/* === HEADER === */
header {
    background: var(--glass-bg);
    backdrop-filter: blur(20px);
    border-bottom: var(--border-1) solid var(--glass-border);
    position: sticky;
    z-index: 1;
    box-shadow: var(--shadow-card);
}

.header-name {
    font-size: var(--font-size-lg);
    font-weight: var(--font-weight-light);
    color: var(--text-secondary);
    margin-right: auto;
    opacity: 0.8;
    transition: var(--transition);
}

.header-name:hover {
    opacity: 1;
    color: var(--primary);
}

nav {
    max-width: 900px;
    margin: 0 auto;
    padding: var(--space-lg) var(--space-lg);
}

nav ul {
    list-style: none;
    display: flex;
    justify-content: center;
    gap: var(--space-xl);
}

nav li {
    position: relative;
}

nav a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: var(--font-size-lg);
    font-weight: var(--font-weight-medium);
    padding: var(--space-sm) var(--space-md);
    border-radius: var(--radius-lg);
    transition: var(--transition);
    position: relative;
    display: block;
}

nav a::before {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 50%;
    transform: translateX(-50%);
    width: 0;
    height: var(--border-2);
    background: var(--gradient-primary-secondary);
    border-radius: var(--radius-full);
    transition: var(--transition);
}

nav a:hover {
    color: var(--text-primary);
    background: var(--primary-opacity-10);
    transform: translateY(-2px);
}

nav a:hover::before {
    width: 80%;
}

nav a.active {
    color: var(--primary);
    background: var(--primary-opacity-20);
}

nav a.active::before {
    width: 80%;
}

#mobile-menu-toggle {
    display: none;
    background: none;
    border: none;
    color: var(--text-primary);
    font-size: var(--font-size-xl);
    padding: var(--space-sm);
    cursor: pointer;
    border-radius: var(--radius-md);
    transition: var(--transition);
}

/* === RESPONSIVE === */
@media (max-width: 768px) {
    nav {
        padding: var(--space-md) var(--space-lg);
        display: flex;
        justify-content: space-between;
        align-items: center;
    }

    #mobile-menu-toggle {
        display: block;
        position: relative;
        width: 40px;
        height: calc(4px * 3 + 11px * 2);
        cursor: pointer;
        background: none;
        border: none;
        z-index: 2;
    }

    .bar-top,
    .bar-middle,
    .bar-bottom {
        position: absolute;
        left: 0;
        right: 0;
        height: 4px;
        border-radius: 2px;
        background: var(--primary);
        transition: none 0.35s cubic-bezier(.5,-0.35,.35,1.5) 0s;
    }

    .bar-top {
        bottom: calc(50% + 11px + 2px);
        transition-property: bottom, transform;
        transition-delay: calc(0s + 0.35s), 0s;
    }

    .bar-middle {
        top: calc(50% - 2px);
        transition-property: opacity;
        transition-delay: calc(0s + 0.35s);
    }

    .bar-bottom {
        top: calc(50% + 11px + 2px);
        transition-property: top, transform;
        transition-delay: calc(0s + 0.35s), 0s;
    }

    #mobile-menu-toggle.open-menu .bar-top {
        bottom: calc(50% - 2px);
        transform: rotate(135deg);
        transition-delay: 0s, calc(0s + 0.35s);
    }

    #mobile-menu-toggle.open-menu .bar-middle {
        opacity: 0;
        transition-duration: 0s;
        transition-delay: calc(0s + 0.35s);
    }

    #mobile-menu-toggle.open-menu .bar-bottom {
        top: calc(50% - 2px);
        transform: rotate(225deg);
        transition-delay: 0s, calc(0s + 0.35s);
    }

    nav ul {
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: var(--glass-bg);
        backdrop-filter: blur(20px);
        border-top: var(--border-1) solid var(--glass-border);
        flex-direction: column;
        gap: 0;
        max-height: 0;
        overflow: hidden;
        transition: var(--transition);
    }

    nav ul.open {
        max-height: 300px;
    }

    nav li {
        border-bottom: var(--border-1) solid var(--glass-border);
    }

    nav li:last-child {
        border-bottom: none;
    }

    nav a {
        display: block;
        padding: var(--space-md) var(--space-lg);
        border-radius: 0;
    }

    nav a::before {
        display: none;
    }
}

@media (max-width: 480px) {
    nav {
        padding: var(--space-sm) var(--space-md);
    }
}

/* === ANIMACIONS === */
header {
    animation: slideInDown 0.6s ease-out;
}

@keyframes slideInDown {
    from {
        opacity: 0;
        transform: translateY(-20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}