:root {
    --header-bg-color: #333;
    --footer-bg-color: #333;
    --text-color-light: white;
    --primary-color: #007BFF;
    --max-content-width: 1200px;
    --sidebar-width: 250px;
    --bg-color: #f0f0f0;
    --text-color: #333;
    --content-bg-color: white;
    --sidebar-bg-color: #27292b;
    --sidebar-text-color: #bdc3c7;
    --sidebar-hover-color: white;
    --table-header-bg: #333;
    --table-even-row: #f2f2f2;
    --article-bg: #f8f9fa;
    --article-hover-bg: #e9ecef;
    --code-bg: #f6f8fa;
    --inline-code-bg: rgba(27,31,35,0.05);
    --header-height: 60px;
    --section-spacing: 20px;
    --border-radius: 8px;
    --box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

body {
    font-family: Arial, sans-serif;
    background-color: var(--bg-color);
    margin: 0;
    padding: 0;
    line-height: 1.6;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

header {
    background-color: #3d3d3d;
    color: white;
    padding: 20px 0;
    margin-bottom: 20px;
    width: 100%;
    position: relative;
}

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

#theme-toggle {
    background: transparent;
    border: none;
    color: white;
    cursor: pointer;
    font-size: 1.2rem;
    padding: 8px;
    border-radius: 50%;
    transition: background-color 0.3s;
}

#theme-toggle:hover {
    background-color: rgba(255, 255, 255, 0.1);
}

.main-container {
    display: flex;
    flex: 1;
    width: 100%;
}

nav.sidebar {
    width: var(--sidebar-width);
    background-color: var(--sidebar-bg-color);
    padding: 20px 0;
    position: sticky;
    top: 0;
    height: 100vh;
    overflow-y: auto;
}

.sidebar-content {
    padding: 0 15px;
}

main {
    padding: 20px;
    max-width: var(--max-content-width);
    margin: 0 auto;
    flex: 1;
    width: 100%;
    box-sizing: border-box;
}

footer {
    background-color: var(--footer-bg-color);
    color: var(--text-color-light);
    text-align: center;
    padding: 20px 0;
    width: 100%;
}

.section {
    margin-bottom: var(--section-spacing);
    background-color: var(--content-bg-color);
    padding: 20px;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    flex: 1;
    min-width: 300px;
    margin: 10px;
}

.article-columns {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
}

.back-to-top {
    position: fixed;
    bottom: 20px;
    right: 20px;
    background-color: var(--header-bg-color);
    color: var(--text-color-light);
    width: 40px;
    height: 40px;
    text-align: center;
    line-height: 40px;
    border-radius: 50%;
    cursor: pointer;
    display: none;
    z-index: 99;
}

.article-list {
    list-style-type: none;
    padding: 0;
}

.article-item {
    padding: 10px 15px;
    margin-bottom: 8px;
    background-color: #f8f9fa;
    border-left: 4px solid var(--primary-color);
    transition: all 0.3s ease;
}

.article-item:hover {
    background-color: #e9ecef;
    transform: translateX(5px);
}

.article-item a {
    display: block;
    color: #555;  /* 更改为较深的灰色 */
    text-decoration: none;  /* 移除下划线 */
    transition: color 0.3s ease;
}

.article-item a:hover {
    color: #007BFF;  /* 悬停时变为蓝色 */
    text-decoration: none;  /* 悬停时也不显示下划线 */
    transform: translateX(5px);
}

.article-date {
    font-size: 0.9em;
    color: #6c757d;
    margin-top: 5px;
}

.nav-link {
    display: inline-block;
    padding: 6px 12px;
    background-color: #333;
    color: white;
    border-radius: 4px;
    text-decoration: none;
    min-width: 80px;
    text-align: center;
    font-size: 14px;
    margin: 5px;
    transition: background-color 0.3s;
}

.nav-link:hover {
    background-color: #555;
    text-decoration: none;
    color: white;
}

/* Mobile Responsiveness */
@media (max-width: 768px) {
    header {
        padding: 15px 0;
    }
    
    .header-content {
        padding: 0 15px;
        flex-wrap: wrap;
        justify-content: space-between;
    }
    
    header h1 {
        font-size: 1.5rem;
        margin: 0;
        max-width: 80%;
        word-break: break-word;
        overflow-wrap: break-word;
        word-wrap: break-word;
        hyphens: auto;
    }
    
    #theme-toggle {
        font-size: 1.1rem;
        padding: 8px;
        margin-left: 10px;
        flex-shrink: 0;
    }
    
    .main-container {
        flex-direction: column;
    }
    
    nav.sidebar {
        width: 100%;
        height: auto;
        position: relative;
    }
    
    main {
        padding: 15px;
        max-width: 100%;
    }
}

@media (max-width: 480px) {
    .header-content {
        flex-direction: column;
        align-items: flex-start;
        padding: 10px 15px;
    }
    
    header h1 {
        font-size: 1.2rem;
        width: 100%;
        max-width: 100%;
        margin-bottom: 10px;
        line-height: 1.3;
    }
    
    #theme-toggle {
        position: absolute;
        top: 10px;
        right: 15px;
    }
    
    .section {
        padding: 15px;
        margin: 8px 0;
    }
}