/* =============================================
   navbar.css — Sticky Navigation Bar
   ============================================= */

.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--navbar-height);
    z-index: 1000;
    background: rgba(10, 10, 12, 0.85);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--color-border);
    transition: background var(--transition-base), border-color var(--transition-base);
}

/* Scrolled state — slightly darker */
.navbar--scrolled {
    background: rgba(10, 10, 12, 0.95);
    border-bottom-color: var(--color-border-hover);
}

.navbar__container {
    max-width: var(--container-max);
    height: 100%;
    margin: 0 auto;
    padding: 0 var(--container-pad);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

/* ---- Logo ---- */
.navbar__logo {
    font-family: var(--font-mono);
    font-size: var(--text-xl);
    font-weight: 600;
    color: var(--color-text);
    letter-spacing: 0.04em;
    transition: color var(--transition-base);
}

.navbar__logo:hover {
    color: var(--color-blue);
}

.navbar__logo-bracket {
    color: var(--color-blue);
}

/* ---- Menu ---- */
.navbar__menu {
    display: flex;
    align-items: center;
    gap: var(--sp-8);
}

.navbar__link {
    font-size: var(--text-sm);
    font-weight: 500;
    color: var(--color-text-muted);
    letter-spacing: 0.02em;
    position: relative;
    padding-bottom: 2px;
    transition: color var(--transition-base);
}

.navbar__link::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 1px;
    background: var(--color-blue);
    transition: width var(--transition-base);
}

.navbar__link:hover,
.navbar__link.active {
    color: var(--color-text);
}

.navbar__link:hover::after,
.navbar__link.active::after {
    width: 100%;
}

/* ---- Mobile toggle ---- */
.navbar__toggle {
    display: none;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--sp-2);
    border-radius: var(--radius-sm);
}

.navbar__toggle-bar {
    display: block;
    width: 22px;
    height: 2px;
    background: var(--color-text-muted);
    border-radius: 2px;
    transition: transform var(--transition-base), opacity var(--transition-base), background var(--transition-base);
}

.navbar__toggle:hover .navbar__toggle-bar {
    background: var(--color-text);
}

/* Animate toggle → X */
.navbar__toggle[aria-expanded="true"] .navbar__toggle-bar:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
}

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

.navbar__toggle[aria-expanded="true"] .navbar__toggle-bar:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
}

/* ---- Responsive ---- */
@media (max-width: 640px) {
    .navbar__toggle {
        display: flex;
    }

    .navbar__menu {
        display: none;
        position: absolute;
        top: var(--navbar-height);
        left: 0;
        right: 0;
        flex-direction: column;
        align-items: flex-start;
        gap: 0;
        padding: var(--sp-4) var(--container-pad);
        background: rgba(13, 13, 16, 0.98);
        border-bottom: 1px solid var(--color-border);
    }

    .navbar__menu.open {
        display: flex;
    }

    .navbar__link {
        display: block;
        width: 100%;
        padding: var(--sp-3) 0;
        font-size: var(--text-base);
        border-bottom: 1px solid var(--color-border);
    }

    .navbar__link:last-child {
        border-bottom: none;
    }
}