.site-header { background: var(--color-surface); border-bottom: 1px solid var(--color-border); position: sticky; top: 0; z-index: 50; }
.site-header__inner { max-width: var(--container); margin: 0 auto; padding: var(--space-3); display: flex; align-items: center; justify-content: space-between; gap: var(--space-3); }
.site-header__brand { display: inline-flex; align-items: center; gap: 10px; font-weight: 800; font-size: 1.05rem; letter-spacing: -.3px; color: var(--color-text); text-decoration: none; }
.site-header__mark { width: 32px; height: 32px; border-radius: 10px; display: grid; place-items: center; color: #fff; font-weight: 900; background: linear-gradient(145deg, #ff9b70, #e34e33); box-shadow: 0 5px 12px #e65e3d38; }
.site-header__nav ul { list-style: none; margin: 0; padding: 0; display: flex; gap: var(--space-2); }
.site-header__nav a { display: block; padding: 8px 12px; border-radius: 8px; color: var(--color-muted); text-decoration: none; font-weight: 600; }
.site-header__nav a:hover, .site-header__nav a.active { color: var(--color-primary); background: color-mix(in srgb, var(--color-primary) 10%, transparent); }
.site-header__toggle { display: none; background: none; border: 1px solid var(--color-border); border-radius: 8px; font-size: 1.2rem; padding: 4px 10px; cursor: pointer; }

@media (max-width: 720px) {
  .site-header__toggle { display: block; }
  .site-header__nav { display: none; position: absolute; top: 100%; left: 0; right: 0; background: var(--color-surface); border-bottom: 1px solid var(--color-border); }
  .site-header__nav.open { display: block; }
  .site-header__nav ul { flex-direction: column; padding: var(--space-2); }
}