/* 头部导航 */
header {
    background-color: white;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 100;
    transition: all 0.3s ease;
}

header.scrolled {
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.15);
    padding: 5px 0;
}

header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
    text-decoration: none;
}

.logo:hover {
    text-decoration: none;
}

.logo img {
    width: 40px;
    height: 40px;
    border-radius: 8px;
    transition: transform 0.3s ease;
}

.logo:hover img {
    transform: scale(1.05);
}

.logo-text {
    display: flex;
    flex-direction: column;
}

.logo-text h1 {
    color: #3273dc;
    font-size: 24px;
    font-weight: 700;
    margin: 0;
    line-height: 1.2;
}

.logo-text p {
    color: #666;
    font-size: 12px;
    margin: 0;
}

nav ul {
    display: flex;
}

nav ul li {
    margin-left: 25px;
}

nav ul li a {
    color: #444;
    font-weight: 500;
    padding: 10px 0;
    position: relative;
}

nav ul li a:after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    background-color: #3273dc;
    bottom: 0;
    left: 0;
    transition: width 0.3s ease;
}

nav ul li a:hover {
    color: #3273dc;
}

nav ul li a:hover:after {
    width: 100%;
}

/* 移动端菜单 */
.mobile-menu-toggle {
    display: none;
    background: none;
    border: none;
    color: #333;
    font-size: 24px;
    cursor: pointer;
}

/* 响应式设计 - 头部 */
@media (max-width: 768px) {
    header .container {
        flex-direction: row;
        flex-wrap: wrap;
    }
    
    .logo {
        margin-bottom: 0;
    }
    
    .mobile-menu-toggle {
        display: block;
    }
    
    nav {
        flex-basis: 100%;
        max-height: 0;
        overflow: hidden;
        transition: max-height 0.3s ease;
        margin-top: 20px;
    }
    
    nav.mobile-open {
        max-height: 300px;
    }
    
    nav ul {
        flex-direction: column;
        align-items: center;
    }
    
    nav ul li {
        margin: 10px 0;
    }
}