/* Header / Navbar */
.site-header {
    position: sticky;
    top: 0;
    z-index: 1000;
    backdrop-filter: blur(0.875rem);
    background: rgba(10, 10, 10, 0.82);
    border-bottom: 0.0625rem solid var(--color-border);
    transition:
        background-color 0.28s ease,
        border-color 0.28s ease,
        box-shadow 0.28s ease,
        backdrop-filter 0.28s ease;
}

.site-header::after {
    content: "";
    position: absolute;
    left: 0;
    right: 0;
    bottom: -0.0625rem;
    height: 0.0625rem;
    background: linear-gradient(90deg, transparent, rgba(var(--accent-soft-rgb), 0.18), transparent);
    opacity: 0.42;
    pointer-events: none;
}

.site-header.is-scrolled {
    backdrop-filter: blur(1.1rem);
    background: rgba(8, 8, 10, 0.94);
    border-bottom-color: rgba(255, 255, 255, 0.1);
    box-shadow: 0 0.8rem 2.6rem rgba(0, 0, 0, 0.22);
}

.navbar {
    min-height: 5rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1.5rem;
}

.brand {
    display: inline-flex;
    align-items: center;
    gap: 0.75rem;
    font-weight: 600;
    transition: transform var(--transition-fast);
}

.brand:hover {
    transform: translateY(-0.0625rem);
}

.brand-copy {
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: 0.08rem;
}

.brand-mark {
    position: relative;
    width: 2.5rem;
    height: 2.5rem;
    border: 0.0625rem solid rgba(var(--accent-rgb), 0.5);
    border-radius: 50%;
    display: grid;
    place-items: center;
    font-family: var(--font-heading);
    font-size: 1rem;
    color: var(--color-white);
    background:
        radial-gradient(circle at 30% 30%, rgba(255,255,255,0.08), transparent 45%),
        linear-gradient(135deg, rgba(var(--accent-rgb), 0.22), rgba(255, 255, 255, 0.02));
    box-shadow:
        inset 0 0 0.75rem rgba(255, 255, 255, 0.02),
        0 0 1.25rem rgba(var(--accent-rgb), 0.12);
    transition:
        transform 0.32s ease,
        border-color 0.32s ease,
        box-shadow 0.32s ease;
}

.brand-mark::after {
    content: "";
    position: absolute;
    inset: 0.22rem;
    border-radius: 50%;
    border: 0.0625rem solid rgba(255, 255, 255, 0.06);
    opacity: 0.9;
}

.brand-text {
    font-size: 0.98rem;
    line-height: 1.15;
    letter-spacing: 0.01em;
    color: var(--color-text);
}

.brand-meta {
    color: rgba(209, 209, 217, 0.54);
    font-size: 0.55rem;
    line-height: 1.2;
    letter-spacing: 0.18em;
    text-transform: uppercase;
}

.brand:hover .brand-mark {
    transform: rotate(-7deg) scale(1.03);
    border-color: rgba(var(--accent-soft-rgb), 0.62);
    box-shadow:
        inset 0 0 0.9rem rgba(255, 255, 255, 0.03),
        0 0 1.6rem rgba(var(--accent-rgb), 0.18);
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.nav-link {
    position: relative;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 2.75rem;
    padding: 0 0.95rem;
    border-radius: 999rem;
    color: var(--color-text-muted);
    font-size: 0.96rem;
    font-weight: 500;
    letter-spacing: 0.01em;
    transition:
        color var(--transition-fast),
        background-color var(--transition-fast),
        transform var(--transition-fast);
}

.nav-link::before {
    content: "";
    position: absolute;
    inset: 0;
    border-radius: inherit;
    background: linear-gradient(180deg, rgba(255,255,255,0.04), rgba(255,255,255,0.01));
    opacity: 0;
    transition: opacity var(--transition-fast);
}

.nav-link::after {
    content: "";
    position: absolute;
    left: 20%;
    bottom: 0.45rem;
    width: 60%;
    height: 0.0625rem;
    background: linear-gradient(90deg, transparent, rgba(var(--accent-soft-rgb), 0.95), transparent);
    transform: scaleX(0);
    transform-origin: center;
    transition: transform var(--transition-fast);
    opacity: 0.95;
}

.nav-link:hover {
    color: var(--color-text);
    background:
        linear-gradient(180deg, rgba(var(--accent-rgb), 0.1), rgba(255, 255, 255, 0.015));
    transform: translateY(-0.0625rem);
}

.nav-link:hover::before {
    opacity: 1;
}

.nav-link:hover::after {
    transform: scaleX(1);
}

.nav-link.is-active {
    color: var(--color-text);
    background:
        linear-gradient(180deg, rgba(var(--accent-rgb), 0.14), rgba(255, 255, 255, 0.02));
}

.nav-link.is-active::before {
    opacity: 1;
}

.nav-link.is-active::after {
    transform: scaleX(1);
}

.nav-cta {
    position: relative;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 2.95rem;
    padding: 0 1.35rem;
    margin-left: 0.55rem;
    border: 0.0625rem solid rgba(var(--accent-rgb), 0.42);
    border-radius: 999rem;
    color: var(--color-text);
    font-size: 0.96rem;
    font-weight: 600;
    background:
        linear-gradient(180deg, rgba(var(--accent-rgb), 0.18), rgba(var(--accent-deep-rgb), 0.08));
    box-shadow:
        inset 0 0 0.5rem rgba(255,255,255,0.015),
        0 0 1rem rgba(var(--accent-rgb), 0.08);
    transition:
        border-color var(--transition-fast),
        background var(--transition-fast),
        transform var(--transition-fast),
        box-shadow var(--transition-fast);
}

.nav-cta::after {
    content: "";
    position: absolute;
    inset: 0;
    border-radius: inherit;
    box-shadow: inset 0 0 0 0.0625rem rgba(255,255,255,0.02);
    pointer-events: none;
}

.nav-cta:hover {
    border-color: rgba(var(--accent-soft-rgb), 0.62);
    background:
        linear-gradient(180deg, rgba(var(--accent-soft-rgb), 0.26), rgba(var(--accent-rgb), 0.12));
    transform: translateY(-0.0625rem);
    box-shadow:
        inset 0 0 0.5rem rgba(255,255,255,0.02),
        0 0 1.4rem rgba(var(--accent-rgb), 0.14);
}

.brand:focus-visible,
.nav-link:focus-visible,
.nav-cta:focus-visible,
.nav-toggle:focus-visible {
    outline: none;
    box-shadow: 0 0 0 0.125rem rgba(255, 255, 255, 0.04), 0 0 0 0.25rem rgba(var(--accent-rgb), 0.34);
}

.nav-toggle {
    display: none;
    width: 3rem;
    height: 3rem;
    padding: 0;
    border: 0.0625rem solid var(--color-border);
    border-radius: 0.75rem;
    background: rgba(255,255,255,0.02);
    cursor: pointer;
    align-items: center;
    justify-content: center;
    flex-direction: column;
    gap: 0.3125rem;
    transition:
        border-color var(--transition-fast),
        background var(--transition-fast),
        transform var(--transition-fast);
}

.nav-toggle:hover {
    border-color: rgba(var(--accent-rgb), 0.35);
    background: rgba(255,255,255,0.04);
    transform: translateY(-0.0625rem);
}

.nav-toggle span {
    width: 1.125rem;
    height: 0.125rem;
    background-color: var(--color-white);
    display: block;
    transition: var(--transition-fast);
}

.nav-toggle[aria-expanded="true"] span:nth-child(1) {
    transform: translateY(0.4375rem) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] span:nth-child(2) {
    opacity: 0;
}

.nav-toggle[aria-expanded="true"] span:nth-child(3) {
    transform: translateY(-0.4375rem) rotate(-45deg);
}

/* Responsive */
@media (max-width: 64rem) {
    .nav-toggle {
        display: inline-flex;
    }

    .nav-menu {
        position: absolute;
        top: calc(100% + 0.0625rem);
        left: 5%;
        right: 5%;
        display: flex;
        flex-direction: column;
        align-items: stretch;
        gap: 0.5rem;
        padding: 1rem;
        background:
            radial-gradient(circle at top right, rgba(var(--accent-rgb), 0.12), transparent 28%),
            linear-gradient(180deg, rgba(18,18,20,0.985), rgba(12,12,14,0.985));
        border: 0.0625rem solid rgba(255, 255, 255, 0.08);
        border-radius: 1.125rem;
        box-shadow:
            0 1.25rem 2.5rem rgba(0, 0, 0, 0.28),
            0 0 1.8rem rgba(var(--accent-rgb), 0.06);
        opacity: 0;
        visibility: hidden;
        pointer-events: none;
        transform: translateY(-0.6rem) scale(0.985);
        transform-origin: top center;
        transition:
            opacity 0.22s ease,
            visibility 0.22s ease,
            transform 0.22s ease;
    }

    .nav-menu::before {
        content: "";
        position: absolute;
        inset: 0;
        border-radius: inherit;
        background:
            linear-gradient(180deg, rgba(255,255,255,0.03), transparent 22%);
        pointer-events: none;
    }

    .nav-menu.is-open {
        opacity: 1;
        visibility: visible;
        pointer-events: auto;
        transform: translateY(0) scale(1);
    }

    .nav-link,
    .nav-cta {
        width: 100%;
        justify-content: flex-start;
        min-height: 3rem;
        padding: 0 1rem;
        margin-left: 0;
        opacity: 0;
        transform: translateY(0.5rem);
        transition:
            opacity 0.28s ease,
            transform 0.28s ease,
            color var(--transition-fast),
            background-color var(--transition-fast),
            border-color var(--transition-fast),
            box-shadow var(--transition-fast);
    }

    .nav-menu.is-open .nav-link,
    .nav-menu.is-open .nav-cta {
        opacity: 1;
        transform: translateY(0);
    }

    .nav-link::after {
        left: 1rem;
        bottom: 0.55rem;
        width: 2.5rem;
        transform-origin: left;
    }

    .nav-cta {
        justify-content: center;
        margin-top: 0.35rem;
    }

    .nav-menu .nav-link:nth-child(1) {
        transition-delay: 0.03s;
    }

    .nav-menu .nav-link:nth-child(2) {
        transition-delay: 0.06s;
    }

    .nav-menu .nav-link:nth-child(3) {
        transition-delay: 0.09s;
    }

    .nav-menu .nav-link:nth-child(4) {
        transition-delay: 0.12s;
    }

    .nav-menu .nav-link:nth-child(5) {
        transition-delay: 0.15s;
    }

    .nav-menu .nav-cta {
        transition-delay: 0.18s;
    }
}

@media (max-width: 48rem) {
    .navbar {
        min-height: 4.5rem;
    }

    .brand-meta {
        font-size: 0.52rem;
        letter-spacing: 0.14em;
    }

    .brand-text {
        font-size: 0.9rem;
    }
}

@media (max-width: 30rem) {
    .brand {
        gap: 0.625rem;
    }

    .brand-copy {
        gap: 0.02rem;
    }

    .brand-mark {
        width: 2.25rem;
        height: 2.25rem;
        font-size: 0.92rem;
    }

    .brand-meta {
        display: none;
    }

    .brand-text {
        font-size: 0.85rem;
    }
}