/* ========================================
   HEADER / NAVIGATION
   ======================================== */

.site-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    height: var(--header-height);
    transition:
        background-color var(--duration-base) var(--ease-out),
        box-shadow var(--duration-base) var(--ease-out);
}

/* Scrolled state */
.site-header.is-scrolled {
    background-color: rgba(11, 12, 16, 0.92);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    box-shadow: 0 1px 0 var(--border-subtle);
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
    max-width: var(--container-max);
    margin-inline: auto;
    padding-inline: var(--gutter);
}

/* ---- Logo ---- */
.header-logo {
    display: flex;
    align-items: center;
    z-index: 1001;
    transition: opacity var(--duration-fast) var(--ease-out);
    flex-shrink: 0;
}

.header-logo:hover {
    opacity: 0.85;
}

.logo-img {
    height: 42px;
    width: auto;
    display: block;
}

/* ---- Desktop Navigation ---- */
.header-nav {
    display: none;
    align-items: center;
    gap: 2.5rem;
}

.nav-list {
    display: flex;
    align-items: center;
    gap: 0.25rem;
}

.nav-link {
    font-family: var(--font-body);
    font-size: var(--text-sm);
    font-weight: var(--fw-medium);
    letter-spacing: var(--tracking-wide);
    text-transform: uppercase;
    color: var(--color-grey-300);
    padding: 0.5rem 0.875rem;
    border-radius: var(--radius-sm);
    transition:
        color var(--duration-fast) var(--ease-out),
        background-color var(--duration-fast) var(--ease-out);
    position: relative;
}

.nav-link:hover {
    color: var(--color-white);
}

.nav-link.active {
    color: var(--color-white);
}

.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0.875rem;
    right: 0.875rem;
    height: 2px;
    background-color: var(--color-accent);
    border-radius: 1px;
}

.nav-cta {
    font-family: var(--font-body);
    font-size: var(--text-sm);
    font-weight: var(--fw-semibold);
    letter-spacing: var(--tracking-wide);
    text-transform: uppercase;
    color: var(--color-white);
    padding: 0.625rem 1.25rem;
    background-color: var(--color-accent);
    border: 1px solid var(--color-accent);
    border-radius: var(--radius-sm);
    transition:
        background-color var(--duration-fast) var(--ease-out),
        border-color var(--duration-fast) var(--ease-out);
}

.nav-cta:hover {
    background-color: var(--color-accent-dark);
    border-color: var(--color-accent-dark);
}

/* ---- Mobile Menu Toggle ---- */
.menu-toggle {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 6px;
    width: 40px;
    height: 40px;
    z-index: 1001;
    padding: 8px;
}

.menu-bar {
    display: block;
    width: 22px;
    height: 1.5px;
    background-color: var(--color-white);
    border-radius: 1px;
    transition:
        transform var(--duration-base) var(--ease-out),
        opacity var(--duration-fast) var(--ease-out);
    transform-origin: center;
}

/* Open state */
.menu-toggle[aria-expanded="true"] .menu-bar:first-child {
    transform: translateY(3.75px) rotate(45deg);
}

.menu-toggle[aria-expanded="true"] .menu-bar:last-child {
    transform: translateY(-3.75px) rotate(-45deg);
}

/* ---- Mobile Overlay Navigation ---- */
.header-nav.is-open {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: flex-start;
    position: fixed;
    inset: 0;
    background-color: var(--color-black);
    padding: var(--space-2xl) var(--gutter);
    z-index: 1000;
    animation: navFadeIn var(--duration-base) var(--ease-out);
}

/* Force header solid when menu is open */
.site-header.menu-open {
    background-color: var(--color-black);
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
}

@keyframes navFadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

.header-nav.is-open .nav-list {
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
    width: 100%;
}

.header-nav.is-open .nav-link {
    font-family: var(--font-heading);
    font-size: var(--text-xl);
    font-weight: var(--fw-semibold);
    letter-spacing: var(--tracking-tight);
    text-transform: none;
    color: var(--color-grey-300);
    padding: 0.75rem 0;
    display: block;
    width: 100%;
    border-bottom: 1px solid var(--border-subtle);
    border-radius: 0;
}

.header-nav.is-open .nav-link:hover,
.header-nav.is-open .nav-link.active {
    color: var(--color-white);
}

.header-nav.is-open .nav-link.active::after {
    display: none;
}

.header-nav.is-open .nav-cta {
    margin-top: var(--space-lg);
    font-size: var(--text-base);
    padding: 1rem 2rem;
}

/* ---- Desktop breakpoint ---- */
@media (min-width: 960px) {
    .header-nav {
        display: flex;
    }

    .menu-toggle {
        display: none;
    }

    .logo-img {
        height: 46px;
    }
}