/* 页脚区域 */
        footer {
            background-color: #2a2a2a;
            color: white;
            padding: 50px 0 20px;
            margin-top: 50px;
        }
        
        .footer-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
            gap: 40px;
            margin-bottom: 40px;
        }
        
        .footer-column h3 {
            font-size: 1.2rem;
            margin-bottom: 20px;
            color: var(--primary);
        }
        
        .footer-links {
            list-style: none;
        }
        
        .footer-links li {
            margin-bottom: 10px;
        }
        
        .footer-links a {
            color: #ccc;
            text-decoration: none;
        }
        
        .social-links {
            display: flex;
            gap: 15px;
        }
        
        .social-links a {
            display: flex;
            align-items: center;
            justify-content: center;
            width: 40px;
            height: 40px;
            background-color: #3a3a3a;
            border-radius: 50%;
            color: white;
            text-decoration: none;
        }
        
        .copyright {
            text-align: center;
            padding-top: 20px;
            border-top: 1px solid #444;
            color: #ccc;
            font-size: 0.9rem;
        }