/* ==========================================================================
   Header — Serif Editorial
   ========================================================================== */

.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    padding: var(--space-4) 0;
    transition: all var(--duration) var(--ease-out);
}

.header.is-scrolled {
    background-color: rgba(250, 250, 248, 0.9);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
}

.header .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.header__logo {
    display: flex;
    align-items: center;
    gap: var(--space-3);
}

.header__logo img,
.header__logo svg {
    height: 48px;
    width: auto;
    color: var(--accent);
}

.header__logo-text {
    font-family: var(--font-display);
    font-size: var(--text-title);
    font-weight: 400;
    color: var(--foreground);
    letter-spacing: -0.01em;
}

.nav__list {
    display: flex;
    align-items: center;
    gap: var(--space-8);
}

.nav__link {
    font-size: var(--text-label);
    font-weight: 500;
    letter-spacing: 0.05em;
    color: var(--muted-foreground);
    transition: color var(--duration) var(--ease-out);
    position: relative;
}

.nav__link::after {
    content: '';
    position: absolute;
    left: 0;
    bottom: -4px;
    width: 0;
    height: 1px;
    background-color: var(--accent);
    transition: width var(--duration) var(--ease-out);
}

.nav__link:hover,
.nav__link.is-active {
    color: var(--foreground);
}

.nav__link:hover::after,
.nav__link.is-active::after {
    width: 100%;
}

.nav__cta {
    font-size: var(--text-label);
    font-weight: 500;
    letter-spacing: 0.03em;
    color: var(--accent-foreground);
    background-color: var(--accent);
    padding: var(--space-2) var(--space-6);
    border-radius: var(--radius-md);
    transition: all var(--duration) var(--ease-out);
}

.nav__cta:hover {
    background-color: var(--accent-secondary);
    box-shadow: var(--shadow-sm);
}

/* ── Mobile Toggle ─────────────────────────────────────────────────────── */
.nav__toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    width: 24px;
    padding: 2px 0;
}

.nav__toggle span {
    display: block;
    width: 100%;
    height: 1px;
    background-color: var(--foreground);
    transition: all var(--duration) var(--ease-out);
}

.nav__toggle.is-open span:nth-child(1) {
    transform: translateY(6px) rotate(45deg);
}

.nav__toggle.is-open span:nth-child(2) {
    opacity: 0;
}

.nav__toggle.is-open span:nth-child(3) {
    transform: translateY(-6px) rotate(-45deg);
}

@media (max-width: 768px) {
    .nav__toggle {
        display: flex;
    }

    .nav {
        position: fixed;
        inset: 0;
        background-color: rgba(250, 250, 248, 0.97);
        backdrop-filter: blur(16px);
        -webkit-backdrop-filter: blur(16px);
        display: flex;
        align-items: center;
        justify-content: center;
        opacity: 0;
        pointer-events: none;
        transition: opacity var(--duration) var(--ease-out);
        z-index: 99;
    }

    .nav.is-open {
        opacity: 1;
        pointer-events: auto;
    }

    .nav__list {
        flex-direction: column;
        gap: var(--space-10);
    }

    .nav__link {
        font-size: var(--text-title);
    }

    .nav__cta {
        font-size: var(--text-body);
        padding: var(--space-3) var(--space-10);
    }
}