/* ========== 管理后台样式 ========== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary: #6366f1;
    --primary-dark: #4f46e5;
    --primary-light: #8b5cf6;
    --secondary: #06b6d4;
    --success: #10b981;
    --danger: #ef4444;
    --warning: #f59e0b;
    --bg-dark: #0f172a;
    --bg-card: #1e293b;
    --bg-section: #1e293b;
    --text-primary: #f1f5f9;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    --border-color: #334155;
    --radius: 12px;
    --radius-lg: 16px;
    --shadow: 0 4px 6px -1px rgba(0,0,0,0.3);
    --transition: all 0.3s ease;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
}

.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 20px;
}

/* ========== 登录页面 ========== */
.login-page {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    padding: 20px;
}

.login-container {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    padding: 50px 40px;
    max-width: 420px;
    width: 100%;
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow);
}

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

.login-header i {
    font-size: 3rem;
    color: var(--primary);
    margin-bottom: 15px;
}

.login-header h1 {
    font-size: 1.8rem;
    font-weight: 700;
    margin-bottom: 8px;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.login-header p {
    color: var(--text-muted);
    font-size: 0.95rem;
}

.login-form {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.form-group label {
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-secondary);
}

.form-group input,
.form-group select,
.form-group textarea {
    padding: 12px 16px;
    background: var(--bg-dark);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    color: var(--text-primary);
    font-size: 0.95rem;
    transition: var(--transition);
    outline: none;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.2);
}

.form-group textarea {
    resize: vertical;
    min-height: 100px;
}

.btn {
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary), var(--primary-light));
    color: white;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(99, 102, 241, 0.4);
}

.btn-secondary {
    background: var(--border-color);
    color: var(--text-secondary);
}

.btn-secondary:hover {
    background: var(--text-muted);
    color: var(--text-primary);
}

.btn-block {
    width: 100%;
    justify-content: center;
    padding: 14px;
}

.btn-sm {
    padding: 8px 12px;
    font-size: 0.85rem;
}

.btn-edit {
    background: rgba(6, 182, 212, 0.15);
    color: var(--secondary);
}

.btn-edit:hover {
    background: var(--secondary);
    color: white;
}

.btn-delete {
    background: rgba(239, 68, 68, 0.15);
    color: var(--danger);
}

.btn-delete:hover {
    background: var(--danger);
    color: white;
}

.login-info {
    text-align: center;
    margin-top: 10px;
}

.login-info p {
    color: var(--text-muted);
    font-size: 0.85rem;
    margin-bottom: 10px;
}

.login-info a {
    color: var(--primary-light);
    font-size: 0.9rem;
}

.login-info a:hover {
    color: var(--primary);
}

/* ========== 提示信息 ========== */
.alert {
    padding: 14px 20px;
    border-radius: 8px;
    margin-bottom: 20px;
    font-size: 0.95rem;
    font-weight: 500;
}

.alert-success {
    background: rgba(16, 185, 129, 0.15);
    color: var(--success);
    border: 1px solid rgba(16, 185, 129, 0.3);
}

.alert-error {
    background: rgba(239, 68, 68, 0.15);
    color: var(--danger);
    border: 1px solid rgba(239, 68, 68, 0.3);
}

/* ========== 管理后台导航 ========== */
.admin-nav {
    background: rgba(15, 23, 42, 0.9);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 100;
}

.admin-nav .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 65px;
}

.admin-nav-brand {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.2rem;
    font-weight: 700;
}

.admin-nav-brand i {
    color: var(--primary);
    font-size: 1.5rem;
}

.admin-nav-links {
    display: flex;
    align-items: center;
    gap: 20px;
}

.admin-nav-links a {
    color: var(--text-secondary);
    font-size: 0.9rem;
    padding: 8px 16px;
    border-radius: 8px;
    transition: var(--transition);
}

.admin-nav-links a:hover,
.admin-nav-links a.active {
    background: rgba(99, 102, 241, 0.1);
    color: var(--text-primary);
}

.logout-btn {
    background: rgba(239, 68, 68, 0.1) !important;
    color: var(--danger) !important;
}

.logout-btn:hover {
    background: var(--danger) !important;
    color: white !important;
}

/* ========== 管理内容 ========== */
.admin-content {
    padding: 40px 0;
}

.admin-grid {
    display: grid;
    grid-template-columns: 1fr 350px;
    gap: 30px;
    align-items: start;
}

.admin-card {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    padding: 25px;
    border: 1px solid var(--border-color);
}

.admin-card-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 25px;
}

.admin-card-header h2 {
    font-size: 1.3rem;
    font-weight: 700;
    display: flex;
    align-items: center;
    gap: 10px;
}

.admin-card-header h2 i {
    color: var(--primary);
}

/* ========== 文章表单 ========== */
.article-form {
    background: var(--bg-dark);
    border-radius: var(--radius);
    padding: 25px;
    margin-bottom: 25px;
    border: 1px solid var(--border-color);
}

.article-form h3 {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 20px;
    color: var(--primary-light);
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 15px;
}

.form-actions {
    display: flex;
    gap: 15px;
    margin-top: 20px;
}

/* ========== 表格 ========== */
.admin-table {
    overflow-x: auto;
}

table {
    width: 100%;
    border-collapse: collapse;
}

thead th {
    text-align: left;
    padding: 12px 15px;
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-muted);
    border-bottom: 1px solid var(--border-color);
    white-space: nowrap;
}

tbody td {
    padding: 12px 15px;
    font-size: 0.9rem;
    border-bottom: 1px solid rgba(51, 65, 85, 0.5);
}

tbody tr:hover {
    background: rgba(99, 102, 241, 0.03);
}

.article-title-cell {
    max-width: 300px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    font-weight: 500;
}

.category-badge {
    padding: 4px 12px;
    background: rgba(99, 102, 241, 0.15);
    color: var(--primary-light);
    border-radius: 15px;
    font-size: 0.8rem;
    font-weight: 500;
}

.actions-cell {
    display: flex;
    gap: 8px;
}

/* ========== 分类管理 ========== */
.category-form {
    margin-bottom: 20px;
}

.input-group {
    display: flex;
    gap: 10px;
}

.input-group input {
    flex: 1;
}

.category-list {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.category-tag {
    padding: 6px 14px;
    background: rgba(99, 102, 241, 0.1);
    color: var(--primary-light);
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 500;
}

/* ========== 数据统计 ========== */
.stats-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 15px;
}

.stat-box {
    text-align: center;
    padding: 20px;
    background: var(--bg-dark);
    border-radius: var(--radius);
    border: 1px solid var(--border-color);
}

.stat-num {
    display: block;
    font-size: 1.8rem;
    font-weight: 800;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 5px;
}

.stat-desc {
    font-size: 0.85rem;
    color: var(--text-muted);
}

/* ========== 响应式 ========== */
@media (max-width: 1024px) {
    .admin-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .form-row {
        grid-template-columns: 1fr;
    }
    
    .admin-nav-links a span {
        display: none;
    }
    
    .stats-grid {
        grid-template-columns: 1fr 1fr;
    }
}

@media (max-width: 480px) {
    .login-container {
        padding: 30px 20px;
    }
    
    .admin-card-header {
        flex-direction: column;
        gap: 15px;
    }
    
    .actions-cell {
        flex-direction: column;
    }
}