/* 基础样式重置和通用样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    background: #f8faff;
}

/* 通用容器类 */
.main-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 40px 20px;
}

/* 通用按钮样式 */
.btn {
    display: inline-block;
    padding: 12px 24px;
    border: none;
    border-radius: 25px;
    cursor: pointer;
    font-weight: 500;
    font-size: 14px;
    text-decoration: none;
    text-align: center;
    transition: all 0.3s ease;
    min-width: 80px;
}

.btn-primary {
    background: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
    color: white;
    box-shadow: 0 4px 15px rgba(79, 172, 254, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(79, 172, 254, 0.4);
}

.btn-secondary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.3);
}

.btn-secondary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(102, 126, 234, 0.4);
}

.btn-danger {
    background: linear-gradient(135deg, #ff6b6b 0%, #ee5a24 100%);
    color: white;
    box-shadow: 0 4px 15px rgba(255, 107, 107, 0.3);
}

.btn-danger:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(255, 107, 107, 0.4);
}

.full-width {
    width: 100%;
}

/* 通用卡片样式 */
.card {
    background: white;
    border-radius: 15px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
    padding: 30px;
    margin-bottom: 30px;
}

.card-title {
    font-size: 24px;
    font-weight: bold;
    margin-bottom: 20px;
    color: #2c3e50;
}

.card-subtitle {
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 15px;
    color: #34495e;
}

/* 通用网格布局 */
.grid-2 {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
}

.grid-3 {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.grid-4 {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 30px;
}

/* 通用间距类 */
.mb-10 { margin-bottom: 10px; }
.mb-15 { margin-bottom: 15px; }
.mb-20 { margin-bottom: 20px; }
.mb-30 { margin-bottom: 30px; }

.mt-10 { margin-top: 10px; }
.mt-15 { margin-top: 15px; }
.mt-20 { margin-top: 20px; }
.mt-30 { margin-top: 30px; }

/* 通用文本样式 */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.text-primary { color: #4facfe; }
.text-secondary { color: #667eea; }
.text-success { color: #2ecc71; }
.text-danger { color: #e74c3c; }
.text-warning { color: #f39c12; }
.text-muted { color: #7f8c8d; }

/* 加载动画 */
.loading {
    text-align: center;
    padding: 50px;
    color: #7f8c8d;
    font-size: 16px;
}

.loading::after {
    content: '';
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid #f3f3f3;
    border-top: 3px solid #4facfe;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-left: 10px;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* 响应式断点 */
@media (max-width: 1024px) {
    .grid-4 { grid-template-columns: repeat(2, 1fr); }
    .grid-3 { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
    .main-content {
        padding: 30px 15px;
    }
    
    .grid-4,
    .grid-3,
    .grid-2 {
        grid-template-columns: 1fr;
    }
    
    .card {
        padding: 20px;
        margin-bottom: 20px;
    }
}