.site-header { position: fixed; inset-block-start: 0; inset-inline: 0; z-index: 50; transition: background var(--dur-med), border-color var(--dur-med), backdrop-filter var(--dur-med); border-bottom: 1px solid transparent; }
.site-header.is-solid, .site-header.menu-open { background: rgba(11,16,32,.86); backdrop-filter: blur(16px); border-bottom-color: rgba(255,255,255,.1); }
.navbar { min-height: 82px; display: flex; align-items: center; justify-content: space-between; gap: 24px; }
.brand { display: flex; align-items: center; gap: 12px; font-family: "Space Grotesk", "Segoe UI", sans-serif; font-weight: 600; font-size: 20px; letter-spacing: .18em; }
.brand > span { display: inline-flex; align-items: baseline; gap: 8px; line-height: 1; }
.brand-ai { background: var(--grad-wordmark); -webkit-background-clip: text; background-clip: text; color: transparent; }
.brand-hmai { font-weight: 700; letter-spacing: .2em; background: linear-gradient(90deg, #4F7DFF, #7C3AED, #EC4899, #22D3EE); -webkit-background-clip: text; background-clip: text; color: transparent; }
.brand-divider { font-weight: 300; color: rgba(226,230,240,.32); letter-spacing: 0; transform: scaleY(1.15); }
.nav-links { display: flex; align-items: center; gap: 18px; font-size: 14px; }
.nav-links a { position: relative; color: rgba(226,230,240,.78); transition: color var(--dur-fast); }
.nav-links a::after { content: ""; position: absolute; left: 50%; right: 50%; bottom: -8px; height: 2px; background: var(--grad-tagline); transition: left var(--dur-med), right var(--dur-med); }
.nav-links a:hover, .nav-links a.is-active { color: var(--cyan-glow); }
.nav-links a:hover::after, .nav-links a.is-active::after { left: 0; right: 0; }
.nav-cta { margin-inline-start: 4px; }
.menu-toggle { display: none; width: 44px; height: 44px; border-radius: 12px; border: 1px solid rgba(255,255,255,.14); background: rgba(255,255,255,.05); color: var(--cloud-white); }
.menu-toggle span { display: block; width: 18px; height: 2px; background: currentColor; margin: 4px auto; transition: transform var(--dur-med), opacity var(--dur-med); }
@media (max-width: 1080px) {
  .menu-toggle { display: block; }
  .nav-links { position: fixed; inset: 82px 0 auto 0; min-height: calc(100vh - 82px); flex-direction: column; align-items: stretch; padding: 32px 24px; background: rgba(8,16,32,.97); transform: translateY(-110%); opacity: 0; pointer-events: none; transition: transform var(--dur-med) var(--ease), opacity var(--dur-med) var(--ease); }
  .site-header.menu-open .nav-links { transform: translateY(0); opacity: 1; pointer-events: auto; }
  .nav-links a { padding: 14px; font-size: 20px; }
  .nav-cta { margin: 20px 14px 0; }
}
@media (max-width: 520px) {
  .brand { gap: 8px; letter-spacing: .12em; font-size: 16px; }
}