/* 全局样式 */
:root {
    --primary-color: #4361ee;
    --secondary-color: #3f37c9;
    --success-color: #4cc9f0;
    --danger-color: #f72585;
    --warning-color: #f8961e;
    --light-color: #f8f9fa;
    --dark-color: #212529;
    --gray-color: #6c757d;
    --border-radius: 12px;
    --box-shadow: 0 10px 30px rgba(0,0,0,0.1);
    --transition: all 0.3s ease;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    line-height: 1.6;
    color: var(--dark-color);
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
}

/* 容器 */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 导航栏 */
.navbar {
    background: rgba(255,255,255,0.95);
    backdrop-filter: blur(10px);
    box-shadow: var(--box-shadow);
    position: sticky;
    top: 0;
    z-index: 1000;
    padding: 1rem 0;
}

.navbar-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.logo {
    font-size: 1.8rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    text-decoration: none;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
    align-items: center;
}

.nav-menu a {
    text-decoration: none;
    color: var(--dark-color);
    font-weight: 500;
    transition: var(--transition);
    position: relative;
}

.nav-menu a:hover {
    color: var(--primary-color);
}

.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-color);
    transition: var(--transition);
}

.nav-menu a:hover::after {
    width: 100%;
}

/* 按钮样式 */
.btn {
    display: inline-block;
    padding: 0.8rem 1.8rem;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition);
    border: none;
    cursor: pointer;
    font-size: 1rem;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    box-shadow: 0 4px 15px rgba(67, 97, 238, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(67, 97, 238, 0.4);
}

.btn-outline {
    background: transparent;
    border: 2px solid var(--primary-color);
    color: var(--primary-color);
}

.btn-outline:hover {
    background: var(--primary-color);
    color: white;
}

/* 卡片样式 */
.card {
    background: white;
    border-radius: var(--border-radius);
    padding: 2rem;
    box-shadow: var(--box-shadow);
    transition: var(--transition);
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 40px rgba(0,0,0,0.15);
}

/* 文章网格 */
.article-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.article-card {
    background: white;
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: var(--box-shadow);
    transition: var(--transition);
    display: flex;
    flex-direction: column;
}

.article-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 40px rgba(0,0,0,0.15);
}

.article-image {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.article-content {
    padding: 1.5rem;
    flex: 1;
}

.article-title {
    font-size: 1.3rem;
    margin-bottom: 0.5rem;
    color: var(--dark-color);
    text-decoration: none;
    display: block;
}

.article-title:hover {
    color: var(--primary-color);
}

.article-meta {
    display: flex;
    gap: 1rem;
    color: var(--gray-color);
    font-size: 0.9rem;
    margin-bottom: 1rem;
}

.article-excerpt {
    color: var(--gray-color);
    margin-bottom: 1rem;
    line-height: 1.6;
}

/* 分类导航 */
.category-nav {
    background: white;
    border-radius: var(--border-radius);
    padding: 1.5rem;
    margin-bottom: 2rem;
    box-shadow: var(--box-shadow);
}

.category-list {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    list-style: none;
}

.category-item {
    position: relative;
}

.category-link {
    display: block;
    padding: 0.5rem 1.2rem;
    background: var(--light-color);
    border-radius: 50px;
    text-decoration: none;
    color: var(--dark-color);
    font-weight: 500;
    transition: var(--transition);
}

.category-link:hover,
.category-link.active {
    background: var(--primary-color);
    color: white;
}

.subcategory {
    position: absolute;
    top: 100%;
    left: 0;
    background: white;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    padding: 1rem;
    min-width: 200px;
    display: none;
    z-index: 100;
}

.category-item:hover .subcategory {
    display: block;
}

/* 表单样式 */
.form-container {
    max-width: 800px;
    margin: 2rem auto;
    background: white;
    border-radius: var(--border-radius);
    padding: 2rem;
    box-shadow: var(--box-shadow);
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: var(--dark-color);
}

.form-control {
    width: 100%;
    padding: 0.8rem 1rem;
    border: 2px solid #e9ecef;
    border-radius: 10px;
    font-size: 1rem;
    transition: var(--transition);
}

.form-control:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(67, 97, 238, 0.1);
}

/* 编辑器样式 */
.editor-toolbar {
    background: var(--light-color);
    border: 2px solid #e9ecef;
    border-bottom: none;
    border-radius: 10px 10px 0 0;
    padding: 0.8rem;
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.editor-btn {
    padding: 0.5rem 1rem;
    background: white;
    border: 1px solid #dee2e6;
    border-radius: 5px;
    cursor: pointer;
    transition: var(--transition);
}

.editor-btn:hover {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

.editor-content {
    min-height: 300px;
    border: 2px solid #e9ecef;
    border-top: none;
    border-radius: 0 0 10px 10px;
    padding: 1rem;
    font-size: 1rem;
    line-height: 1.6;
}

/* 管理表格 */
.table-responsive {
    overflow-x: auto;
}

.table {
    width: 100%;
    background: white;
    border-radius: var(--border-radius);
    border-collapse: collapse;
    overflow: hidden;
    box-shadow: var(--box-shadow);
}

.table th {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    padding: 1rem;
    text-align: left;
}

.table td {
    padding: 1rem;
    border-bottom: 1px solid #e9ecef;
}

.table tr:hover {
    background: #f8f9fa;
}

/* 状态标签 */
.status-badge {
    display: inline-block;
    padding: 0.3rem 0.8rem;
    border-radius: 50px;
    font-size: 0.85rem;
    font-weight: 600;
}

.status-pending {
    background: #fff3cd;
    color: #856404;
}

.status-approved {
    background: #d4edda;
    color: #155724;
}

.status-rejected {
    background: #f8d7da;
    color: #721c24;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .navbar-container {
        flex-direction: column;
        gap: 1rem;
    }
    
    .nav-menu {
        flex-wrap: wrap;
        justify-content: center;
        gap: 1rem;
    }
    
    .article-grid {
        grid-template-columns: 1fr;
    }
    
    .form-container {
        margin: 1rem;
        padding: 1.5rem;
    }
    
    .category-list {
        flex-direction: column;
    }
    
    .subcategory {
        position: static;
        display: none;
        margin-top: 0.5rem;
        margin-left: 1rem;
    }
    
    .category-item:hover .subcategory {
        display: block;
    }
}

/* 动画效果 */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in {
    animation: fadeIn 0.6s ease;
}

/* 加载动画 */
.loader {
    border: 3px solid #f3f3f3;
    border-radius: 50%;
    border-top: 3px solid var(--primary-color);
    width: 40px;
    height: 40px;
    animation: spin 1s linear infinite;
}

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