/* Menu chính */
header {
    position: fixed;
    width: 100%;
    background: rgba(30, 30, 47, 0.95);
    padding: 15px 20px;
    z-index: 100;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.2);
    display: flex;
    justify-content: center;
}

nav {
    max-width: 1100px;
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    font-size: 26px;
    font-weight: 700;
    color: #ff6b6b;
    letter-spacing: 1px;
    transition: transform 0.3s;
}

.logo:hover {
    transform: rotate(-5deg) scale(1.1);
}

.menu {
    list-style: none;
    display: flex;
    align-items: center;
}

.menu li {
    position: relative;
    margin-left: 30px;
}

.menu li a {
    text-decoration: none;
    color: white;
    font-weight: 500;
    padding: 5px 0;
    position: relative;
    transition: color 0.3s;
}

.menu li a::after {
    content: '';
    position: absolute;
    left: 0;
    bottom: -3px;
    width: 0%;
    height: 2px;
    background: linear-gradient(90deg, #ff6b6b, #6a5acd);
    transition: width 0.3s;
}

.menu li a:hover::after {
    width: 100%;
}

.menu li a:hover {
    color: #ff6b6b;
}

/* Dropdown */
.dropdown:hover .dropdown-menu {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.dropdown-menu {
    position: absolute;
    top: 35px;
    left: 0;
    background: rgba(30, 30, 47, 0.95);
    list-style: none;
    padding: 10px 0;
    border-radius: 8px;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: all 0.3s;
    min-width: 150px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
}

.dropdown-menu li {
    margin: 0;
}

.dropdown-menu li a {
    display: block;
    padding: 10px 20px;
    color: white;
    font-weight: 400;
}

.dropdown-menu li a:hover {
    background: #ff6b6b;
    color: white;
    border-radius: 5px;
}

/* Hamburger (cho mobile) */
.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
}

.hamburger span {
    height: 3px;
    width: 25px;
    background: white;
    margin: 4px 0;
    border-radius: 3px;
    transition: all 0.3s;
}

/* Responsive */
@media (max-width: 768px) {
    .menu {
        position: fixed;
        right: -100%;
        top: 60px;
        flex-direction: column;
        background: rgba(30, 30, 47, 0.95);
        width: 200px;
        transition: right 0.3s;
        border-radius: 8px 0 0 8px;
    }

    .menu.active {
        right: 0;
    }

    .menu li {
        margin: 15px 0;
    }

    .hamburger {
        display: flex;
    }

    .dropdown-menu {
        position: relative;
        top: 0;
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
        box-shadow: none;
    }
}