/* 重置样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: "Microsoft YaHei", "PingFang SC", "Helvetica Neue", Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f5f5f5;
}

/* 主容器样式 */
.main-header {
            background: #2c3e50;
            box-shadow: 0 2px 10px rgba(0,0,0,0.1);
            position: sticky;
            top: 0;
            z-index: 1000;
        }

/* 导航栏激活状态 */
.nav-links a.active {
    background: rgba(255,255,255,0.2);
}
 .main-footer {
    background: #34495e;
    color: white;
    text-align: center;
    padding: 20px 20px;
    margin-top: 50px;
}

/* 响应式设计确保 */
@media (max-width: 768px) {
    .main-nav {
        flex-direction: column;
        height: auto;
        padding: 15px;
    }
    
    .nav-links {
        margin-top: 15px;
        flex-wrap: wrap;
        justify-content: center;
        gap: 15px;
    }
}

/* 导航栏 */
.main-nav {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 55px;
}

.nav-logo {
    font-size: 1.1rem;
    font-weight: bold;
    color: white;
    text-decoration: none;
}

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

.nav-links {
    display: flex;
    gap: 30px;
}

.nav-links a {
    font-size: 0.9rem;
    color: white;
    text-decoration: none;
    padding: 8px 16px;
    border-radius: 4px;
    transition: background-color 0.3s;
}

.nav-links a:hover {
    background: rgba(255,255,255,0.1);
}

/* 通用按钮样式 */
.btn-secondary {
    background: #95a5a6;
}

.btn-secondary:hover {
    background: #7f8c8d;
}

/* 卡片样式 */
.card {
    background: white;
    border-radius: 12px;
    padding: 30px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    transition: all 0.3s ease;
    border: 1px solid #e0e0e0;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(0,0,0,0.15);
}

/* 标签样式 */
.tag {
    display: inline-block;
    background: #ecf0f1;
    padding: 6px 12px;
    border-radius: 15px;
    font-size: 0.8rem;
    color: #2c3e50;
    margin: 2px 4px 2px 0;
}

.tag-primary {
    background: #3498db;
    color: white;
}

.tag-success {
    background: #2ecc71;
    color: white;
}

.tag-warning {
    background: #f39c12;
    color: white;
}

.tag-danger {
    background: #e74c3c;
    color: white;
}

/* 响应式工具类 */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.mt-1 { margin-top: 10px; }
.mt-2 { margin-top: 20px; }
.mt-3 { margin-top: 30px; }
.mb-1 { margin-bottom: 10px; }
.mb-2 { margin-bottom: 20px; }
.mb-3 { margin-bottom: 30px; }

.p-1 { padding: 10px; }
.p-2 { padding: 20px; }
.p-3 { padding: 30px; }

.d-flex { display: flex; }
.d-grid { display: grid; }
.d-none { display: none; }

.justify-center { justify-content: center; }
.align-center { align-items: center; }


@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes slideUp {
    from { 
        opacity: 0;
        transform: translateY(30px);
    }
    to { 
        opacity: 1;
        transform: translateY(0);
    }
}

/* 响应式设计 */
@media (max-width: 1200px) {
    .main-nav {
        padding: 0 15px;
    }
}

@media (max-width: 768px) {
    .main-nav {
        flex-direction: column;
        height: auto;
        padding: 15px;
    }
    
    .nav-links {
        margin-top: 15px;
        flex-wrap: wrap;
        justify-content: center;
        gap: 15px;
    }
    
    .nav-links a {
        padding: 6px 12px;
        font-size: 0.9rem;
    }
    
    .btn {
        padding: 10px 20px;
        font-size: 0.9rem;
    }
}

@media (max-width: 480px) {
    .main-nav {
        padding: 10px;
    }
    
    .nav-links {
        gap: 10px;
    }
    
    .nav-links a {
        padding: 4px 8px;
        font-size: 0.8rem;
    }
    
    .card {
        padding: 20px;
    }
}