/* ===== NAV (站点统一) ===== */
nav {
    background: linear-gradient(180deg, #1a1a1a 0%, #0f0f0f 100%);
    border-bottom: 2px solid var(--border);
    padding: 0.75rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.8);
}

nav::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    right: 0;
    height: 2px;
    background: linear-gradient(90deg, transparent 0%, var(--accent) 20%, var(--accent) 80%, transparent 100%);
    opacity: 0.6;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    text-decoration: none;
    color: var(--accent);
    font-family: 'Cinzel', serif;
    font-weight: 600;
    font-size: 1.2rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
}

.nav-brand img {
    width: 40px;
    height: 40px;
    border-radius: 4px;
    border: 1px solid var(--accent-dark);
    box-shadow: 0 0 10px rgba(74, 158, 255, 0.15);
}

.nav-links {
    display: flex;
    gap: 2rem;
}

.nav-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 500;
    transition: color 0.2s;
    padding: 0.5rem 0;
    position: relative;
    white-space: nowrap;
    flex-shrink: 0;
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent);
    transition: width 0.3s;
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--accent);
}

.nav-links a:hover::after,
.nav-links a.active::after {
    width: 100%;
}

@media (max-width: 600px) {
    nav {
        flex-direction: column;
        gap: 0.5rem;
        padding: 0.75rem 1rem;
        align-items: stretch;
    }

    .nav-links {
        gap: 1.25rem;
        overflow-x: auto;
        -webkit-overflow-scrolling: touch;
        scrollbar-width: none;
        padding-bottom: 0.25rem;
    }

    .nav-links::-webkit-scrollbar {
        display: none;
    }
}