/* 导航菜单 */
.navbar {
    position: relative;
    z-index: 1000;
}
.nav-container {
    margin: 0 auto;
    display: flex;
    align-items: center;
}

/* 导航菜单样式 */
.nav-menu {
    display: flex;
    list-style: none;
    flex: 1;
}
.nav-item {
    position: relative;
}
.nav-link {
    color: white;
    text-decoration: none;
    padding: 12px 18px;
    display: block;
    transition: background-color 0.3s ease;
}
.nav-link:hover {
    background-color: rgba(255,255,255,0.1);
}
.nav-link.active {
    background-color: rgba(255,255,255,0.1);
}

/* 下拉菜单样式 */
.dropdown {
    position: absolute;
    top: 100%;
    left: 0;
    background: white;
    box-shadow: 0 8px 25px rgba(0,0,0,0.15);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: all 0.3s ease;
    z-index: 1001;
}

/* 下拉菜单显示状态 */
.dropdown.show {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}
.dropdown-item {
    min-width: 150px;
    text-align: center;
    padding: 12px 18px;
    color: #333;
    text-decoration: none;
    display: block;
    transition: background-color 0.2s ease;
    border-bottom: 1px solid #f0f0f0;
}
.dropdown-item:last-child {
    border-bottom: none;
}
.dropdown-item:hover {
    background-color: #f8f9fa;
    color: #667eea;
}