/* CSS 自定义属性 - 配色方案 */
:root {
    /* 主色调 */
    --primary-color: #5B6AFF;
    --secondary-color: #8C54FF;
    --accent-color: #667EEA;
    
    /* 背景色 */
    --bg-primary: #FFFFFF;
    --bg-secondary: #F5F7FA;
    --bg-card: #FFFFFF;
    
    /* 文字颜色 */
    --text-primary: #333333;
    --text-secondary: #666666;
    --text-muted: #999999;
    
    /* 边框和分割线 */
    --border-color: #E5E7EB;
    --border-light: #F3F4F6;
    
    /* 阴影 */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.12);
    
    /* 间距 */
    --spacing-xs: 4px;
    --spacing-sm: 8px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;
    
    /* 圆角 */
    --radius-sm: 6px;
    --radius-md: 12px;
    --radius-lg: 16px;
    
    /* 动画 */
    --transition: all 0.3s ease;
    --transition-fast: all 0.15s ease;
}

/* 暗色主题 */
[data-theme="dark"] {
    --bg-primary: #1a1a1a;
    --bg-secondary: #2d2d2d;
    --bg-card: #262626;
    --text-primary: #ffffff;
    --text-secondary: #cccccc;
    --text-muted: #999999;
    --border-color: #404040;
    --border-light: #333333;
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.4);
}

/* 基础重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background-color: var(--bg-secondary);
    color: var(--text-primary);
    line-height: 1.6;
    transition: var(--transition);
}

/* 顶部导航栏 */
.top-nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: 60px;
    background-color: var(--bg-primary);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
    backdrop-filter: blur(10px);
}

.nav-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.logo {
    font-size: 24px;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border-radius: var(--radius-md);
}

.site-title {
    font-size: 20px;
    font-weight: 700;
    color: var(--text-primary);
}

/* 搜索框 */
.search-container {
    display: flex;
    align-items: center;
    position: relative;
    flex: 1;
    max-width: 400px;
    margin: 0 var(--spacing-xl);
}

.search-input {
    width: 100%;
    height: 40px;
    padding: 0 var(--spacing-md) 0 var(--spacing-lg);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background-color: var(--bg-secondary);
    color: var(--text-primary);
    font-size: 14px;
    transition: var(--transition);
}

.search-input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(91, 106, 255, 0.1);
}

.search-btn {
    position: absolute;
    right: var(--spacing-sm);
    background: none;
    border: none;
    font-size: 16px;
    cursor: pointer;
    padding: var(--spacing-xs);
    border-radius: var(--radius-sm);
    transition: var(--transition-fast);
}

.search-btn:hover {
    background-color: var(--border-light);
}

/* 导航操作区 */
.nav-actions {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.theme-toggle,
.menu-toggle {
    width: 40px;
    height: 40px;
    border: none;
    border-radius: var(--radius-md);
    background-color: var(--bg-secondary);
    color: var(--text-primary);
    font-size: 16px;
    cursor: pointer;
    transition: var(--transition-fast);
    display: flex;
    align-items: center;
    justify-content: center;
}

.theme-toggle:hover,
.menu-toggle:hover {
    background-color: var(--border-light);
    transform: scale(1.05);
}

.menu-toggle {
    display: none;
}

/* 主容器 */
.main-container {
    display: grid;
    grid-template-columns: 240px 1fr;
    margin-top: 60px;
    min-height: calc(100vh - 60px);
}

/* 左侧边栏 */
.sidebar {
    background-color: var(--bg-primary);
    border-right: 1px solid var(--border-color);
    padding: var(--spacing-lg);
    transition: var(--transition);
}

.nav-title {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-md);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.category-list {
    list-style: none;
}

.category-item {
    display: flex;
    align-items: center;
    padding: var(--spacing-sm) var(--spacing-md);
    margin-bottom: var(--spacing-xs);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: var(--transition-fast);
    position: relative;
}

.category-item:hover {
    background-color: var(--bg-secondary);
}

.category-item.active {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
}

.category-icon {
    font-size: 18px;
    margin-right: var(--spacing-sm);
    width: 24px;
    text-align: center;
}

.category-name {
    flex: 1;
    font-weight: 500;
}

.category-count {
    background-color: var(--border-light);
    color: var(--text-muted);
    padding: 2px 6px;
    border-radius: 10px;
    font-size: 12px;
    font-weight: 600;
    min-width: 20px;
    text-align: center;
}

.category-item.active .category-count {
    background-color: rgba(255, 255, 255, 0.2);
    color: white;
}

/* 主内容区 */
.main-content {
    padding: var(--spacing-lg);
    overflow-y: auto;
}

.content-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: var(--spacing-lg);
}

.content-header h2 {
    font-size: 28px;
    font-weight: 700;
    color: var(--text-primary);
}

.view-controls {
    display: flex;
    gap: var(--spacing-xs);
}

.view-btn {
    width: 36px;
    height: 36px;
    border: 1px solid var(--border-color);
    background-color: var(--bg-card);
    color: var(--text-secondary);
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: var(--transition-fast);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 14px;
}

.view-btn:hover {
    border-color: var(--primary-color);
    color: var(--primary-color);
}

.view-btn.active {
    background-color: var(--primary-color);
    border-color: var(--primary-color);
    color: white;
}

/* 工具网格 */
.tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

/* 工具卡片 */
.tool-card {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    transition: var(--transition);
    cursor: pointer;
    position: relative;
    overflow: hidden;
}

.tool-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    transform: scaleX(0);
    transition: var(--transition);
}

.tool-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-color);
}

.tool-card:hover::before {
    transform: scaleX(1);
}

.card-icon {
    width: 48px;
    height: 48px;
    border-radius: var(--radius-md);
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    margin-bottom: var(--spacing-md);
}

.card-title {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
    line-height: 1.4;
}

.card-description {
    color: var(--text-secondary);
    font-size: 14px;
    line-height: 1.5;
    margin-bottom: var(--spacing-md);
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.card-tags {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-xs);
    margin-bottom: var(--spacing-md);
}

.card-tag {
    background-color: var(--bg-secondary);
    color: var(--text-muted);
    padding: 4px 8px;
    border-radius: var(--radius-sm);
    font-size: 12px;
    font-weight: 500;
}

.card-action {
    width: 100%;
    height: 40px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    border: none;
    border-radius: var(--radius-md);
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition-fast);
}

.card-action:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(91, 106, 255, 0.3);
}

/* 骨架屏动画 */
.skeleton-card {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    animation: pulse 1.5s ease-in-out infinite;
}

.skeleton-icon {
    width: 48px;
    height: 48px;
    background-color: var(--border-light);
    border-radius: var(--radius-md);
    margin-bottom: var(--spacing-md);
}

.skeleton-title {
    height: 20px;
    background-color: var(--border-light);
    border-radius: var(--radius-sm);
    margin-bottom: var(--spacing-sm);
    width: 70%;
}

.skeleton-description {
    height: 14px;
    background-color: var(--border-light);
    border-radius: var(--radius-sm);
    margin-bottom: var(--spacing-xs);
}

.skeleton-description:last-of-type {
    width: 60%;
    margin-bottom: var(--spacing-md);
}

.skeleton-tags {
    display: flex;
    gap: var(--spacing-xs);
    margin-bottom: var(--spacing-md);
}

.skeleton-tags::before,
.skeleton-tags::after {
    content: '';
    height: 20px;
    width: 60px;
    background-color: var(--border-light);
    border-radius: var(--radius-sm);
}

.skeleton-button {
    height: 40px;
    background-color: var(--border-light);
    border-radius: var(--radius-md);
}

@keyframes pulse {
    0%, 100% {
        opacity: 1;
    }
    50% {
        opacity: 0.5;
    }
}

/* 空状态 */
.empty-state {
    text-align: center;
    padding: var(--spacing-xl) 0;
    color: var(--text-secondary);
}

.empty-icon {
    font-size: 48px;
    margin-bottom: var(--spacing-md);
    opacity: 0.5;
}

.empty-state h3 {
    font-size: 20px;
    margin-bottom: var(--spacing-sm);
    color: var(--text-primary);
}

/* 返回顶部按钮 */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    border: none;
    border-radius: 50%;
    font-size: 20px;
    cursor: pointer;
    transition: var(--transition);
    z-index: 1000;
    box-shadow: var(--shadow-md);
}

.back-to-top:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

/* 列表视图 */
.tools-grid.list-view {
    grid-template-columns: 1fr;
}

.tools-grid.list-view .tool-card {
    display: flex;
    align-items: center;
    gap: var(--spacing-lg);
    padding: var(--spacing-md) var(--spacing-lg);
}

.tools-grid.list-view .card-icon {
    margin-bottom: 0;
    flex-shrink: 0;
}

.tools-grid.list-view .card-content {
    flex: 1;
}

.tools-grid.list-view .card-title {
    margin-bottom: var(--spacing-xs);
}

.tools-grid.list-view .card-description {
    margin-bottom: var(--spacing-xs);
    -webkit-line-clamp: 1;
}

.tools-grid.list-view .card-tags {
    margin-bottom: 0;
}

.tools-grid.list-view .card-action {
    width: 120px;
    flex-shrink: 0;
}

/* 响应式设计 */
@media (max-width: 1024px) {
    .tools-grid {
        grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
        gap: var(--spacing-md);
    }
    
    .search-container {
        max-width: 300px;
        margin: 0 var(--spacing-md);
    }
}

@media (max-width: 768px) {
    .main-container {
        grid-template-columns: 1fr;
    }
    
    .sidebar {
        position: fixed;
        top: 60px;
        left: -240px;
        width: 240px;
        height: calc(100vh - 60px);
        z-index: 999;
        transition: var(--transition);
    }
    
    .sidebar.open {
        left: 0;
    }
    
    .menu-toggle {
        display: flex;
    }
    
    .nav-container {
        padding: 0 var(--spacing-sm);
    }
    
    .search-container {
        max-width: 200px;
        margin: 0 var(--spacing-sm);
    }
    
    .site-title {
        display: none;
    }
    
    .main-content {
        padding: var(--spacing-md);
    }
    
    .content-header {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--spacing-md);
    }
    
    .content-header h2 {
        font-size: 24px;
    }
    
    .tools-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-md);
    }
    
    .tools-grid.list-view .tool-card {
        flex-direction: column;
        align-items: flex-start;
        text-align: left;
    }
    
    .tools-grid.list-view .card-action {
        width: 100%;
    }
}

@media (max-width: 480px) {
    .search-container {
        max-width: 150px;
    }
    
    .search-input {
        font-size: 16px; /* 防止iOS缩放 */
    }
    
    .main-content {
        padding: var(--spacing-sm);
    }
    
    .tool-card {
        padding: var(--spacing-md);
    }
}

/* 高对比度和无障碍支持 */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

@media (prefers-contrast: high) {
    :root {
        --border-color: #000000;
        --text-secondary: #000000;
    }
    
    [data-theme="dark"] {
        --border-color: #ffffff;
        --text-secondary: #ffffff;
    }
}

/* 焦点样式 */
button:focus-visible,
input:focus-visible,
.category-item:focus-visible,
.tool-card:focus-visible {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

/* 打印样式 */
@media print {
    .top-nav,
    .sidebar,
    .back-to-top {
        display: none;
    }
    
    .main-container {
        grid-template-columns: 1fr;
        margin-top: 0;
    }
    
    .tool-card {
        break-inside: avoid;
        box-shadow: none;
        border: 1px solid #ccc;
    }
}