.site-header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 100;
    padding: 1.6rem 2rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: transparent;
    transition: background 0.4s ease, backdrop-filter 0.4s ease;
    box-sizing: border-box;
}



.header-logo {
    font-family: var(--font);
    font-size: 0.8rem;
    letter-spacing: 0.35em;
    color: var(--primary-color);
    text-decoration: none;
    text-transform: lowercase;
    transition: opacity 0.2s ease;
}

.header-logo:hover {
    opacity: 0.6;
}

.main-nav ul {
    list-style: none;
    display: flex;
    gap: 2.8rem;
}

.main-nav a {
    font-family: var(--font);
    font-size: 0.72rem;
    letter-spacing: 0.3em;

    color: var(--primary-color);
    text-decoration: none;
    text-transform: lowercase;
    position: relative;
    padding-bottom: 2px;
    transition: opacity 0.2s ease;
}

.main-nav a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 1px;
    background: var(--primary-color);
    transition: width 0.3s ease;
}

.main-nav a:hover::after {
    width: 100%;
}

.main-nav a:hover {
    opacity: 0.65;
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
    z-index: 110;
    color: var(--primary-color);
}

.nav-toggle span {
    display: block;
    width: 22px;
    height: 1.5px;
    background: var(--primary-color);
    transition: transform 0.35s ease, opacity 0.35s ease;
    transform-origin: center;
}

.nav-toggle.open span:nth-child(1) { transform: translateY(6.5px) rotate(45deg); }
.nav-toggle.open span:nth-child(2) { opacity: 0; transform: scaleX(0); }
.nav-toggle.open span:nth-child(3) { transform: translateY(-6.5px) rotate(-45deg); }

.nav-overlay {
    position: fixed;
    inset: 0;
    z-index: 105;
    background: var(--white-color);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    transform: translateY(-100%);
    transition: transform 0.5s cubic-bezier(0.76, 0, 0.24, 1);
    pointer-events: none;
}

.nav-overlay.open {
    transform: translateY(0);
    pointer-events: all;
}

/* Titel in de overlay */
.overlay-title {
    font-family: var(--font);
    font-size: 1.4rem;
    letter-spacing: 0.4em;
    color: var(--primary-color);
    text-transform: uppercase;
    margin-bottom: 3rem;
    opacity: 0;
    transition: opacity 0.4s ease 0.1s;
}

.nav-overlay.open .overlay-title {
    opacity: 1;
}

.overlay-nav ul {
    list-style: none;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 2.8rem;
}

.overlay-nav a {
    font-family: var(--font);
    font-size: clamp(1.1rem, 5.5vw, 1.6rem);
    letter-spacing: 0.3em;
    color: var(--primary-color);
    text-decoration: none;
    text-transform: lowercase;
    opacity: 0;
    transform: translateY(16px);
    transition:
            opacity 0.4s ease calc(var(--i, 0) * 0.08s + 0.15s),
            transform 0.4s ease calc(var(--i, 0) * 0.08s + 0.15s),
            color 0.2s ease;
}

.nav-overlay.open .overlay-nav a {
    opacity: 1;
    transform: translateY(0);
}

.overlay-nav a:hover {
    color: var(--secondary-color);
}

.overlay-nav li {
    position: relative;
}

.overlay-nav li:not(:last-child)::after {
    content: '';
    position: absolute;
    bottom: -1.4rem;
    left: 50%;
    transform: translateX(-50%);
    width: 1px;
    height: 1px;
    background: var(--semi-white-color);
}

.nav-overlay-close {
    position: absolute;
    top: 1.2rem;
    right: 1.5rem;
    width: 32px;
    height: 32px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: opacity 0.3s ease 0.3s;
}

.nav-overlay.open .nav-overlay-close {
    opacity: 1;
}

.nav-overlay-close span {
    position: absolute;
    width: 22px;
    height: 1.5px;
    background: var(--primary-color);
    transition: opacity 0.2s ease;
}

.nav-overlay-close span:nth-child(1) { transform: rotate(45deg); }
.nav-overlay-close span:nth-child(2) { transform: rotate(-45deg); }

.nav-overlay-close:hover span {
    opacity: 0.5;
}

/* ── Responsive ──────────────────────────────────────────── */
@media (max-width: 600px) {
    .site-header {
        padding: 1.2rem 1.5rem;
        background: transparent !important;
        backdrop-filter: none !important;
        -webkit-backdrop-filter: none !important;
    }

    .header-logo {
        color: var(--semi-white-color);
    }

    .main-nav {
        display: none;
    }

    .nav-toggle {
        display: flex;
    }

    .nav-toggle span {
        background: var(--semi-white-color);
    }
}