/* layout.css — grid, header, footer, sections */
.container {
  width: 100%;
  max-width: var(--grid-max);
  margin: 0 auto;
  padding: 0 var(--space-4);
}

.section { padding: var(--space-7) 0; }
.section--tight { padding: var(--space-6) 0; }
.section--paper2 { background: var(--paper-2); }
.section--ink { background: var(--ink); color: var(--paper); }
.section--ink h1, .section--ink h2, .section--ink h3 { color: var(--paper); }

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

/* ---- Header ---- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255,255,255,.92);
  backdrop-filter: saturate(180%) blur(10px);
  border-bottom: 1px solid var(--line);
}
.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 70px;
}
.brand {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-family: var(--ff-display);
  font-weight: 700;
  font-size: 1.15rem;
  letter-spacing: -0.02em;
  color: var(--ink);
}
.brand:hover { color: var(--ink); }
.brand .mark {
  width: 30px; height: 30px;
  flex: 0 0 auto;
}
.brand small {
  display: block;
  font-family: var(--ff-body);
  font-weight: 500;
  font-size: 0.62rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--mono);
}
.nav-links {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  list-style: none;
  margin: 0; padding: 0;
}
.nav-links a {
  font-family: var(--ff-display);
  font-weight: 500;
  font-size: 0.92rem;
  position: relative;
  padding: 4px 0;
}
.nav-links a::after {
  content: "";
  position: absolute;
  left: 0; bottom: -2px;
  width: 0; height: 2px;
  background: var(--red);
  transition: width .28s var(--ease);
}
.nav-links a:hover::after,
.nav-links a[aria-current="page"]::after { width: 100%; }
.nav-links a[aria-current="page"] { color: var(--red); }

.nav-toggle {
  display: none;
  width: 44px; height: 44px;
  border: 1px solid var(--line);
  background: var(--paper);
  border-radius: var(--radius);
  cursor: pointer;
  align-items: center;
  justify-content: center;
}
.nav-toggle span,
.nav-toggle span::before,
.nav-toggle span::after {
  content: "";
  display: block;
  width: 20px; height: 2px;
  background: var(--ink);
  transition: transform .3s var(--ease), opacity .3s var(--ease);
}
.nav-toggle span { position: relative; }
.nav-toggle span::before { position: absolute; top: -6px; }
.nav-toggle span::after { position: absolute; top: 6px; }
.nav-toggle[aria-expanded="true"] span { background: transparent; }
.nav-toggle[aria-expanded="true"] span::before { transform: translateY(6px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span::after { transform: translateY(-6px) rotate(-45deg); }

/* ---- Footer ---- */
.site-footer {
  background: var(--ink);
  color: #c9c9cc;
  padding: var(--space-6) 0 var(--space-4);
  font-size: 0.92rem;
}
.site-footer a { color: #e7e7e9; }
.site-footer a:hover { color: #fff; }
.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: var(--space-5);
  margin-bottom: var(--space-5);
}
.footer-grid h4 {
  font-family: var(--ff-display);
  color: #fff;
  font-size: 0.78rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  margin-bottom: var(--space-3);
}
.footer-grid ul { list-style: none; padding: 0; margin: 0; }
.footer-grid li { margin-bottom: var(--space-2); }
.footer-brand .brand { color: #fff; margin-bottom: var(--space-3); }
.footer-brand .brand:hover { color: #fff; }
.footer-bottom {
  border-top: 1px solid #2a2a30;
  padding-top: var(--space-4);
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-2);
  font-size: 0.82rem;
  color: #8a8a90;
}
.social-row { display: flex; gap: var(--space-3); }
.social-row a {
  width: 36px; height: 36px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: 1px solid #33333a;
  border-radius: var(--radius);
  transition: border-color .25s var(--ease), background .25s var(--ease);
}
.social-row a:hover { border-color: var(--red); background: var(--red); }
.social-row svg { width: 18px; height: 18px; fill: currentColor; }

/* ---- Responsive ---- */
@media (max-width: 900px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; gap: var(--space-4); }
}
@media (max-width: 760px) {
  .nav-toggle { display: inline-flex; }
  .nav-links {
    position: absolute;
    top: 70px; left: 0; right: 0;
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
    background: var(--paper);
    border-bottom: 1px solid var(--line);
    padding: var(--space-2) var(--space-4);
    max-height: 0;
    overflow: hidden;
    transition: max-height .35s var(--ease);
  }
  .nav-links.open { max-height: 420px; }
  .nav-links li { width: 100%; border-bottom: 1px solid var(--paper-3); }
  .nav-links li:last-child { border-bottom: 0; }
  .nav-links a { display: block; padding: 14px 0; width: 100%; }
}
@media (max-width: 560px) {
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .section { padding: var(--space-6) 0; }
}