/* Sirius Looper — site.css
   Design tokens mirror OTTO's palette (Source/OTTOColours.h). When the
   shared L&F submodule lands, this file is the propagation point. */

:root {
  --surface-0: #0a0a0a;
  --surface-1: #141414;
  --surface-2: #1f1f1f;
  --surface-3: #2a2a2a;
  --border:    #2a2a2a;
  --border-hi: #3a3a3a;

  --accent:        #00d4aa;
  --accent-bright: #00ffd0;
  --accent-dim:    #00a085;

  --text-hi:  #f5f5f5;
  --text-mid: #b8b8b8;
  --text-lo:  #6e6e6e;

  --font-display: "Orbitron", ui-sans-serif, system-ui, sans-serif;
  --font-body:    "Inter", ui-sans-serif, system-ui, -apple-system, sans-serif;
  --font-mono:    "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, monospace;

  --step--1: 0.8rem;
  --step-0:  1rem;
  --step-1:  1.25rem;
  --step-2:  1.563rem;
  --step-3:  1.953rem;
  --step-4:  2.441rem;
  --step-5:  3.052rem;
  --step-6:  3.815rem;

  --measure: 68ch;
  --radius:  10px;
  --radius-sm: 6px;
  --shadow-1: 0 1px 0 rgba(255,255,255,0.04) inset, 0 6px 24px rgba(0,0,0,0.4);
}

* { box-sizing: border-box; }

html { background: var(--surface-0); }
body {
  margin: 0;
  background: var(--surface-0);
  color: var(--text-hi);
  font-family: var(--font-body);
  font-size: var(--step-0);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

a { color: var(--accent); text-decoration: none; }
a:hover, a:focus { color: var(--accent-bright); text-decoration: underline; text-underline-offset: 3px; }
a:focus-visible { outline: 2px solid var(--accent-bright); outline-offset: 3px; border-radius: 2px; }

img, svg { max-width: 100%; height: auto; display: block; }

.container { max-width: 1140px; margin: 0 auto; padding: 0 1.25rem; }

/* ---------- Skip link / a11y ---------- */
.skip-link {
  position: absolute; left: -9999px; top: 0;
  background: var(--accent); color: var(--surface-0);
  padding: .5rem .75rem; font-weight: 600;
}
.skip-link:focus { left: 1rem; top: 1rem; z-index: 100; }

/* ---------- Header ---------- */
.site-header {
  position: sticky; top: 0; z-index: 10;
  background: rgba(10,10,10,0.85);
  backdrop-filter: saturate(140%) blur(10px);
  -webkit-backdrop-filter: saturate(140%) blur(10px);
  border-bottom: 1px solid var(--border);
}
.header-row {
  display: flex; align-items: center; justify-content: space-between;
  height: 64px;
}
.brand {
  font-family: var(--font-display);
  letter-spacing: 0.08em;
  color: var(--text-hi);
  font-weight: 700;
  font-size: var(--step-0);
  display: inline-flex; gap: .5rem; align-items: baseline;
}
.brand:hover { text-decoration: none; color: var(--text-hi); }
.brand-mark-accent { color: var(--accent); }
.brand-suffix { color: var(--text-mid); font-weight: 500; letter-spacing: 0.12em; }

.site-nav { display: flex; gap: 1.25rem; align-items: center; }
.site-nav a {
  color: var(--text-mid);
  font-size: var(--step--1);
  font-weight: 500;
  letter-spacing: 0.02em;
  padding: .5rem 0;
}
.site-nav a:hover { color: var(--text-hi); text-decoration: none; }
.site-nav a[aria-current="page"] { color: var(--accent); }
.site-nav .nav-external::after {
  content: " ↗"; color: var(--text-lo); font-size: 0.85em;
}

@media (max-width: 720px) {
  .site-nav { gap: .75rem; }
  .site-nav .nav-external { display: none; }
}

/* ---------- Hero ---------- */
.hero {
  padding: clamp(3rem, 8vw, 7rem) 0 clamp(2.5rem, 6vw, 5rem);
  background:
    radial-gradient(ellipse 80% 60% at 50% 0%, rgba(0,212,170,0.10), transparent 60%),
    linear-gradient(180deg, var(--surface-0) 0%, var(--surface-0) 100%);
  border-bottom: 1px solid var(--border);
}
.hero-kicker {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: var(--step--1);
  color: var(--accent);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  margin: 0 0 1rem;
}
.hero h1 {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(2rem, 5vw, var(--step-5));
  line-height: 1.1;
  margin: 0 0 1.25rem;
  letter-spacing: -0.01em;
  max-width: 22ch;
}
.hero-lede {
  font-size: clamp(1.05rem, 1.6vw, var(--step-1));
  color: var(--text-mid);
  max-width: var(--measure);
  margin: 0 0 2rem;
}
.hero-cta { display: flex; flex-wrap: wrap; gap: 1rem; align-items: center; }

/* ---------- Signup form ---------- */
.signup-form {
  display: flex; gap: .5rem; align-items: stretch;
  background: var(--surface-1);
  border: 1px solid var(--border-hi);
  border-radius: var(--radius);
  padding: .35rem .35rem .35rem .9rem;
  max-width: 460px;
  box-shadow: var(--shadow-1);
}
.signup-form input[type="email"] {
  flex: 1;
  background: transparent;
  border: 0;
  color: var(--text-hi);
  font: inherit;
  outline: none;
  padding: .65rem 0;
  min-width: 0;
}
.signup-form input[type="email"]::placeholder { color: var(--text-lo); }
.signup-form .honeypot { position: absolute; left: -9999px; }
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  font-family: var(--font-body);
  font-weight: 600;
  font-size: var(--step-0);
  padding: .65rem 1.1rem;
  border-radius: var(--radius-sm);
  border: 1px solid transparent;
  cursor: pointer;
  transition: background-color .15s, color .15s, border-color .15s, transform .05s;
  text-decoration: none;
}
.btn:active { transform: translateY(1px); }
.btn-primary { background: var(--accent); color: #00231c; }
.btn-primary:hover, .btn-primary:focus { background: var(--accent-bright); color: #00231c; text-decoration: none; }
.btn-ghost {
  background: transparent;
  color: var(--text-hi);
  border-color: var(--border-hi);
}
.btn-ghost:hover, .btn-ghost:focus { border-color: var(--accent); color: var(--accent); text-decoration: none; }
.signup-status {
  margin: .75rem 0 0;
  font-size: var(--step--1);
  color: var(--text-mid);
  min-height: 1.2em;
}
.signup-status.is-success { color: var(--accent); }
.signup-status.is-error { color: #ff8a8a; }

/* ---------- Sections ---------- */
.section {
  padding: clamp(3rem, 6vw, 5rem) 0;
  border-bottom: 1px solid var(--border);
}
.section h2 {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.6rem, 3vw, var(--step-3));
  letter-spacing: -0.005em;
  margin: 0 0 .75rem;
}
.section-lede {
  color: var(--text-mid);
  max-width: var(--measure);
  margin: 0 0 2.5rem;
  font-size: var(--step-1);
}

/* ---------- Pillar cards ---------- */
.pillars {
  display: grid;
  gap: 1rem;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
}
.pillar {
  background: var(--surface-1);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.5rem;
  transition: border-color .2s, transform .2s;
}
.pillar:hover { border-color: var(--accent-dim); transform: translateY(-2px); }
.pillar .pillar-icon {
  width: 36px; height: 36px;
  display: inline-flex; align-items: center; justify-content: center;
  border-radius: 8px;
  background: rgba(0,212,170,0.10);
  color: var(--accent);
  margin-bottom: 1rem;
}
.pillar h3 {
  font-family: var(--font-display);
  font-size: var(--step-1);
  margin: 0 0 .5rem;
  font-weight: 700;
  letter-spacing: 0.01em;
}
.pillar p { color: var(--text-mid); margin: 0; }

/* ---------- Hero illustration (tape with moving in-point) ---------- */
.tape-illo { margin-top: 3rem; }
.tape-illo svg { width: 100%; max-width: 880px; margin: 0 auto; }
.tape-region { fill: rgba(0,212,170,0.18); stroke: var(--accent); stroke-width: 1.5; }
.tape-base { fill: var(--surface-1); stroke: var(--border-hi); }
.tape-tick { stroke: var(--text-lo); stroke-width: 1; }
.tape-playhead { stroke: var(--accent-bright); stroke-width: 2; }
.tape-marker {
  animation: markerSlide 6s ease-in-out infinite;
  transform-origin: center;
}
@keyframes markerSlide {
  0%, 100% { transform: translateX(0); }
  45%      { transform: translateX(180px); }
  55%      { transform: translateX(180px); }
}
@media (prefers-reduced-motion: reduce) {
  .tape-marker { animation: none; }
}

/* ---------- Features list ---------- */
.feature-list {
  display: grid; gap: 1.5rem;
  grid-template-columns: 1fr;
  margin-top: 2rem;
}
@media (min-width: 800px) { .feature-list { grid-template-columns: 1fr 1fr; } }
.feature {
  background: var(--surface-1);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.75rem;
}
.feature-tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: var(--step--1);
  color: var(--accent);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  margin: 0 0 .5rem;
}
.feature h3 {
  font-family: var(--font-display);
  font-size: var(--step-2);
  margin: 0 0 .75rem;
  font-weight: 700;
  letter-spacing: -0.005em;
}
.feature p { color: var(--text-mid); margin: 0 0 .75rem; }
.feature .term { font-family: var(--font-mono); color: var(--text-hi); }

/* ---------- Architecture quote blocks ---------- */
.arch-block { margin: 2.5rem 0; }
.arch-block h3 {
  font-family: var(--font-display);
  font-size: var(--step-2);
  margin: 0 0 1rem;
  font-weight: 700;
}
.arch-block blockquote {
  margin: 0 0 1rem;
  padding: 1.25rem 1.5rem;
  border-left: 3px solid var(--accent);
  background: var(--surface-1);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  font-size: var(--step-1);
  color: var(--text-hi);
}
.arch-block blockquote cite {
  display: block;
  margin-top: .75rem;
  font-size: var(--step--1);
  color: var(--text-lo);
  font-style: normal;
  font-family: var(--font-mono);
}
.arch-block .arch-prose { color: var(--text-mid); max-width: var(--measure); }

/* ---------- Closing band ---------- */
.band {
  padding: clamp(2.5rem, 5vw, 4rem) 0;
  background:
    linear-gradient(180deg, rgba(0,212,170,0.06), transparent 70%),
    var(--surface-0);
  text-align: center;
}
.band h2 {
  font-family: var(--font-display);
  font-size: var(--step-3);
  margin: 0 0 1rem;
}
.band p { color: var(--text-mid); margin: 0 auto 1.5rem; max-width: var(--measure); }

/* ---------- About ---------- */
.about-section h2 {
  font-family: var(--font-display);
  font-size: var(--step-2);
  margin: 2rem 0 .75rem;
}
.about-section p { color: var(--text-mid); max-width: var(--measure); }

/* ---------- 404 ---------- */
.error-page { padding: 6rem 0; text-align: center; }
.error-page .error-code {
  font-family: var(--font-display);
  font-size: var(--step-6);
  color: var(--accent);
  margin: 0 0 1rem;
}
.error-page p { color: var(--text-mid); max-width: 40ch; margin: 0 auto 1.5rem; }

/* ---------- Footer ---------- */
.site-footer {
  margin-top: 4rem;
  padding: 3rem 0 1.5rem;
  background: var(--surface-1);
  border-top: 1px solid var(--border);
}
.footer-grid {
  display: grid;
  gap: 2rem;
  grid-template-columns: 2fr 1fr 1fr 1fr;
}
@media (max-width: 720px) { .footer-grid { grid-template-columns: 1fr 1fr; } }
.footer-block h4 {
  font-family: var(--font-display);
  font-size: var(--step--1);
  color: var(--text-mid);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  margin: 0 0 .75rem;
}
.footer-block ul { list-style: none; padding: 0; margin: 0; }
.footer-block li { margin: .3rem 0; }
.footer-block a { color: var(--text-mid); }
.footer-block a:hover { color: var(--accent); }
.footer-brand {
  font-family: var(--font-display);
  letter-spacing: 0.08em;
  color: var(--text-hi);
  font-weight: 700;
  margin-bottom: .5rem;
}
.footer-tag { color: var(--text-lo); margin: 0; max-width: 36ch; }
.footer-meta {
  margin-top: 2rem;
  padding-top: 1rem;
  border-top: 1px solid var(--border);
  color: var(--text-lo);
}

/* ---------- Prose (markdown docs) ---------- */
.prose {
  max-width: var(--measure);
  color: var(--text-hi);
}
.prose h1 {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: var(--step-4);
  letter-spacing: -0.01em;
  margin: 0 0 1rem;
}
.prose .doc-subtitle {
  font-size: var(--step-1);
  color: var(--text-mid);
  margin: 0 0 2rem;
}
.prose h2 {
  font-family: var(--font-display);
  font-size: var(--step-2);
  margin: 2.5rem 0 .75rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border);
}
.prose h3 { font-family: var(--font-display); font-size: var(--step-1); margin: 1.75rem 0 .5rem; }
.prose h4 { font-size: var(--step-0); color: var(--text-mid); text-transform: uppercase; letter-spacing: 0.1em; margin: 1.5rem 0 .5rem; }
.prose p, .prose li { color: var(--text-mid); }
.prose strong { color: var(--text-hi); }
.prose em { color: var(--text-hi); }
.prose a { color: var(--accent); }
.prose ul, .prose ol { padding-left: 1.25rem; }
.prose blockquote {
  margin: 1.25rem 0;
  padding: .25rem 0 .25rem 1rem;
  border-left: 3px solid var(--accent-dim);
  color: var(--text-mid);
  font-style: italic;
}
.prose code {
  font-family: var(--font-mono);
  font-size: 0.92em;
  background: var(--surface-1);
  border: 1px solid var(--border);
  padding: 1px 6px;
  border-radius: 4px;
  color: var(--text-hi);
}
.prose pre {
  background: var(--surface-1);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 1rem;
  overflow-x: auto;
}
.prose pre code { background: none; border: 0; padding: 0; }
.prose table {
  border-collapse: collapse;
  width: 100%;
  margin: 1.5rem 0;
  font-size: var(--step--1);
}
.prose th, .prose td {
  border: 1px solid var(--border);
  padding: .5rem .75rem;
  text-align: left;
  vertical-align: top;
}
.prose th { background: var(--surface-1); color: var(--text-hi); font-weight: 600; }
.prose hr { border: 0; border-top: 1px solid var(--border); margin: 2rem 0; }

/* ---------- Doc layout (aside + body) ---------- */
.doc { padding: 3rem 0 4rem; }
.doc-grid {
  display: grid;
  gap: 2.5rem;
  grid-template-columns: 240px 1fr;
}
@media (max-width: 900px) { .doc-grid { grid-template-columns: 1fr; } .doc-aside { order: 2; } }
.doc-aside-inner { position: sticky; top: 88px; }
.doc-kicker {
  font-family: var(--font-mono);
  font-size: var(--step--1);
  color: var(--accent);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  margin: 0 0 .5rem;
}
.doc-title-aside {
  font-family: var(--font-display);
  font-size: var(--step-0);
  color: var(--text-hi);
  margin: 0 0 1.25rem;
}
.doc-toc-label {
  font-size: var(--step--1);
  color: var(--text-mid);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin: 1rem 0 .5rem;
}
.doc-toc ol { list-style: none; padding: 0; margin: 0; }
.doc-toc li { margin: .25rem 0; }
.doc-toc a { color: var(--text-mid); font-size: var(--step--1); display: block; padding: .2rem 0; }
.doc-toc a:hover { color: var(--accent); text-decoration: none; }
.doc-aside-meta { margin-top: 1.5rem; font-size: var(--step--1); }

/* ---------- Selection ---------- */
::selection { background: var(--accent); color: var(--surface-0); }