.site-header {
  position: fixed;
  top: 0;
  right: 0;
  left: 0;
  z-index: 100;
  color: var(--color-white);
  transition: background 0.25s ease, color 0.25s ease, border-color 0.25s ease;
}

.site-header.is-scrolled,
.site-header.is-open {
  border-bottom: 1px solid var(--color-border);
  background: rgba(255, 255, 255, 0.94);
  color: var(--color-charcoal);
  backdrop-filter: blur(14px);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: var(--header-height);
  width: min(calc(100% - 32px), var(--content-max));
  margin: 0 auto;
}

.brand-mark {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  font-size: 1.35rem;
  font-weight: 800;
  letter-spacing: 0.08em;
}

.menu-button {
  display: inline-grid;
  place-items: center;
  width: 44px;
  height: 44px;
  border: 0;
  background: transparent;
  color: currentColor;
}

.menu-button span {
  display: block;
  width: 24px;
  height: 2px;
  background: currentColor;
  transition: transform 0.25s ease;
}

.menu-button[aria-expanded="true"] span:first-child {
  transform: translateY(3px) rotate(32deg);
}

.menu-button[aria-expanded="true"] span:last-child {
  transform: translateY(-3px) rotate(-32deg);
}

.site-nav {
  position: fixed;
  inset: var(--header-height) 0 auto 0;
  display: grid;
  gap: 4px;
  transform: translateY(-120%);
  border-bottom: 1px solid var(--color-border);
  background: var(--color-white);
  color: var(--color-charcoal);
  padding: 20px;
  transition: transform 0.28s ease;
}

.site-nav.is-open {
  transform: translateY(0);
}

.site-nav a {
  min-height: 44px;
  border-radius: var(--radius);
  padding: 10px 4px;
  font-size: 0.86rem;
  font-weight: 700;
  letter-spacing: 0.08em;
}

.site-footer {
  background: var(--color-charcoal);
  color: var(--color-white);
  padding: 56px 0 104px;
}

.site-footer__grid {
  display: grid;
  gap: 28px;
}

.site-footer h2 {
  color: var(--color-gray);
  font-size: 0.78rem;
  letter-spacing: 0.1em;
  margin-bottom: 12px;
}

.site-footer a {
  display: block;
  min-height: 36px;
  color: var(--color-light-gray);
}