/* ============================================================
   02-layout.css — Container, section, app shell, nav, footer
   ============================================================ */

.container {
  max-width: 1320px;
  margin: 0 auto;
  padding: 0 clamp(1.25rem, 4vw, 3rem);
}
.section { padding: var(--pad-section) 0; }

.app {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.nav {
  position: sticky; top: 0; z-index: 50;
  background: color-mix(in oklab, var(--bg) 92%, transparent);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--line-2);
}
.nav-inner {
  display: flex; align-items: center; justify-content: space-between;
  height: 76px;
}
.brand {
  display: flex; align-items: center; gap: 0.65rem;
  font-family: var(--font-display);
  font-size: 1.35rem;
  letter-spacing: -0.01em;
}
.brand-logo {
  height: 56px;
  width: auto;
  display: block;
  object-fit: contain;
}
@media (prefers-color-scheme: dark) {
  .brand-logo { filter: invert(1) brightness(1.05); }
  .brand-mark { filter: invert(1) brightness(1.1); }
}
.brand-mark {
  width: 36px; height: 36px;
  display: block;
  flex-shrink: 0;
  object-fit: contain;
}
.nav-links {
  display: flex; gap: 0.25rem; align-items: center;
}
.nav-link {
  padding: 0.55rem 0.9rem;
  font-size: 0.92rem;
  color: var(--ink-2);
  border-radius: var(--radius);
  position: relative;
  transition: color 0.18s ease;
}
.nav-link:hover { color: var(--ink); }
.nav-link.active { color: var(--ink); }
.nav-link.active::after {
  content: "";
  position: absolute;
  left: 0.9rem; right: 0.9rem; bottom: 0.1rem;
  height: 1px;
  background: var(--accent);
}
.nav-cta { margin-left: 0.6rem; }

.footer {
  margin-top: auto;
  border-top: 1px solid var(--line-2);
  padding: 4rem 0 2rem;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 3rem;
  margin-bottom: 3rem;
}
@media (max-width: 800px) {
  .footer-grid { grid-template-columns: 1fr 1fr; }
}
.footer-col h4 {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-3);
  margin-bottom: 1rem;
}
.footer-col a {
  display: block;
  padding: 0.25rem 0;
  color: var(--ink-2);
  font-size: 0.92rem;
}
.footer-col a:hover { color: var(--ink); }
.footer-bottom {
  display: flex; justify-content: space-between;
  padding-top: 2rem;
  border-top: 1px solid var(--line-2);
  font-size: 0.8rem;
  color: var(--ink-3);
  font-family: var(--font-mono);
}