/* 基础样式 */
:root {
    --primary-color: #4a90e2;
    --background-color: #ffffff;
    --text-color: #333333;
    --card-background: #f5f5f5;
    --nav-width: 250px;
}

/* 深色模式变量 */
.dark-mode {
    --background-color: #1a1a1a;
    --text-color: #ffffff;
    --card-background: #2d2d2d;
}

body {
    margin: 0;
    padding: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background-color: var(--background-color);
    color: var(--text-color);
    transition: background-color 0.3s, color 0.3s;
}

.page-container {
    display: flex;
    min-height: 100vh;
}

/* 左侧导航样式 */
.category-nav {
    width: var(--nav-width);
    background-color: var(--card-background);
    height: 100vh;
    position: fixed;
    left: 0;
    top: 0;
    overflow-y: auto;
    z-index: 1000;
    display: flex;
    flex-direction: column;
}

.nav-header {
    padding: 20px;
    border-bottom: 1px solid rgba(0,0,0,0.1);
}

.nav-header h2 {
    margin: 0;
    font-size: 1.2rem;
}

.menu-toggle {
    display: none;
    background: none;
    border: none;
    color: var(--text-color);
    font-size: 1.5rem;
    cursor: pointer;
    padding: 5px;
    margin-right: 10px;
}

.nav-list {
    list-style: none;
    padding: 0;
    margin: 0;
    flex: 1;
}

.nav-item {
    display: flex;
    align-items: center;
    padding: 15px 20px;
    color: var(--text-color);
    text-decoration: none;
    transition: background-color 0.3s;
}

.nav-item:hover {
    background-color: rgba(0,0,0,0.1);
}

.nav-item i {
    margin-right: 10px;
    width: 20px;
    text-align: center;
}

/* 主内容区域样式 */
.main-content {
    flex: 1;
    margin-left: var(--nav-width);
    padding: 20px;
}

/* 头部搜索栏样式 */
.header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 30px;
    padding: 20px;
    background-color: var(--card-background);
    border-radius: 8px;
}

.search-container {
    display: flex;
    gap: 10px;
    flex: 1;
    margin-right: 20px;
}

.search-container select,
.search-container input,
.search-container button {
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: 4px;
    background-color: var(--background-color);
    color: var(--text-color);
}

.search-container input {
    flex: 1;
}

.theme-switch button {
    background: none;
    border: none;
    color: var(--text-color);
    font-size: 1.2rem;
    cursor: pointer;
    padding: 5px;
}

/* 资源卡片样式 */
.category-section {
    margin-bottom: 40px;
}

.category-section h2 {
    margin-bottom: 20px;
    padding-bottom: 10px;
    border-bottom: 2px solid var(--primary-color);
}

.category-section h2 i {
    margin-right: 10px;
}

.resource-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 20px;
}

.resource-card {
    display: flex;
    flex-direction: column;
    padding: 20px;
    border-radius: 8px;
    text-decoration: none;
    color: white;
    background-color: #2c3e50;
    transition: transform 0.2s, box-shadow 0.2s;
}

.resource-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 15px rgba(0,0,0,0.3);
    background-color: #34495e;
}

.resource-card i {
    font-size: 2rem;
    margin-bottom: 15px;
    color: var(--primary-color);
}

.resource-card h3 {
    margin: 0 0 10px 0;
    font-size: 1.2rem;
    color: white;
}

.resource-card p {
    margin: 0;
    opacity: 0.8;
    font-size: 0.9rem;
    color: rgba(255, 255, 255, 0.8);
}

/* 标签样式 */
.tags {
    display: flex;
    flex-wrap: wrap;
    gap: 5px;
    margin-top: 10px;
}

.tag {
    padding: 2px 8px;
    background-color: rgba(255, 255, 255, 0.1);
    border-radius: 12px;
    font-size: 12px;
    color: rgba(255, 255, 255, 0.9);
}

/* 响应式布局 */
@media (max-width: 768px) {
    :root {
        --nav-width: 250px;
    }

    .page-container {
        position: relative;
    }

    .category-nav {
        box-shadow: 2px 0 5px rgba(0,0,0,0.1);
    }

    .main-content {
        margin-left: 0;
        width: 100%;
    }

    .header {
        flex-direction: column;
        align-items: stretch;
    }

    .search-container {
        margin-right: 0;
        margin-bottom: 10px;
    }

    .theme-switch {
        text-align: right;
    }
} 

/* 管理后台链接样式 */
.admin-link {
    padding: 15px 0;
    border-top: 1px solid rgba(0,0,0,0.1);
    margin-top: auto;
}

.admin-link .nav-item {
    color: var(--text-color);
    opacity: 0.8;
    transition: opacity 0.3s;
}

.admin-link .nav-item:hover {
    opacity: 1;
    background-color: rgba(0,0,0,0.1);
}

/* 深色模式下的边框颜色 */
.dark-mode .admin-link {
    border-top-color: rgba(255,255,255,0.1);
}