/* Global styles */
:root {
    /* Colors */
    --bg-color: #f4f7f9;
    --text-color: #333;
    --text-color-secondary: #7f8c8d;
    --text-color-muted: #95a5a6;
    
    /* Sidebar */
    --sidebar-bg: #2c3e50;
    --sidebar-text: #ecf0f1;
    --sidebar-hover: #3498db;
    --sidebar-active-bg: #34495e;
    
    /* UI Elements */
    --card-bg: white;
    --card-shadow: rgba(0, 0, 0, 0.05);
    --border-color: #eee;
    --border-radius-sm: 4px;
    --border-radius-md: 8px;
    --border-radius-lg: 12px;
    --border-radius-circle: 50%;
    
    /* Links */
    --link-color: #3498db;
    --link-hover: #2980b9;
    
    /* Search */
    --search-bg: #34495e;
    --search-text: #ecf0f1;
    --search-placeholder: #bdc3c7;
    --search-focus-outline: #3498db;
    
    /* Misc */
    --highlight-bg: rgba(52, 152, 219, 0.3);
    --topic-item-bg: #f8f9fa;
    --topic-item-hover: #ecf0f1;
    
    /* Spacing */
    --spacing-xs: 4px;
    --spacing-sm: 8px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;
    
    /* Typography */
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-md: 1rem;
    --font-size-lg: 1.25rem;
    --font-size-xl: 1.5rem;
    --font-size-xxl: 2rem;
    
    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-medium: 0.3s ease;
    --transition-slow: 0.5s ease;
}

/* Enable smooth scrolling for all browsers */
html {
    scroll-behavior: smooth;
    /* Prevent content jumps when scrollbar appears/disappears */
    scrollbar-gutter: stable;
    /* Improve rendering performance on mobile */
    -webkit-text-size-adjust: 100%;
    -webkit-tap-highlight-color: transparent;
}

body.dark-mode {
    /* Colors */
    --bg-color: #121212;
    --text-color: #e0e0e0;
    --text-color-secondary: #b0bec5;
    --text-color-muted: #78909c;
    
    /* Sidebar */
    --sidebar-bg: #1a1a1a;
    --sidebar-text: #f5f5f5;
    --sidebar-hover: #64b5f6;
    --sidebar-active-bg: #2a2a2a;
    
    /* UI Elements */
    --card-bg: #1e1e1e;
    --card-shadow: rgba(0, 0, 0, 0.2);
    --border-color: #333;
    --secondary-text: #b0bec5;
    --link-color: #64b5f6;
    --link-hover: #90caf9;
    --search-bg: #2a2a2a;
    --search-text: #f5f5f5;
    --search-placeholder: #b0bec5;
    --search-focus-outline: #64b5f6;
    --highlight-bg: rgba(100, 181, 246, 0.3);
    --topic-item-bg: #2a2a2a;
    --topic-item-hover: #333333;
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--bg-color);
    transition: background-color var(--transition-medium), color var(--transition-medium);
}

/* Accessibility Styles */
.skip-link {
    position: absolute;
    top: -40px;
    left: 0;
    background-color: var(--link-color);
    color: white;
    padding: var(--spacing-sm) var(--spacing-md);
    z-index: 1000;
    transition: top var(--transition-medium);
    text-decoration: none;
    font-weight: 500;
    border-radius: 0 0 var(--border-radius-sm) 0;
}

.skip-link:focus {
    top: 0;
}

/* Visible focus indicators for keyboard navigation */
body.keyboard-nav :focus {
    outline: 3px solid var(--link-color) !important;
    outline-offset: 3px;
}

/* Improve color contrast in dark mode */
body.dark-mode .article-tag {
    color: #d8d8d8;
}

/* Links */
a {
    color: var(--link-color);
    text-decoration: none;
    transition: color var(--transition-fast);
}

a:hover, a:focus {
    color: var(--link-hover);
    text-decoration: underline;
}

/* Read status indicator for articles */
.article-link.read {
    position: relative;
}

.article-link.read::after {
    content: '✓';
    display: inline-block;
    margin-left: var(--spacing-xs);
    font-size: var(--font-size-xs);
    color: var(--link-color);
    opacity: 0.7;
}

/* Articles list read indicator */
.article-list-link.read,
.read-more-link.read {
    position: relative;
}

.article-list-link.read::after {
    content: '✓ Read';
    display: inline-block;
    margin-left: var(--spacing-xs);
    font-size: var(--font-size-xs);
    color: var(--text-color-muted);
    font-weight: normal;
}

/* Text selection */
::selection {
    background-color: var(--highlight-bg);
    color: var(--text-color);
}

/* Theme toggle styles */
.theme-toggle-container {
    position: fixed;
    bottom: var(--spacing-md);
    right: var(--spacing-md); /* Moved to bottom right */
    z-index: 1010;
    background-color: var(--card-bg);
    border-radius: var(--border-radius-circle);
    box-shadow: 0 2px 8px var(--card-shadow);
    padding: var(--spacing-xs);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

/* No need for this adjustment when positioned in the right corner */
@media (min-width: 1024px) {
    .theme-toggle-container {
        bottom: var(--spacing-md);
        right: var(--spacing-md);
    }
}

.theme-toggle-container:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px var(--card-shadow);
}

.theme-toggle {
    background: none;
    border: none;
    color: var(--text-color);
    font-size: var(--font-size-lg);
    cursor: pointer;
    transition: color var(--transition-fast), transform var(--transition-fast);
    padding: var(--spacing-sm);
    width: 40px;
    height: 40px;
    border-radius: var(--border-radius-circle);
    display: flex;
    align-items: center;
    justify-content: center;
}

.theme-toggle:hover {
    color: var(--link-color);
    transform: rotate(15deg);
}

.theme-toggle:focus-visible {
    outline: 2px solid var(--link-color);
    outline-offset: 2px;
}

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

/* Sidebar styles */
.sidebar {
    width: 250px;
    background-color: var(--sidebar-bg);
    color: var(--sidebar-text);
    padding: 0;
    position: fixed;
    height: 100%;
    display: flex;
    flex-direction: column;
    transition: all var(--transition-medium);
    scrollbar-width: thin;
    scrollbar-color: var(--sidebar-hover) var(--sidebar-bg);
    overflow: hidden; /* Prevent entire sidebar from scrolling */
}

.sidebar::-webkit-scrollbar {
    width: 8px;
}

.sidebar::-webkit-scrollbar-track {
    background: var(--sidebar-bg);
}

.sidebar::-webkit-scrollbar-thumb {
    background-color: var(--sidebar-active-bg);
    border-radius: var(--border-radius-md);
}

.sidebar-header {
    padding: 0 var(--spacing-lg);
    border-bottom: 2px solid var(--sidebar-active-bg);
    background: linear-gradient(135deg, var(--sidebar-bg) 0%, var(--sidebar-active-bg) 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 0;
    flex-shrink: 0; /* Prevent header from shrinking */
    position: sticky;
    top: 0;
    z-index: 10;
}

.brand-container {
    width: 100%;
    display: flex;
    justify-content: center;
}

.brand-link {
    color: var(--sidebar-text);
    text-decoration: none;
    transition: all var(--transition-fast);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm);
    border-radius: var(--border-radius-sm);
    font-weight: 700;
    letter-spacing: 1px;
    font-size: var(--font-size-lg);
}

.brand-link:hover {
    color: var(--sidebar-hover);
    background-color: rgba(255, 255, 255, 0.1);
    transform: translateY(-1px);
}

.brand-text {
    user-select: none;
}

.sidebar-icon {
    width: 28px;
    height: 28px;
    border-radius: var(--border-radius-sm);
    transition: transform var(--transition-fast);
    flex-shrink: 0;
}

.brand-link:hover .sidebar-icon {
    transform: scale(1.1) rotate(5deg);
}

/* Menu styles */
.sidebar-menu {
    padding: var(--spacing-sm) 0;
    flex: 1; /* Take remaining space */
    overflow-y: auto; /* Enable scrolling for articles only */
    scrollbar-width: thin;
    scrollbar-color: var(--sidebar-hover) var(--sidebar-bg);
    position: relative;
}

.sidebar-menu::before {
    content: '';
    position: sticky;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--sidebar-active-bg), transparent);
    z-index: 1;
}

.sidebar-menu::-webkit-scrollbar {
    width: 8px;
}

.sidebar-menu::-webkit-scrollbar-track {
    background: var(--sidebar-bg);
}

.sidebar-menu::-webkit-scrollbar-thumb {
    background-color: var(--sidebar-active-bg);
    border-radius: var(--border-radius-md);
}

.sidebar-menu ul {
    list-style-type: none;
}

.sidebar-menu li {
    padding: 0;
    border-left: 3px solid transparent;
    transition: all 0.2s ease;
}

.sidebar-menu li:hover {
    background-color: var(--sidebar-active-bg);
    border-left: 3px solid var(--sidebar-hover);
    cursor: pointer;
}

.sidebar-menu li.active {
    background-color: var(--sidebar-active-bg);
    border-left: 3px solid var(--sidebar-hover);
}

.sidebar-menu a {
    color: var(--sidebar-text);
    text-decoration: none;
    display: block;
    font-size: 1rem;
    padding: 10px 20px;
    transition: color 0.2s ease;
}

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

/* Navigation styles */
.sidebar-navigation {
    padding: var(--spacing-md) 0;
    border-bottom: 1px solid var(--sidebar-active-bg);
    margin-bottom: 0;
    flex-shrink: 0; /* Prevent navigation from shrinking */
    background-color: rgba(0, 0, 0, 0.1);
}

.sidebar-navigation h3 {
    color: var(--sidebar-text);
    font-size: var(--font-size-md);
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
    padding: 0 var(--spacing-lg);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

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

.nav-list li {
    border-left: 3px solid transparent;
    transition: all var(--transition-fast);
    margin-bottom: 2px;
}

.nav-list li:hover {
    background-color: var(--sidebar-active-bg);
    border-left: 3px solid var(--sidebar-hover);
}

.nav-list a {
    color: var(--sidebar-text);
    text-decoration: none;
    display: flex;
    align-items: center;
    padding: var(--spacing-sm) var(--spacing-lg);
    font-size: var(--font-size-sm);
    font-weight: 500;
    transition: all var(--transition-fast);
    gap: var(--spacing-sm);
}

.nav-list a:hover {
    color: var(--sidebar-hover);
    background-color: rgba(255, 255, 255, 0.05);
}

.nav-list a i {
    width: 16px;
    text-align: center;
    font-size: var(--font-size-md);
}

.nav-list a span {
    flex: 1;
}

/* Main content styles */
.content {
    flex: 1;
    margin-left: 250px;
    padding: 30px;
    transition: all 0.3s ease;
}

#article-container {
    background-color: var(--card-bg);
    padding: 30px;
    border-radius: 5px;
    box-shadow: 0 2px 10px var(--card-shadow);
    min-height: calc(100vh - 60px);
}

.article {
    max-width: 800px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    min-height: 100%;
}

.article-header {
    margin-bottom: 30px;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 15px;
    order: 1;
}

.article-content {
    flex: 1;
    order: 2;
    margin-bottom: var(--spacing-lg);
}

.article-title {
    font-size: 2.2rem;
    margin-bottom: 10px;
    color: var(--text-color);
}

.article-meta {
    display: flex;
    color: var(--secondary-text);
    font-size: 0.9rem;
    margin-bottom: 10px;
}

.article-date {
    margin-right: 15px;
}

.article-content {
    font-size: 1.1rem;
    line-height: 1.8;
}

.article-content p {
    margin-bottom: 20px;
}

.article-content h2 {
    margin: 30px 0 15px;
    font-size: 1.8rem;
    color: var(--text-color);
}

.article-content h3 {
    margin: 25px 0 15px;
    font-size: 1.5rem;
    color: var(--text-color);
}

.article-content ul, .article-content ol {
    margin-bottom: 20px;
    padding-left: 25px;
}

.article-content img {
    max-width: 100%;
    height: auto;
    margin: 30px 0;
    display: block;
}

.article-content img:first-child {
    margin-top: 0;
}

/* Remove top margin from any first child element in article content */
.article-content > *:first-child {
    margin-top: 0 !important;
}

/* Article image specific styling */
.article-content .article-image {
    max-width: 100%;
    width: 80%;
    height: auto;
    margin: 30px auto;
    display: block;
    border-radius: 12px;
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.15);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.article-content .article-image:hover {
    transform: scale(1.02);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.2);
}

/* Logo styling for article headers */
.article-content .article-image[alt*="Logo"] {
    max-width: 400px;
    width: 60%;
    margin: 30px auto;
}

/* Article content specific styles */
.article-content {
    padding: 0 0 var(--spacing-md) 0;
}

.article-content h2 {
    font-size: var(--font-size-xl);
    margin-bottom: var(--spacing-md);
    position: relative;
    display: inline-block;
}

.article-content h2::after {
    content: '';
    position: absolute;
    width: 100%;
    height: 2px;
    bottom: -5px;
    left: 0;
    background: var(--link-color);
    border-radius: var(--border-radius-sm);
}

.article-content h3 {
    font-size: var(--font-size-lg);
    margin-bottom: var(--spacing-md);
    position: relative;
    display: inline-block;
}

.article-content h3::after {
    content: '';
    position: absolute;
    width: 100%;
    height: 2px;
    bottom: -5px;
    left: 0;
    background: var(--link-color);
    border-radius: var(--border-radius-sm);
}

.article-content blockquote {
    border-left: 4px solid var(--link-color);
    padding-left: var(--spacing-md);
    margin: 0;
    color: var(--text-color);
    font-style: italic;
}

.article-content pre {
    background: #f8f9fa;
    padding: var(--spacing-md);
    border-radius: var(--border-radius-md);
    overflow-x: auto;
    margin: 20px 0;
}

.article-content code {
    background: rgba(52, 152, 219, 0.1);
    padding: 2px 4px;
    border-radius: 4px;
    font-size: 0.95rem;
}

/* Table styles */
.article-content table {
    width: 100%;
    border-collapse: collapse;
    margin: 20px 0;
}

.article-content th, .article-content td {
    padding: 12px 15px;
    border: 1px solid var(--border-color);
    text-align: left;
}

.article-content th {
    background-color: var(--topic-item-bg);
    color: var(--text-color);
    font-weight: 600;
}

.article-content td {
    background-color: white;
    color: var(--text-color);
}

/* Responsive tables */
@media (max-width: 600px) {
    .article-content table {
        display: block;
        overflow-x: auto;
        -webkit-overflow-scrolling: touch;
    }
    
    .article-content th, .article-content td {
        white-space: nowrap;
    }
}

/* Article navigation styles */
.article-nav {
    margin-top: 40px;
    padding: 20px;
    border-top: 3px solid var(--link-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 20px;
    background: linear-gradient(135deg, var(--topic-item-bg) 0%, var(--card-bg) 100%);
    border-radius: var(--border-radius-md);
    box-shadow: 0 4px 12px var(--card-shadow);
    position: relative;
    /* Ensure navigation always appears at the bottom */
    order: 999;
    margin-bottom: 0;
    /* Prevent navigation from being overlooked */
    min-height: 60px;
}

.article-nav::before {
    content: '';
    position: absolute;
    top: -2px;
    left: 0;
    right: 0;
    height: 2px;
    background: linear-gradient(90deg, var(--link-color), var(--sidebar-hover), var(--link-color));
    border-radius: var(--border-radius-sm) var(--border-radius-sm) 0 0;
}

.article-nav a {
    display: inline-flex;
    align-items: center;
    font-weight: 500;
    color: var(--link-color);
    text-decoration: none;
    transition: all var(--transition-fast);
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--border-radius-sm);
    border: 1px solid transparent;
}

.article-nav a:hover {
    color: white;
    background-color: var(--link-color);
    border-color: var(--link-color);
    transform: translateY(-1px);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
}

.article-nav a i {
    margin: 0 8px;
    transition: transform var(--transition-fast);
}

.article-nav a:hover i {
    transform: scale(1.1);
}

/* Empty navigation divs for consistent layout */
.article-nav-prev:empty,
.article-nav-next:empty {
    flex: 1;
    min-height: 44px;
}

/* Categories and Tags */
.article-categories {
    margin: 10px 0;
}

.article-category-label {
    color: var(--secondary-text);
    font-size: 0.9rem;
    margin-right: 5px;
}

.article-category {
    display: inline-block;
    background-color: var(--sidebar-bg);
    color: var(--sidebar-text);
    font-size: 0.8rem;
    padding: 3px 8px;
    border-radius: 3px;
    margin-right: 5px;
    transition: all 0.2s ease;
    cursor: pointer;
}

.article-category:hover {
    background-color: var(--sidebar-active-bg);
}

.article-tags {
    margin-bottom: 20px;
}

.article-tag {
    display: inline-block;
    background-color: var(--topic-item-bg);
    color: var(--secondary-text);
    font-size: 0.8rem;
    padding: 2px 8px;
    border-radius: 12px;
    margin-right: 5px;
    border: 1px solid var(--border-color);
    transition: all 0.2s ease;
    cursor: pointer;
}

.article-tag:hover {
    background-color: var(--topic-item-hover);
    color: var(--text-color);
}

/* Pagination styles */
.pagination {
    display: flex;
    justify-content: center;
    margin-top: 30px;
    padding: 15px;
    border-top: 1px solid var(--border-color);
    flex-wrap: wrap;
    background-color: var(--topic-item-bg);
    border-radius: 8px;
    box-shadow: 0 2px 6px var(--card-shadow);
}

.pagination-item {
    margin: 5px;
    cursor: pointer;
}

.pagination-link {
    display: inline-flex;
    justify-content: center;
    align-items: center;
    min-width: 40px;
    height: 40px;
    padding: 0 10px;
    border-radius: 6px;
    background-color: var(--card-bg);
    color: var(--text-color);
    text-decoration: none;
    transition: all 0.3s ease;
    font-weight: 500;
    border: 1px solid var(--border-color);
}

.pagination-link:hover {
    background-color: var(--link-color);
    color: white;
    transform: translateY(-2px);
    box-shadow: 0 2px 4px var(--card-shadow);
}

.pagination-link.active {
    background-color: var(--link-color);
    color: white;
    border-color: var(--link-color);
}

.pagination-disabled {
    opacity: 0.5;
    cursor: not-allowed;
    pointer-events: none;
}

.pagination-item.pagination-ellipsis {
    display: flex;
    align-items: center;
    justify-content: center;
    min-width: 40px;
    height: 40px;
    font-weight: bold;
}

.pagination-prev .pagination-link,
.pagination-next .pagination-link {
    padding: 0 15px;
}

.article-nav-prev {
    text-align: left;
    flex: 1;
}

.article-nav-next {
    text-align: right;
    flex: 1;
}

/* Recent Articles Styles */
.recent-articles {
    margin-top: 40px;
    padding-top: 20px;
    border-top: 1px solid var(--border-color);
}

.recent-articles h3 {
    text-align: center;
    margin-bottom: 20px;
    font-size: 1.5rem;
    color: var(--text-color);
}

.recent-articles-list {
    list-style-type: none;
    padding: 0;
    max-width: 700px;
    margin: 0 auto;
}

.recent-articles-list li {
    margin-bottom: 15px;
    border-radius: 6px;
    transition: all 0.2s ease;
}

.recent-articles-list li:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 10px var(--card-shadow);
}

.recent-articles-list a {
    display: block;
    padding: 15px;
    text-decoration: none;
    background-color: var(--topic-item-bg);
    border-radius: 6px;
    transition: all 0.2s ease;
}

.recent-articles-list a:hover {
    background-color: var(--topic-item-hover);
}

.recent-article-title {
    color: var(--text-color);
    font-size: 1.1rem;
    font-weight: 500;
    margin-bottom: 5px;
}

.recent-article-meta {
    color: var(--secondary-text);
    font-size: 0.9rem;
}

.welcome-message {
    text-align: center;
    padding: 40px 20px;
}

.welcome-message h1 {
    font-size: 2.5rem;
    margin-bottom: 30px;
    color: var(--text-color);
}

.project-logo {
    margin: 20px auto 40px;
    text-align: center;
}

.project-logo img {
    max-width: 100%;
    height: auto;
    border-radius: 8px;
    box-shadow: 0 4px 12px var(--card-shadow);
    display: block;
    margin: 0 auto;
}

.project-description {
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}

.project-description h2 {
    font-size: 1.8rem;
    margin-bottom: 20px;
    color: var(--link-color);
}

.project-description h3 {
    font-size: 1.4rem;
    margin: 30px 0 20px;
    color: var(--text-color);
}

.project-description p {
    font-size: 1.1rem;
    line-height: 1.6;
    margin-bottom: 20px;
    color: var(--text-color);
}

.topic-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    grid-gap: 20px;
    margin: 30px auto;
    max-width: 600px;
}

.topic-item {
    background-color: var(--topic-item-bg);
    border-radius: 6px;
    padding: 15px 10px;
    display: flex;
    flex-direction: column;
    align-items: center;
    transition: all 0.3s ease;
}

.topic-item:hover {
    transform: translateY(-5px);
    background-color: var(--topic-item-hover);
    box-shadow: 0 5px 15px var(--card-shadow);
}

.topic-item i {
    font-size: 2rem;
    margin-bottom: 10px;
    color: var(--link-color);
}

.topic-item span {
    font-size: 1rem;
    font-weight: 500;
    color: var(--text-color);
}

/* Search Results Styles */
.search-results-container {
    max-width: 800px;
    margin: 0 auto;
}

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

.search-results-header h1 {
    font-size: 1.8rem;
    margin-bottom: 10px;
    color: var(--text-color);
}

.search-results-list {
    margin-top: 20px;
}

.search-result-item {
    padding: 15px;
    margin-bottom: 20px;
    border-radius: 6px;
    background-color: var(--topic-item-bg);
    transition: all 0.2s ease;
}

.search-result-item:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 10px var(--card-shadow);
}

.search-result-item h2 {
    margin-bottom: 10px;
    font-size: 1.4rem;
}

.search-result-item h2 a {
    color: var(--link-color);
    text-decoration: none;
}

.search-result-item h2 a:hover {
    text-decoration: underline;
}

.search-result-snippet {
    color: var(--secondary-text);
    font-size: 1rem;
    line-height: 1.5;
}

.highlight {
    background-color: var(--highlight-bg);
    border-radius: 2px;
    padding: 0 2px;
}

.search-no-results {
    text-align: center;
    padding: 30px 0;
    color: var(--secondary-text);
}

.clear-search-button {
    display: block;
    margin: 30px auto 0;
    padding: 10px 15px;
    background-color: var(--topic-item-bg);
    color: var(--text-color);
    border: none;
    border-radius: 4px;
    font-size: 0.9rem;
    cursor: pointer;
    transition: all 0.2s ease;
}

.clear-search-button:hover {
    background-color: var(--topic-item-hover);
}

/* Article List Styles */
.articles-list-container {
    max-width: 800px;
    margin: 0 auto;
}

.articles-list-title {
    font-size: 2rem;
    margin-bottom: 15px;
    color: var(--text-color);
    text-align: center;
}

.articles-list-info {
    text-align: center;
    margin-bottom: 30px;
    padding-bottom: 15px;
    border-bottom: 1px solid var(--border-color);
}

.articles-list-count {
    color: var(--secondary-text);
    font-size: 0.95rem;
}

.articles-list-count .count-total,
.articles-list-count .count-page,
.articles-list-count .count-total-pages {
    font-weight: 600;
    color: var(--link-color);
}

.article-list-item {
    border-bottom: 1px solid var(--border-color);
    padding: 25px 0;
}

.article-list-item:last-child {
    border-bottom: none;
}

.article-list-item h2 {
    margin-bottom: 10px;
    font-size: 1.5rem;
}

.article-list-item h2 a {
    color: var(--text-color);
    text-decoration: none;
    transition: color 0.2s;
}

.article-list-item h2 a:hover {
    color: var(--link-color);
}

.article-list-meta {
    color: var(--secondary-text);
    font-size: 0.9rem;
    margin-bottom: 10px;
    display: flex;
    flex-wrap: wrap;
}

.article-list-date {
    margin-right: 15px;
}

.article-list-categories {
    margin: 10px 0;
}

.article-list-tags {
    margin-bottom: 10px;
}

.article-list-snippet {
    color: var(--text-color);
    font-size: 1rem;
    margin-bottom: 15px;
    line-height: 1.6;
}

.read-more-link {
    display: inline-block;
    color: var(--link-color);
    text-decoration: none;
    font-weight: 500;
    font-size: 0.9rem;
    transition: color 0.2s;
}

.read-more-link:hover {
    color: var(--link-hover);
    text-decoration: underline;
}

.no-articles {
    text-align: center;
    padding: 50px 0;
    color: var(--secondary-text);
    font-style: italic;
}

.btn-primary {
    display: inline-block;
    padding: 10px 20px;
    background-color: var(--link-color);
    color: white;
    border-radius: 4px;
    text-decoration: none;
    font-weight: 500;
    transition: background-color 0.2s ease;
    margin-top: 20px;
}

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

/* Social Sharing Styles */
.social-share-container {
    margin-top: var(--spacing-xl);
    margin-bottom: var(--spacing-lg);
    padding: var(--spacing-lg);
    border-top: 1px solid var(--border-color);
    border-bottom: 1px solid var(--border-color);
    text-align: center;
    background-color: rgba(0, 0, 0, 0.02);
    border-radius: var(--border-radius-md);
    /* Ensure social sharing appears before navigation */
    order: 3;
}

.dark-mode .social-share-container {
    background-color: rgba(255, 255, 255, 0.03);
}

.social-share-title {
    margin-bottom: var(--spacing-md);
    font-size: var(--font-size-md);
    color: var(--text-color);
    font-weight: 500;
}

.social-share-buttons {
    display: flex;
    justify-content: center;
    gap: var(--spacing-md);
    flex-wrap: wrap;
}

.social-share-button {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border-radius: var(--border-radius-circle);
    color: white;
    text-decoration: none;
    transition: transform var(--transition-fast), box-shadow var(--transition-fast);
    cursor: pointer;
    border: none;
    font-size: var(--font-size-md);
}

.social-share-button:hover {
    transform: translateY(-3px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
}

.social-share-button:focus-visible {
    outline: 2px solid white;
    outline-offset: 2px;
}

.social-share-button.twitter {
    background-color: #1DA1F2;
}

.social-share-button.facebook {
    background-color: #4267B2;
}

.social-share-button.linkedin {
    background-color: #0077B5;
}

.social-share-button.email {
    background-color: #738A8D;
}

.social-share-button.copy-link {
    background-color: var(--sidebar-bg);
}

.social-share-button.copied {
    background-color: #4CAF50 !important;
    animation: copySuccess 1s ease-in-out;
}

.social-share-button.copy-error {
    background-color: #f44336 !important;
    animation: copyError 1s ease-in-out;
}

@keyframes pulse {
    0% { transform: scale(1); }
    50% { transform: scale(1.1); }
    100% { transform: scale(1); }
}

@keyframes copySuccess {
    0% { transform: scale(1); background-color: var(--sidebar-bg); }
    25% { transform: scale(1.15); }
    50% { transform: scale(1.1); background-color: #4CAF50; }
    100% { transform: scale(1); background-color: #4CAF50; }
}

@keyframes copyError {
    0% { transform: scale(1); }
    25% { transform: translateX(-5px); }
    50% { transform: translateX(5px); }
    75% { transform: translateX(-3px); }
    100% { transform: translateX(0); }
}

/* 
 * Font size controls - REMOVED
 * These styles have been commented out as the font size controls have been removed from the UI
 *
.font-size-controls {
    position: fixed;
    top: 60px;
    right: 20px;
    display: flex;
    flex-direction: column;
    background: var(--card-bg);
    border-radius: var(--border-radius-md);
    box-shadow: 0 2px 8px var(--card-shadow);
    z-index: 100;
    padding: var(--spacing-xs);
}

.font-size-controls button {
    background: transparent;
    border: none;
    color: var(--text-color);
    cursor: pointer;
    width: 40px;
    height: 40px;
    border-radius: var(--border-radius-circle);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background-color var(--transition-fast);
}

.font-size-controls button:hover {
    background-color: var(--border-color);
}

.font-size-controls button:focus {
    outline: 2px solid var(--link-color);
    outline-offset: 2px;
}

/* Font size classes applied to body */
body.font-size-small {
    font-size: 14px;
}

body.font-size-normal {
    font-size: 16px;
}

body.font-size-large {
    font-size: 18px;
}

body.font-size-extra-large {
    font-size: 20px;
}
*/

/* Responsive design - Mobile First */
.sidebar {
    width: 100%;
    height: auto;
    position: relative;
    padding: var(--spacing-md) 0;
}

.content {
    margin-left: 0;
    padding: var(--spacing-md);
    width: 100%;
}

.topic-grid {
    grid-template-columns: 1fr;
    gap: var(--spacing-md);
}

.welcome-message {
    padding: var(--spacing-md);
}

.article-header {
    padding: 0 var(--spacing-md) var(--spacing-md) var(--spacing-md);
}

.article-content {
    padding: 0 var(--spacing-md) var(--spacing-md) var(--spacing-md);
}

.article-nav {
    flex-direction: column;
    gap: var(--spacing-md);
    padding: var(--spacing-md);
    margin-top: var(--spacing-lg);
    /* Ensure navigation is always at the bottom on mobile */
    margin-bottom: 0;
}

.article-nav-next, .article-nav-prev {
    text-align: center;
    width: 100%;
}

.article-nav-prev, .article-nav-next {
    min-height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.article-nav a {
    padding: var(--spacing-sm);
    border-radius: var(--border-radius-sm);
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    width: 100%;
    text-align: center;
    transition: all var(--transition-fast);
}

.article-nav a:hover {
    background-color: var(--link-color);
    color: white;
    transform: translateY(-1px);
}

/* Prevent text selection on UI elements for better mobile UX */
.mobile-menu-toggle,
.search-toggle,
.theme-toggle,
.pagination-link,
.article-nav a,
.hamburger-line {
    -webkit-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
    -webkit-touch-callout: none;
}

/* Improve form inputs on mobile */
input[type="text"],
input[type="search"] {
    -webkit-appearance: none;
    -moz-appearance: none;
    appearance: none;
    border-radius: var(--border-radius-sm);
}

/* Increase tap target sizes for mobile */
.article-tag, .article-category, .social-share-button, #search-button {
    min-height: 44px;
    min-width: 44px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    margin-bottom: var(--spacing-sm);
}

/* Tablet styles */
@media (min-width: 576px) and (max-width: 1023px) {
    .theme-toggle-container {
        bottom: var(--spacing-md);
        right: var(--spacing-md); /* Moved to bottom right */
    }
    
    .topic-grid {
        grid-template-columns: repeat(2, 1fr);
    }      .article-nav {
        flex-direction: row;
        padding: var(--spacing-lg);
        gap: var(--spacing-lg);
    }
    
    .article-nav-prev {
        text-align: left;
        flex: 1;
    }
    
    .article-nav-next {
        text-align: right;
        flex: 1;
    }
    
    .article-nav a {
        width: auto;
        max-width: 200px;
    }
}

/* Desktop styles */
@media (min-width: 768px) {
    .container {
        flex-direction: row;
    }
    
    .sidebar {
        width: 250px;
        height: 100%;
        position: fixed;
        padding: var(--spacing-lg) 0;
    }
    
    .content {
        margin-left: 250px;
        padding: var(--spacing-lg);
    }
      .welcome-message {
        padding: var(--spacing-lg);
    }
    
    .article-header {
        padding: 0 var(--spacing-lg) var(--spacing-lg) var(--spacing-lg);
    }
    
    .article-content {
        padding: 0 var(--spacing-lg) var(--spacing-lg) var(--spacing-lg);
    }
    
    .topic-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

/* Large Desktop styles */
@media (min-width: 1200px) {
    .content {
        max-width: calc(100% - 250px);
        margin-left: 250px;
    }
    
    .article-content {
        max-width: 800px;
        margin: 0 auto;
    }
    
    .topic-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

/* Print styles */
@media print {
    /* Hide non-essential elements when printing */
    .sidebar, 
    .theme-toggle-container, 
    .skip-link, 
    .social-share-container, 
    .article-nav {
        display: none !important;
    }
    
    /* Reset layout for printing */
    .container {
        display: block;
    }
    
    .content {
        margin: 0;
        padding: 0;
        width: 100%;
        max-width: 100%;
    }
    
    /* Typography adjustments for print */
    body {
        font-size: 12pt;
        line-height: 1.5;
        color: #000;
        background: #fff;
    }
    
    h1, h2, h3, h4, h5, h6 {
        page-break-after: avoid;
        page-break-inside: avoid;
    }
    
    h1 {
        font-size: 18pt;
        margin-bottom: 0.5cm;
    }
    
    h2 {
        font-size: 16pt;
        margin-top: 1cm;
    }
    
    p, blockquote, ul, ol, dl, table {
        page-break-inside: avoid;
        margin-bottom: 0.5cm;
    }
    
    /* URLs after links */
    a[href^="http"]:after {
        content: " (" attr(href) ")";
        font-size: 10pt;
        font-style: italic;
    }
    
    /* Don't show URL for internal links */
    a[href^="#"]:after {
        content: "";
    }
    
    /* Improve code printing */
    pre, code {
        border: 1px solid #ddd;
        page-break-inside: avoid;
        font-size: 10pt;
        background: none;
        color: #000;
    }
    
    /* Add page footer with source */
    @page {
        margin: 2cm 1.5cm;
    }
    
    @page:first {
        margin-top: 2cm;
    }
    
    /* Add a header with the article title */
    .article-header::after {
        content: "Printed from GSATechDose";
        display: block;
        text-align: center;
        font-size: 9pt;
        color: #666;
        margin-top: 1cm;
    }
}

/* Theme toggle styles for mobile screens */
@media (max-width: 575px) {
    .theme-toggle-container {
        bottom: var(--spacing-md);
        right: var(--spacing-md); /* Moved to bottom right */
        padding: var(--spacing-xs);
    }
    
    /* Make the toggle button slightly larger on small screens for better touch targets */
    .theme-toggle {
        font-size: 1.2rem;
        padding: 8px;
    }
}

/* Categories page styles */
.categories-page {
    margin: 0 auto;
    max-width: 900px;
    padding: var(--spacing-lg);
}

.categories-page h1 {
    margin-bottom: var(--spacing-md);
    color: var(--text-color);
    font-size: var(--font-size-xxl);
    text-align: center;
}

.categories-intro {
    text-align: center;
    margin-bottom: var(--spacing-xl);
    color: var(--text-color-secondary);
}

.categories-container {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xl);
}

.category-section {
    background-color: var(--card-bg);
    border-radius: var(--border-radius-md);
    box-shadow: 0 2px 8px var(--card-shadow);
    padding: var(--spacing-lg);
    transition: transform var(--transition-fast);
}

.category-section:hover {
    transform: translateY(-3px);
}

.category-title {
    color: var(--text-color);
    font-size: var(--font-size-xl);
    margin-bottom: var(--spacing-md);
    padding-bottom: var(--spacing-sm);
    border-bottom: 2px solid var(--link-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.category-count {
    background-color: var(--link-color);
    color: white;
    font-size: var(--font-size-sm);
    padding: 2px 8px;
    border-radius: var(--border-radius-sm);
    font-weight: normal;
}

.category-articles {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.category-article-item {
    padding: var(--spacing-md);
    background-color: rgba(0, 0, 0, 0.03);
    border-radius: var(--border-radius-sm);
    transition: background-color var(--transition-fast);
}

.dark-mode .category-article-item {
    background-color: rgba(255, 255, 255, 0.05);
}

.category-article-item:hover {
    background-color: rgba(0, 0, 0, 0.06);
}

.dark-mode .category-article-item:hover {
    background-color: rgba(255, 255, 255, 0.08);
}

.category-article-item.read .article-title a {
    color: var(--text-color-secondary);
}

.category-article-item .article-title {
    margin-bottom: var(--spacing-xs);
    font-size: var(--font-size-lg);
}

.category-article-item .article-meta {
    font-size: var(--font-size-sm);
    color: var(--text-color-secondary);
    margin-bottom: var(--spacing-xs);
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-md);
}

.categories-filter {
    margin-bottom: var(--spacing-xl);
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: var(--spacing-md);
    padding-bottom: var(--spacing-md);
    border-bottom: 1px solid var(--border-color);
}

.categories-search {
    flex: 1;
    max-width: 400px;
    position: relative;
}

.categories-search input {
    width: 100%;
    padding: var(--spacing-sm) var(--spacing-md);
    padding-left: 36px;
    border-radius: var(--border-radius-sm);
    border: 1px solid var(--border-color);
    background-color: var(--card-bg);
    color: var(--text-color);
}

.categories-search i {
    position: absolute;
    left: var(--spacing-sm);
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-color-secondary);
}

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

.categories-sort label {
    color: var(--text-color-secondary);
    font-size: var(--font-size-sm);
}

.categories-sort select {
    padding: 6px var(--spacing-md);
    border-radius: var(--border-radius-sm);
    border: 1px solid var(--border-color);
    background-color: var(--card-bg);
    color: var(--text-color);
}

.categories-navigation {
    margin-top: var(--spacing-xl);
    text-align: center;
}

.categories-navigation a {
    display: inline-block;
    padding: var(--spacing-sm) var(--spacing-md);
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    color: var(--link-color);
    border-radius: var(--border-radius-sm);
    text-decoration: none;
    margin-right: var(--spacing-sm);
    transition: all var(--transition-fast);
}

.categories-navigation a:hover {
    background-color: var(--link-color);
    color: white;
}

.category-icon {
    margin-right: var(--spacing-sm);
    color: var(--link-color);
}

/* Enhanced Categories Page Styles */
.categories-page .page-header {
    text-align: center;
    margin-bottom: var(--spacing-xl);
    padding-bottom: var(--spacing-lg);
    border-bottom: 2px solid var(--border-color);
}

.categories-page .page-header h1 {
    color: var(--text-color);
    font-size: var(--font-size-xxl);
    margin-bottom: var(--spacing-md);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
}

.categories-page .page-header h1 i {
    color: var(--link-color);
    font-size: 1.8rem;
}

.categories-page .page-intro {
    color: var(--text-color-secondary);
    font-size: var(--font-size-lg);
    max-width: 600px;
    margin: 0 auto;
    line-height: 1.6;
}

.categories-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: var(--spacing-lg);
    margin-top: var(--spacing-xl);
}

.category-card {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-lg);
    padding: var(--spacing-lg);
    transition: all var(--transition-medium);
    box-shadow: 0 2px 8px var(--card-shadow);
}

.category-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 20px var(--card-shadow);
    border-color: var(--link-color);
}

.category-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-md);
    padding-bottom: var(--spacing-sm);
    border-bottom: 1px solid var(--border-color);
}

.category-title {
    margin: 0;
    font-size: var(--font-size-xl);
}

.category-title a {
    color: var(--text-color);
    text-decoration: none;
    transition: color var(--transition-fast);
}

.category-title a:hover {
    color: var(--link-color);
}

.category-count {
    background: var(--link-color);
    color: white;
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--border-radius-md);
    font-size: var(--font-size-sm);
    font-weight: 600;
}

.category-preview h4 {
    color: var(--text-color-secondary);
    font-size: var(--font-size-sm);
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.category-articles-preview {
    list-style: none;
    margin: 0;
    padding: 0;
}

.category-articles-preview li {
    margin-bottom: var(--spacing-sm);
    padding: var(--spacing-sm);
    border-radius: var(--border-radius-sm);
    transition: background-color var(--transition-fast);
}

.category-articles-preview li:hover {
    background-color: var(--topic-item-hover);
}

.category-articles-preview .article-preview-link {
    color: var(--text-color);
    text-decoration: none;
    font-weight: 500;
    display: block;
    margin-bottom: var(--spacing-xs);
    transition: color var(--transition-fast);
}

.category-articles-preview .article-preview-link:hover {
    color: var(--link-color);
}

.category-articles-preview .article-date {
    color: var(--text-color-muted);
    font-size: var(--font-size-xs);
}

.category-articles-preview .show-more {
    margin-top: var(--spacing-sm);
    padding-top: var(--spacing-sm);
    border-top: 1px solid var(--border-color);
}

.category-articles-preview .show-more a {
    color: var(--link-color);
    text-decoration: none;
    font-weight: 600;
    font-size: var(--font-size-sm);
    transition: color var(--transition-fast);
}

.category-articles-preview .show-more a:hover {
    color: var(--link-hover);
}

/* Responsive design for categories page */
@media (max-width: 768px) {
    .categories-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-md);
    }
    
    .category-card {
        padding: var(--spacing-md);
    }
    
    .categories-page .page-header h1 {
        font-size: var(--font-size-xl);
        flex-direction: column;
        gap: var(--spacing-xs);
    }
    
    .categories-page .page-intro {
        font-size: var(--font-size-md);
    }
}

@media (max-width: 480px) {
    .category-header {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--spacing-xs);
    }
    
    .category-title {
        font-size: var(--font-size-lg);
    }
}

/* Accessibility improvements */
.sr-only {
    position: absolute !important;
    width: 1px !important;
    height: 1px !important;
    padding: 0 !important;
    margin: -1px !important;
    overflow: hidden !important;
    clip: rect(0, 0, 0, 0) !important;
    white-space: nowrap !important;
    border: 0 !important;
}

/* Enhanced article layout styles for new navigation positioning */
.article-content {
    margin-bottom: var(--spacing-lg);
}

/* Ensure proper spacing before navigation */
.article-nav {
    border-top-width: 3px;
    border-top-style: solid;
    border-top-color: var(--link-color);
}

/* Print styles - ensure navigation appears correctly when printed */
@media print {
    .article-nav {
        margin-top: 2cm;
        padding: 0.5cm;
        border-top: 2px solid #333;
        background: none !important;
        box-shadow: none !important;
        page-break-inside: avoid;
    }
    
    .article-nav a {
        color: #333 !important;
        background: none !important;
        border: 1px solid #333 !important;
    }
}

/* Focus styles for better accessibility */
.article-nav a:focus {
    outline: 3px solid var(--link-color);
    outline-offset: 2px;
    box-shadow: 0 0 0 2px white, 0 0 0 5px var(--link-color);
}

/* Loading state styles */
.article-nav.loading {
    opacity: 0.6;
    pointer-events: none;
}

.article-nav.loading::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 20px;
    height: 20px;
    border: 2px solid var(--border-color);
    border-top: 2px solid var(--link-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

/* Mobile loading states for better perceived performance */
.article-container.loading {
    opacity: 0.7;
    pointer-events: none;
    transition: opacity var(--transition-fast);
}

.article-container.loading::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 24px;
    height: 24px;
    border: 2px solid var(--border-color);
    border-top: 2px solid var(--link-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    z-index: 1000;
}

/* Optimize animations for mobile devices */
@media (max-width: 767px) {
    .article-container.loading::after {
        width: 20px;
        height: 20px;
    }
}

/* Search toggle styles */
.search-toggle-container {
    position: fixed;
    top: var(--spacing-md);
    right: var(--spacing-md);
    z-index: 1011;
    padding: var(--spacing-xs);
    background-color: var(--card-bg);
    border-radius: var(--border-radius-circle);
    box-shadow: 0 2px 8px var(--card-shadow);
    transition: transform var(--transition-fast), box-shadow var(--transition-fast), opacity var(--transition-medium), visibility var(--transition-medium);
}

/* Hide search toggle when search is active */
.search-toggle-container.hidden {
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
}

.search-toggle-container:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px var(--card-shadow);
}

.search-toggle {
    background: none;
    border: none;
    color: var(--text-color);
    font-size: 1.2rem;
    cursor: pointer;
    transition: color var(--transition-fast), transform var(--transition-fast);
    padding: var(--spacing-sm);
    width: 40px;
    height: 40px;
    border-radius: var(--border-radius-circle);
    display: flex;
    align-items: center;
    justify-content: center;
}

.search-toggle:hover {
    color: var(--link-color);
    transform: scale(1.1);
}

.search-toggle:focus-visible {
    outline: 2px solid var(--link-color);
    outline-offset: 2px;
}

/* Animated search overlay */
.search-overlay {
    position: fixed;
    top: 0;
    right: 0;
    width: 100%;
    height: 100vh;
    background-color: rgba(0, 0, 0, 0.5);
    z-index: 1010;
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--transition-medium), visibility var(--transition-medium);
}

.search-overlay.active {
    opacity: 1;
    visibility: visible;
}

.search-box {
    position: absolute;
    top: var(--spacing-md);
    right: var(--spacing-md);
    width: 400px;
    max-width: calc(100vw - 2 * var(--spacing-md));
    background-color: var(--card-bg);
    border-radius: var(--border-radius-md);
    box-shadow: 0 4px 20px var(--card-shadow);
    padding: var(--spacing-md);
    transform: translateX(100%);
    transition: transform var(--transition-medium);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.search-overlay.active .search-box {
    transform: translateX(0);
}

.search-box #search-input {
    flex: 1;
    padding: var(--spacing-sm) var(--spacing-md);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-sm);
    background-color: var(--search-bg);
    color: var(--search-text);
    font-size: 1rem;
}

.search-box #search-input::placeholder {
    color: var(--search-placeholder);
}

.search-box #search-input:focus {
    outline: 2px solid var(--search-focus-outline);
    border-color: var(--search-focus-outline);
}

.search-box #search-button {
    padding: var(--spacing-sm);
    background-color: var(--link-color);
    color: white;
    border: none;
    border-radius: var(--border-radius-sm);
    cursor: pointer;
    transition: background-color var(--transition-fast);
    display: flex;
    align-items: center;
    justify-content: center;
    min-width: 40px;
    height: 40px;
}

.search-box #search-button:hover {
    background-color: var(--link-hover);
}

.search-close {
    padding: var(--spacing-sm);
    background: none;
    border: none;
    color: var(--text-color-secondary);
    cursor: pointer;
    transition: color var(--transition-fast);
    display: flex;
    align-items: center;
    justify-content: center;
    min-width: 40px;
    height: 40px;
}

.search-close:hover {
    color: var(--text-color);
}

/* Search results positioning for overlay */
.search-overlay .search-results {
    position: absolute;
    top: calc(100% + var(--spacing-sm));
    left: 0;
    right: 0;
    background-color: var(--card-bg);
    border-radius: var(--border-radius-sm);
    box-shadow: 0 4px 12px var(--card-shadow);
    max-height: 300px;
    overflow-y: auto;
    z-index: 10;
}

/* Mobile Navigation Enhancements */
.mobile-menu-toggle-container {
    position: fixed;
    top: var(--spacing-md);
    left: var(--spacing-md);
    z-index: 1012;
    background-color: var(--card-bg);
    border-radius: var(--border-radius-circle);
    box-shadow: 0 2px 8px var(--card-shadow);
    padding: var(--spacing-xs);
    display: none; /* Hidden by default, shown on mobile */
    transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

.mobile-menu-toggle-container:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px var(--card-shadow);
}

.mobile-menu-toggle {
    background: none;
    border: none;
    color: var(--text-color);
    font-size: 1.2rem;
    cursor: pointer;
    padding: var(--spacing-sm);
    width: 44px;
    height: 44px;
    border-radius: var(--border-radius-circle);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 3px;
    transition: color var(--transition-fast);
}

.hamburger-line {
    width: 20px;
    height: 2px;
    background-color: var(--text-color);
    transition: all var(--transition-fast);
    border-radius: 1px;
}

.mobile-menu-toggle:hover {
    color: var(--link-color);
}

.mobile-menu-toggle:hover .hamburger-line {
    background-color: var(--link-color);
}

.mobile-menu-toggle.active .hamburger-line:nth-child(1) {
    transform: translateY(5px) rotate(45deg);
}

.mobile-menu-toggle.active .hamburger-line:nth-child(2) {
    opacity: 0;
}

.mobile-menu-toggle.active .hamburger-line:nth-child(3) {
    transform: translateY(-5px) rotate(-45deg);
}

.mobile-menu-toggle:focus-visible {
    outline: 2px solid var(--link-color);
    outline-offset: 2px;
}

/* Mobile Overlay */
.mobile-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    background-color: rgba(0, 0, 0, 0.5);
    z-index: 999;
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--transition-medium), visibility var(--transition-medium);
}

.mobile-overlay.active {
    opacity: 1;
    visibility: visible;
}

/* Enhanced Mobile Responsive Sidebar */
.sidebar {
    will-change: transform;
}

.sidebar.mobile-open {
    transform: translateX(0);
}

/* Search toggle positioning improvements for mobile */
@media (max-width: 575px) {
    .search-toggle-container {
        top: var(--spacing-md);
        right: var(--spacing-md);
        bottom: auto;
    }
    
    .theme-toggle-container {
        bottom: var(--spacing-md);
        right: var(--spacing-md);
    }
    
    .mobile-menu-toggle-container {
        display: flex;
    }
    
    /* Mobile sidebar improvements */
    .sidebar {
        transform: translateX(-100%);
        z-index: 1000;
        box-shadow: 2px 0 8px rgba(0, 0, 0, 0.15);
    }
    
    .sidebar.mobile-open {
        transform: translateX(0);
    }
    
    /* Ensure content doesn't get cut off on mobile */
    .content {
        padding: var(--spacing-sm);
        min-height: calc(100vh - 2 * var(--spacing-sm));
    }
    
    .article-container {
        padding: var(--spacing-md);
    }
    
    /* Better mobile search overlay */
    .search-box {
        top: 60px;
        right: var(--spacing-sm);
        left: var(--spacing-sm);
        width: auto;
        max-width: none;
    }
    
    .search-box #search-input {
        font-size: 16px; /* Prevent zoom on iOS */
    }
    
    /* Improve topic grid on mobile */
    .topic-grid {
        grid-template-columns: 1fr 1fr;
        gap: var(--spacing-sm);
    }
    
    .topic-item {
        padding: var(--spacing-sm);
        text-align: center;
    }
    
    .topic-item i {
        font-size: 1.5rem;
    }
    
    .topic-item span {
        font-size: 0.9rem;
    }
    
    /* Mobile article navigation improvements */
    .article-nav {
        padding: var(--spacing-sm);
        gap: var(--spacing-sm);
    }
    
    .article-nav a {
        padding: var(--spacing-md);
        font-size: var(--font-size-sm);
        min-height: 48px;
    }
    
    /* Mobile categories improvements */
    .categories-page {
        padding: var(--spacing-md);
    }
    
    .category-card {
        padding: var(--spacing-sm);
    }
    
    .categories-page .page-header h1 {
        font-size: var(--font-size-xl);
    }
    
    /* Mobile social sharing */
    .social-share-container {
        padding: var(--spacing-md);
    }
    
    .social-share-buttons {
        gap: var(--spacing-sm);
    }
    
    .social-share-button {
        width: 44px;
        height: 44px;
    }
    
    /* Mobile pagination */
    .pagination {
        padding: var(--spacing-sm);
        gap: var(--spacing-xs);
    }
    
    .pagination-link {
        min-width: 36px;
        height: 36px;
        padding: 0 8px;
        font-size: var(--font-size-sm);
    }
}

/* Tablet specific improvements */
@media (min-width: 576px) and (max-width: 767px) {
    .mobile-menu-toggle-container {
        display: flex;
    }
    
    .sidebar {
        transform: translateX(-100%);
        z-index: 1000;
    }
    
    .sidebar.mobile-open {
        transform: translateX(0);
    }
    
    .topic-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .search-box {
        width: 350px;
    }
}

/* Small phones */
@media (max-width: 375px) {
    .topic-grid {
        grid-template-columns: 1fr;
    }
    
    .categories-page .page-header h1 {
        font-size: var(--font-size-lg);
    }
    
    .article-title {
        font-size: 1.8rem;
    }
    
    .welcome-message h1 {
        font-size: 2rem;
    }
    
    .search-box {
        padding: var(--spacing-sm);
    }
}

/* Landscape phone orientation */
@media (max-width: 767px) and (orientation: landscape) {
    .welcome-message {
        padding: var(--spacing-sm);
    }
    
    .project-logo {
        margin: var(--spacing-md) auto;
    }
    
    .project-logo img {
        max-width: 200px;
    }
}

/* High DPI displays */
@media (-webkit-min-device-pixel-ratio: 2), (min-resolution: 192dpi) {
    .sidebar-icon,
    .project-logo img {
        image-rendering: -webkit-optimize-contrast;
        image-rendering: crisp-edges;
    }
}

/* Touch device improvements */
@media (hover: none) and (pointer: coarse) {
    /* Remove hover effects on touch devices */
    .topic-item:hover,
    .category-card:hover,
    .recent-articles-list li:hover {
        transform: none;
    }
    
    /* Increase touch targets for better accessibility */
    .article-tag,
    .article-category,
    .pagination-link {
        min-height: 48px;
        min-width: 48px;
    }
    
    /* Improve button feedback on touch */
    .theme-toggle:active,
    .search-toggle:active,
    .mobile-menu-toggle:active {
        transform: scale(0.95);
    }
    
    /* Improve scrolling performance on touch devices */
    .sidebar-menu {
        -webkit-overflow-scrolling: touch;
        overscroll-behavior: contain;
    }
    
    .search-box,
    .article-content {
        -webkit-overflow-scrolling: touch;
    }
}

/* Prevent overscroll behavior on mobile */
body {
    overscroll-behavior-y: none;
}

/* Safe area support for devices with notches (iPhone X+) */
@supports (padding: max(0px)) {
    .mobile-menu-toggle-container {
        top: max(var(--spacing-md), env(safe-area-inset-top));
        left: max(var(--spacing-md), env(safe-area-inset-left));
    }
    
    .search-toggle-container {
        top: max(var(--spacing-md), env(safe-area-inset-top));
        right: max(var(--spacing-md), env(safe-area-inset-right));
    }
    
    .theme-toggle-container {
        bottom: max(var(--spacing-md), env(safe-area-inset-bottom));
        right: max(var(--spacing-md), env(safe-area-inset-right));
    }
    
    .content {
        padding-left: max(var(--spacing-md), env(safe-area-inset-left));
        padding-right: max(var(--spacing-md), env(safe-area-inset-right));
    }
}

/* Enhanced accessibility for sidebar navigation */
.brand-link:focus-visible,
.nav-list a:focus-visible {
    outline: 2px solid var(--sidebar-hover);
    outline-offset: 2px;
    background-color: rgba(255, 255, 255, 0.1);
}

/* Active state for navigation items */
.nav-list li.active {
    background-color: var(--sidebar-hover);
    border-left: 3px solid var(--sidebar-text);
}

.nav-list li.active a {
    color: white;
    font-weight: 600;
}

/* Responsive improvements for the refactored sidebar */
@media (max-width: 767px) {
    .sidebar-header {
        padding: 0 var(--spacing-md);
        position: relative;
    }
    
    .brand-link {
        font-size: var(--font-size-md);
        gap: var(--spacing-xs);
    }
    
    .sidebar-icon {
        width: 24px;
        height: 24px;
    }
    
    .sidebar-navigation {
        padding: var(--spacing-sm) 0;
    }
    
    .nav-list a {
        padding: var(--spacing-sm) var(--spacing-md);
    }
}

/* Improve visual hierarchy on larger screens */
@media (min-width: 768px) {
    .sidebar-header {
        padding: 0 var(--spacing-lg);
    }
    
    .brand-link {
        font-size: var(--font-size-xl);
    }
    
    .sidebar-icon {
        width: 32px;
        height: 32px;
    }
}