/* ============================================
   SITE HEADER & NAVIGATION
   ============================================ */

.site-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: var(--z-sticky);
    padding: var(--space-4) 0;
    transition: background-color var(--transition-base), border-color var(--transition-base);
    border-bottom: 1px solid transparent;
}

.site-header.is-scrolled {
    background-color: rgba(10, 10, 10, 0.95);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom-color: var(--border-color);
}

/* Nav layout */
.nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-8);
}

/* Logo */
.nav__logo {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    color: var(--text-primary);
    flex-shrink: 0;
}

.nav__logo:hover {
    color: var(--text-primary);
}

.nav__logo-icon {
    color: var(--accent);
}

.nav__logo-text {
    font-family: var(--font-display);
    font-size: var(--text-lg);
    font-weight: 700;
    letter-spacing: -0.02em;
}

/* Desktop nav links */
.nav__links {
    display: none;
    align-items: center;
    gap: var(--space-1);
}

@media (min-width: 1024px) {
    .nav__links {
        display: flex;
    }
}

.nav__link {
    position: relative;
    padding: var(--space-2) var(--space-4);
    font-size: var(--text-sm);
    color: var(--text-secondary);
    transition: color var(--transition-fast);
    letter-spacing: 0.01em;
}

.nav__link:hover {
    color: var(--text-primary);
}

.nav__link--active {
    color: var(--text-primary);
}

.nav__link--active::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: var(--space-4);
    right: var(--space-4);
    height: 2px;
    background: var(--accent);
}

/* Actions */
.nav__actions {
    display: flex;
    align-items: center;
    gap: var(--space-4);
}

/* Hamburger toggle */
.nav__toggle {
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    width: 32px;
    height: 32px;
    padding: 4px;
}

@media (min-width: 1024px) {
    .nav__toggle {
        display: none;
    }
}

.nav__toggle-bar {
    display: block;
    width: 100%;
    height: 2px;
    background: var(--text-primary);
    transition: all var(--transition-base);
    transform-origin: center;
}

.nav__toggle.is-active .nav__toggle-bar:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
}

.nav__toggle.is-active .nav__toggle-bar:nth-child(2) {
    opacity: 0;
}

.nav__toggle.is-active .nav__toggle-bar:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
}

/* Mobile nav overlay */
.nav__mobile {
    position: fixed;
    inset: 0;
    background: rgba(10, 10, 10, 0.98);
    z-index: calc(var(--z-sticky) - 1);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--transition-base), visibility var(--transition-base);
}

.nav__mobile.is-open {
    opacity: 1;
    visibility: visible;
}

.nav__mobile-inner {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-4);
}

.nav__mobile-link {
    font-family: var(--font-display);
    font-size: var(--text-3xl);
    font-weight: 700;
    color: var(--text-secondary);
    transition: color var(--transition-fast);
    padding: var(--space-2);
}

.nav__mobile-link:hover,
.nav__mobile-link.nav__link--active {
    color: var(--text-primary);
}