accent);
  background: var(--surface);
  color: var(--muted);
}

.prose blockquote p { margin: 0; }

.prose img {
  display: block;
  max-width: 100%;
  height: auto;
  border: 1px solid var(--border);
  margin: 0 0 26px;
}

.prose hr {
  border: none;
  border-top: 1px solid var(--border);
  margin: 40px 0;
}

/* Action buttons on the home page */
.actions {
  display: flex;
  gap: 14px;
  margin: 34px 0 30px;
}

.actions a {
  padding: 10px 14px;
  border: 1px solid var(--border);
  text-decoration: none;
  font: 12px var(--mono);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}
.actions a:first-child { border-color: var(--accent); color: var(--accent); }
.actions a:hover { color: var(--accent); border-color: var(--accent); }

/* ---------- footer ---------- */

footer {
  max-width: var(--max);
  margin: 0 auto;
  padding: 26px 28px;
  display: flex;
  justify-content: space-between;
  gap: 14px;
  border-top: 1px solid var(--border);
  font: 12px var(--mono);
  letter-spacing: 0.08em;
  color: var(--muted);
}

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

/* ---------- small screens ---------- */

@media (max-width: 700px) {
  .header-inner, .docs-shell, footer { padding-left: 18px; padding-right: 18px; }

  .menu-toggle { display: block; margin-left: auto; }

  .nav-main {
    display: none;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    padding: 12px 18px 18px;
    background: var(--surface);
    border-bottom: 1px solid var(--border);
  }

  .nav-main[data-open="true"] { display: flex; }
  .nav-main a, .nav-main .accent-toggle { text-align: left; padding: 9px 4px; }

  .docs-shell { display: block; padding-top: 34px; }
  body.docs .docs-shell { padding-top: 24px; gap: 0; }
  .home .docs-shell { padding-top: 6vh; }
  .docs-rail { margin-bottom: 34px; }
  footer { display: block; }
  footer span { display: block; margin: 5px 0; }
}

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