/* 导航按钮样式 */
        .nav-buttons {
            display: flex;
            justify-content: center;
            gap: 20px;
            margin: 20px 0;
        }
        .nav-btn {
            background: linear-gradient(135deg, #3a8cff, #2c6e9e);
            color: white;
            border: none;
            padding: 12px 28px;
            border-radius: 40px;
            font-size: 1rem;
            font-weight: bold;
            cursor: pointer;
            transition: 0.1s;
            text-decoration: none;
            display: inline-block;
        }
        .nav-btn:hover {
            transform: scale(0.97);
            opacity: 0.9;
        }