/* ===========================================================
   Chouniu Labs — Shared Styles
   =========================================================== */

@import url('https://fonts.googleapis.com/css2?family=Space+Grotesk:wght@400;500;600;700&family=Inter:wght@400;500;600&family=JetBrains+Mono:wght@400;500&display=swap');

:root {
  --bg: #F4F6F4;
  --surface: #FFFFFF;
  --ink: #0E1512;
  --muted: #5B645F;
  --line: #D7DDD9;
  --accent: #FF5A36;
  --accent-ink: #FFF3EF;
  --lab-green: #0B6E4F;
  --lab-green-soft: #E6F1EC;

  --font-display: 'Space Grotesk', sans-serif;
  --font-body: 'Inter', sans-serif;
  --font-mono: 'JetBrains Mono', monospace;

  --container: 1180px;
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  background-image:
    linear-gradient(var(--line) 1px, transparent 1px),
    linear-gradient(90deg, var(--line) 1px, transparent 1px);
  background-size: 64px 64px;
  background-position: -1px -1px;
  background-attachment: fixed;
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }

.wrap {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 32px;
}

.mono {
  font-family: var(--font-mono);
  letter-spacing: 0.02em;
}

.eyebrow {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--lab-green);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 16px;
}

.eyebrow::before {
  content: '';
  width: 7px;
  height: 7px;
  background: var(--accent);
  border-radius: 1px;
}

h1, h2, h3 {
  font-family: var(--font-display);
  font-weight: 600;
  line-height: 1.1;
  margin: 0 0 0.4em;
  letter-spacing: -0.01em;
}

h1 { font-size: clamp(40px, 6vw, 76px); font-weight: 700; }
h2 { font-size: clamp(28px, 3.4vw, 42px); }
h3 { font-size: 20px; }

p { margin: 0 0 1em; color: var(--muted); }

.section {
  padding: 96px 0;
  border-bottom: 1px solid var(--line);
}

.section-head {
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  gap: 24px;
  margin-bottom: 56px;
  flex-wrap: wrap;
}

.section-index {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--muted);
  white-space: nowrap;
}

/* ---------- Header ---------- */

header.site {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(244, 246, 244, 0.86);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 0;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 19px;
}

.logo-mark {
  width: 28px;
  height: 28px;
  border: 1.5px solid var(--ink);
  border-radius: 4px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 500;
  background: var(--ink);
  color: var(--bg);
}

.nav-links {
  display: flex;
  gap: 4px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-links a {
  font-family: var(--font-mono);
  font-size: 13.5px;
  color: var(--muted);
  padding: 8px 14px;
  border-radius: 4px;
  transition: color 0.15s ease, background 0.15s ease;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--ink);
  background: var(--surface);
}

.nav-links a.active {
  color: var(--lab-green);
}

.nav-cta {
  font-family: var(--font-mono);
  font-size: 13px;
  border: 1px solid var(--ink);
  padding: 9px 16px;
  border-radius: 4px;
  transition: background 0.15s ease, color 0.15s ease;
}

.nav-cta:hover {
  background: var(--ink);
  color: var(--bg);
}

.nav-toggle {
  display: none;
  background: none;
  border: 1px solid var(--line);
  border-radius: 4px;
  width: 40px;
  height: 40px;
  align-items: center;
  justify-content: center;
  cursor: pointer;
}

@media (max-width: 860px) {
  .nav-links { display: none; }
  .nav-toggle { display: flex; }
  .nav-cta { display: none; }

  .nav-links.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--bg);
    border-bottom: 1px solid var(--line);
    padding: 8px 16px 16px;
  }

  .nav-links.open a {
    padding: 12px 8px;
  }

  header.site { position: sticky; }
  .nav { position: relative; }
}

/* ---------- Buttons ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 14px;
  padding: 13px 22px;
  border-radius: 4px;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 0.15s ease, background 0.15s ease, color 0.15s ease, border-color 0.15s ease;
}

.btn-primary {
  background: var(--ink);
  color: var(--bg);
}
.btn-primary:hover { background: var(--accent); transform: translateY(-1px); }

.btn-outline {
  border-color: var(--ink);
  color: var(--ink);
}
.btn-outline:hover { background: var(--ink); color: var(--bg); }

/* ---------- Footer ---------- */

footer.site {
  padding: 64px 0 32px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: 40px;
  padding-bottom: 48px;
  border-bottom: 1px solid var(--line);
}

.footer-grid h4 {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin: 0 0 16px;
}

.footer-grid ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-grid a { font-size: 14.5px; color: var(--ink); }
.footer-grid a:hover { color: var(--accent); }

.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 24px;
  font-family: var(--font-mono);
  font-size: 12.5px;
  color: var(--muted);
  flex-wrap: wrap;
  gap: 12px;
}

@media (max-width: 720px) {
  .footer-grid { grid-template-columns: 1fr 1fr; }
}

/* ---------- Cards ---------- */

.card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 32px;
  transition: border-color 0.2s ease, transform 0.2s ease;
}

.card:hover {
  border-color: var(--ink);
  transform: translateY(-2px);
}

.tag {
  font-family: var(--font-mono);
  font-size: 11.5px;
  color: var(--lab-green);
  background: var(--lab-green-soft);
  padding: 4px 9px;
  border-radius: 3px;
  display: inline-block;
}

/* ---------- Page hero (inner pages) ---------- */

.page-hero {
  padding: 72px 0 56px;
  border-bottom: 1px solid var(--line);
}

.page-hero .eyebrow { margin-bottom: 20px; }

.page-hero p.lead {
  font-size: 18px;
  max-width: 640px;
  color: var(--muted);
}

/* ---------- utility ---------- */

.grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: 32px; }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }

@media (max-width: 900px) {
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .section { padding: 64px 0; }
}

.divider {
  height: 1px;
  background: var(--line);
  border: none;
  margin: 0;
}