/* 全局样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.6;
    color: #333;
    background: #f5f5f7;
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* 头部样式 */
.header {
    text-align: center;
    margin-bottom: 40px;
    color: #1d1d1f;
}

.header h1 {
    font-size: 2.5rem;
    margin-bottom: 10px;
    text-shadow: none;
}

.subtitle {
    font-size: 1.1rem;
    opacity: 0.7;
    margin-bottom: 0;
    color: #86868b;
}

/* 导航标签 */
.nav-tabs {
    display: flex;
    justify-content: center;
    margin-bottom: 30px;
    gap: 10px;
}

.tab-btn {
    padding: 12px 24px;
    border: none;
    background: rgba(255, 255, 255, 0.2);
    color: white;
    border-radius: 25px;
    cursor: pointer;
    font-size: 1rem;
    transition: all 0.3s ease;
    backdrop-filter: blur(10px);
}

.tab-btn:hover:not(:disabled) {
    background: rgba(255, 255, 255, 0.3);
    transform: translateY(-2px);
}

.tab-btn.active {
    background: white;
    color: #667eea;
    box-shadow: 0 4px 15px rgba(0,0,0,0.2);
}

.tab-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* 主内容区域 */
.main-content {
    flex: 1;
    display: flex;
    justify-content: center;
}

.tab-content {
    display: none;
    width: 100%;
    max-width: 800px;
}

.tab-content.active {
    display: block;
}

/* 功能卡片 */
.feature-card {
    background: white;
    border-radius: 20px;
    padding: 30px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.2);
    backdrop-filter: blur(10px);
}

.card-header {
    text-align: center;
    margin-bottom: 30px;
}

.card-header h2 {
    font-size: 1.8rem;
    margin-bottom: 10px;
    color: #333;
}

.card-header p {
    color: #666;
    font-size: 1rem;
}

/* 按钮样式 */
.btn {
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s ease;
    text-decoration: none;
    display: inline-block;
    text-align: center;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(102, 126, 234, 0.4);
}

.btn-secondary {
    background: #f8f9fa;
    color: #333;
    border: 2px solid #dee2e6;
}

.btn-secondary:hover {
    background: #e9ecef;
    transform: translateY(-1px);
}

.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

/* 底部 */
.footer {
    text-align: center;
    margin-top: 40px;
    color: rgba(255, 255, 255, 0.8);
    font-size: 0.9rem;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .container {
        padding: 15px;
    }
    
    .header h1 {
        font-size: 2rem;
    }
    
    .feature-card {
        padding: 20px;
    }
    
    .nav-tabs {
        flex-direction: column;
        align-items: center;
    }
    
    .tab-btn {
        width: 200px;
    }
}

@media (max-width: 480px) {
    .header h1 {
        font-size: 1.8rem;
    }
    
    .card-header h2 {
        font-size: 1.5rem;
    }
    
    .feature-card {
        padding: 15px;
    }
}