/* 基础样式重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

/* 通用工具类 */
.hidden {
    display: none !important;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f8f9fa;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 导航栏样式 */
.navbar {
    background: #fff;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    transition: all 0.3s ease;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.nav-logo {
    display: flex;
    align-items: center;
    font-size: 1.5rem;
    font-weight: bold;
    color: #2c3e50;
    text-decoration: none;
}

.nav-logo i {
    margin-right: 10px;
    color: #3498db;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 30px;
}

.nav-menu a {
    text-decoration: none;
    color: #2c3e50;
    font-weight: 500;
    transition: color 0.3s ease;
    position: relative;
}

.nav-menu a:hover,
.nav-menu a.active {
    color: #3498db;
}

.nav-menu a.active::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    right: 0;
    height: 2px;
    background: #3498db;
}

.nav-auth {
    display: flex;
    gap: 15px;
}

.auth-link {
    display: flex;
    align-items: center;
    padding: 8px 16px;
    text-decoration: none;
    border-radius: 5px;
    font-weight: 500;
    transition: all 0.3s ease;
}

.login-link {
    color: #3498db;
    border: 1px solid #3498db;
}

.login-link:hover {
    background: #3498db;
    color: white;
}

.register-link {
    background: #3498db;
    color: white;
}

.register-link:hover {
    background: #2980b9;
}

.auth-link i {
    margin-right: 5px;
}

.nav-toggle {
    display: none;
    flex-direction: column;
    cursor: pointer;
}

.nav-toggle span {
    width: 25px;
    height: 3px;
    background: #2c3e50;
    margin: 3px 0;
    transition: 0.3s;
}

/* 主要内容区域 */
main {
    margin-top: 70px;
    min-height: calc(100vh - 70px);
}

/* 页脚样式 */
.footer {
    background: #2c3e50;
    color: #ecf0f1;
    padding: 50px 0 20px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    margin-bottom: 30px;
}

.footer-section h3 {
    color: #3498db;
    margin-bottom: 20px;
    font-size: 1.2rem;
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 10px;
}

.footer-section ul li a {
    color: #bdc3c7;
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-section ul li a:hover {
    color: #3498db;
}

.footer-section ul li i {
    margin-right: 10px;
    width: 15px;
}

.footer-logo {
    display: flex;
    align-items: center;
    font-size: 1.5rem;
    font-weight: bold;
    margin-bottom: 15px;
}

.footer-logo i {
    margin-right: 10px;
    color: #3498db;
}

.social-links {
    display: flex;
    gap: 15px;
    margin-top: 20px;
}

.social-links a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: #34495e;
    color: #ecf0f1;
    border-radius: 50%;
    text-decoration: none;
    transition: all 0.3s ease;
}

.social-links a:hover {
    background: #3498db;
    transform: translateY(-2px);
}

.footer-bottom {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid #34495e;
    color: #95a5a6;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background-color: #fff;
        width: 100%;
        text-align: center;
        transition: 0.3s;
        box-shadow: 0 10px 27px rgba(0,0,0,0.05);
        padding: 20px 0;
    }

    .nav-menu.active {
        left: 0;
    }

    .nav-toggle {
        display: flex;
    }

    .nav-auth {
        display: none;
    }

    .container {
        padding: 0 15px;
    }
}