/* ==========================================
   DOCUMENTATION SYSTEM - EXTENSIVE CSS
   Modern, Animated, Multi-Theme Design
   ========================================== */

/* ==========================================
   CSS VARIABLES - THEME SYSTEM
   ========================================== */

:root {
    --transition-speed: 0.3s;
    --border-radius: 8px;
    --sidebar-width: 280px;
    --header-height: 70px;
    --toc-width: 250px;
}

/* Dark Theme (Default) */
[data-theme="dark"] {
    --bg-primary: #0f172a;
    --bg-secondary: #1e293b;
    --bg-tertiary: #334155;
    --text-primary: #f1f5f9;
    --text-secondary: #cbd5e1;
    --text-muted: #94a3b8;
    --accent-primary: #3b82f6;
    --accent-secondary: #60a5fa;
    --border-color: #334155;
    --shadow-color: rgba(0, 0, 0, 0.3);
    --gradient-start: #3b82f6;
    --gradient-end: #8b5cf6;
    --code-bg: #1e293b;
    --search-highlight: #fbbf24;
}

/* Light Theme */
[data-theme="light"] {
    --bg-primary: #ffffff;
    --bg-secondary: #f8fafc;
    --bg-tertiary: #e2e8f0;
    --text-primary: #0f172a;
    --text-secondary: #475569;
    --text-muted: #64748b;
    --accent-primary: #3b82f6;
    --accent-secondary: #2563eb;
    --border-color: #e2e8f0;
    --shadow-color: rgba(0, 0, 0, 0.1);
    --gradient-start: #3b82f6;
    --gradient-end: #8b5cf6;
    --code-bg: #f1f5f9;
    --search-highlight: #fbbf24;
}

/* Ocean Theme */
[data-theme="ocean"] {
    --bg-primary: #0a192f;
    --bg-secondary: #112240;
    --bg-tertiary: #1d3557;
    --text-primary: #ccd6f6;
    --text-secondary: #a8b2d1;
    --text-muted: #8892b0;
    --accent-primary: #64ffda;
    --accent-secondary: #57cbff;
    --border-color: #1d3557;
    --shadow-color: rgba(0, 0, 0, 0.4);
    --gradient-start: #64ffda;
    --gradient-end: #57cbff;
    --code-bg: #112240;
    --search-highlight: #ffd700;
}

/* Forest Theme */
[data-theme="forest"] {
    --bg-primary: #1a2e1a;
    --bg-secondary: #2d4a2d;
    --bg-tertiary: #3d5a3d;
    --text-primary: #e8f5e8;
    --text-secondary: #c5e1c5;
    --text-muted: #a0c9a0;
    --accent-primary: #4ade80;
    --accent-secondary: #86efac;
    --border-color: #3d5a3d;
    --shadow-color: rgba(0, 0, 0, 0.4);
    --gradient-start: #4ade80;
    --gradient-end: #10b981;
    --code-bg: #2d4a2d;
    --search-highlight: #fbbf24;
}

/* Sunset Theme */
[data-theme="sunset"] {
    --bg-primary: #2d1b2e;
    --bg-secondary: #3e2c41;
    --bg-tertiary: #4f3d54;
    --text-primary: #ffeaa7;
    --text-secondary: #fdcb6e;
    --text-muted: #f39c12;
    --accent-primary: #ff6b6b;
    --accent-secondary: #ee5a6f;
    --border-color: #4f3d54;
    --shadow-color: rgba(0, 0, 0, 0.5);
    --gradient-start: #ff6b6b;
    --gradient-end: #feca57;
    --code-bg: #3e2c41;
    --search-highlight: #fbbf24;
}

/* Neon Theme */
[data-theme="neon"] {
    --bg-primary: #0d0221;
    --bg-secondary: #1a0b2e;
    --bg-tertiary: #2d1b4e;
    --text-primary: #f0f3ff;
    --text-secondary: #d4adfc;
    --text-muted: #a78bfa;
    --accent-primary: #ff00ff;
    --accent-secondary: #00ffff;
    --border-color: #2d1b4e;
    --shadow-color: rgba(255, 0, 255, 0.3);
    --gradient-start: #ff00ff;
    --gradient-end: #00ffff;
    --code-bg: #1a0b2e;
    --search-highlight: #ffff00;
}

/* Midnight Theme */
[data-theme="midnight"] {
    --bg-primary: #0c1021;
    --bg-secondary: #161b2e;
    --bg-tertiary: #1f2937;
    --text-primary: #e0e7ff;
    --text-secondary: #c7d2fe;
    --text-muted: #a5b4fc;
    --accent-primary: #818cf8;
    --accent-secondary: #a5b4fc;
    --border-color: #1f2937;
    --shadow-color: rgba(0, 0, 0, 0.6);
    --gradient-start: #818cf8;
    --gradient-end: #4f46e5;
    --code-bg: #161b2e;
    --search-highlight: #fbbf24;
}

/* Spring Theme */
[data-theme="spring"] {
    --bg-primary: #fef3e2;
    --bg-secondary: #fae8c8;
    --bg-tertiary: #f5d99f;
    --text-primary: #2d3436;
    --text-secondary: #636e72;
    --text-muted: #b2bec3;
    --accent-primary: #fd79a8;
    --accent-secondary: #fdcb6e;
    --border-color: #f5d99f;
    --shadow-color: rgba(0, 0, 0, 0.1);
    --gradient-start: #fd79a8;
    --gradient-end: #fdcb6e;
    --code-bg: #fae8c8;
    --search-highlight: #ff6b6b;
}

/* ==========================================
   GLOBAL STYLES
   ========================================== */

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    transition: background-color var(--transition-speed) ease,
                color var(--transition-speed) ease;
    overflow-x: hidden;
}

/* ==========================================
   ANIMATIONS & TRANSITIONS
   ========================================== */

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes slideInLeft {
    from {
        transform: translateX(-100%);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

@keyframes slideInRight {
    from {
        transform: translateX(100%);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

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

@keyframes gradient {
    0% {
        background-position: 0% 50%;
    }
    50% {
        background-position: 100% 50%;
    }
    100% {
        background-position: 0% 50%;
    }
}

@keyframes float {
    0%, 100% {
        transform: translateY(0px);
    }
    50% {
        transform: translateY(-10px);
    }
}

@keyframes shimmer {
    0% {
        background-position: -1000px 0;
    }
    100% {
        background-position: 1000px 0;
    }
}

/* ==========================================
   UTILITIES
   ========================================== */

.container-custom {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 2rem;
}

.gradient-text {
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
    background-size: 200% 200%;
    animation: gradient 3s ease infinite;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* ==========================================
   HEADER
   ========================================== */

header {
    background-color: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    backdrop-filter: blur(10px);
    height: var(--header-height);
    display: flex;
    align-items: center;
    animation: fadeIn 0.5s ease;
}

.header-blur {
    background-color: rgba(var(--bg-secondary-rgb, 30, 41, 59), 0.8);
    backdrop-filter: blur(10px);
}

/* ==========================================
   BUTTONS
   ========================================== */

.btn-icon {
    background: transparent;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    padding: 0.5rem;
    border-radius: var(--border-radius);
    transition: all var(--transition-speed) ease;
    font-size: 1.1rem;
}

.btn-icon:hover {
    background-color: var(--bg-tertiary);
    color: var(--accent-primary);
    transform: scale(1.1);
}

.btn-icon:active {
    transform: scale(0.95);
}

.btn-primary {
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
    color: white;
    border: none;
    padding: 0.75rem 1.5rem;
    border-radius: var(--border-radius);
    cursor: pointer;
    font-weight: 600;
    transition: all var(--transition-speed) ease;
    box-shadow: 0 4px 6px var(--shadow-color);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 12px var(--shadow-color);
}

.btn-primary:active {
    transform: translateY(0);
}

.btn-secondary {
    background-color: var(--bg-tertiary);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
    padding: 0.75rem 1.5rem;
    border-radius: var(--border-radius);
    cursor: pointer;
    font-weight: 600;
    transition: all var(--transition-speed) ease;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
}

.btn-secondary:hover {
    background-color: var(--accent-primary);
    color: white;
    border-color: var(--accent-primary);
    transform: translateY(-2px);
}

/* ==========================================
   THEME SWITCHER
   ========================================== */

.theme-switcher {
    position: relative;
}

.theme-menu {
    position: absolute;
    top: calc(100% + 0.5rem);
    right: 0;
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 0.5rem;
    min-width: 160px;
    box-shadow: 0 10px 25px var(--shadow-color);
    z-index: 1000;
    animation: fadeIn 0.3s ease;
}

.theme-menu.hidden {
    display: none;
}

.theme-option {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    width: 100%;
    padding: 0.75rem 1rem;
    background: transparent;
    border: none;
    color: var(--text-primary);
    cursor: pointer;
    border-radius: var(--border-radius);
    transition: all var(--transition-speed) ease;
    font-size: 0.95rem;
}

.theme-option:hover {
    background-color: var(--bg-tertiary);
    color: var(--accent-primary);
    transform: translateX(5px);
}

/* ==========================================
   MAIN LAYOUT
   ========================================== */

.main-layout {
    display: flex;
    margin-top: var(--header-height);
    min-height: calc(100vh - var(--header-height));
}

/* ==========================================
   SIDEBAR
   ========================================== */

.sidebar {
    width: var(--sidebar-width);
    background-color: var(--bg-secondary);
    border-right: 1px solid var(--border-color);
    position: fixed;
    left: 0;
    top: var(--header-height);
    bottom: 0;
    overflow-y: auto;
    transition: transform var(--transition-speed) ease;
    z-index: 30;
    animation: slideInLeft 0.5s ease;
}

.sidebar-content {
    padding: 1.5rem;
}

.sidebar-nav {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.sidebar-category {
    margin-bottom: 1rem;
}

.sidebar-category-header {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.75rem 1rem;
    background-color: var(--bg-tertiary);
    border-radius: var(--border-radius);
    cursor: pointer;
    font-weight: 600;
    color: var(--text-primary);
    transition: all var(--transition-speed) ease;
    user-select: none;
}

.sidebar-category-header:hover {
    background-color: var(--accent-primary);
    color: white;
    transform: translateX(5px);
}

.category-toggle {
    margin-left: auto;
    transition: transform var(--transition-speed) ease;
}

.sidebar-category.collapsed .category-toggle {
    transform: rotate(-90deg);
}

.sidebar-category-items {
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
    margin-top: 0.5rem;
    margin-left: 1rem;
    padding-left: 1rem;
    border-left: 2px solid var(--border-color);
    transition: all var(--transition-speed) ease;
}

.sidebar-category.collapsed .sidebar-category-items {
    display: none;
}

.sidebar-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.75rem 1rem;
    color: var(--text-secondary);
    text-decoration: none;
    border-radius: var(--border-radius);
    transition: all var(--transition-speed) ease;
    position: relative;
    overflow: hidden;
}

.sidebar-item::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    height: 100%;
    width: 3px;
    background: var(--accent-primary);
    transform: scaleY(0);
    transition: transform var(--transition-speed) ease;
}

.sidebar-item:hover::before,
.sidebar-item.active::before {
    transform: scaleY(1);
}

.sidebar-item:hover {
    background-color: var(--bg-tertiary);
    color: var(--accent-primary);
    transform: translateX(5px);
}

.sidebar-item.active {
    background-color: var(--bg-tertiary);
    color: var(--accent-primary);
    font-weight: 600;
}

/* Mobile Sidebar */
@media (max-width: 1024px) {
    .sidebar {
        transform: translateX(-100%);
    }

    .sidebar.active {
        transform: translateX(0);
    }
}

/* ==========================================
   CONTENT AREA
   ========================================== */

.content-area {
    flex: 1;
    margin-left: var(--sidebar-width);
    padding: 2rem;
    max-width: calc(100% - var(--sidebar-width) - var(--toc-width));
    animation: fadeIn 0.5s ease;
}

@media (max-width: 1024px) {
    .content-area {
        margin-left: 0;
        max-width: 100%;
    }
}

/* ==========================================
   ARTICLE CONTENT
   ========================================== */

.article-content {
    background-color: var(--bg-secondary);
    border-radius: var(--border-radius);
    padding: 2.5rem;
    box-shadow: 0 4px 6px var(--shadow-color);
    animation: fadeIn 0.5s ease;
}

.article-header {
    margin-bottom: 2rem;
    padding-bottom: 1.5rem;
    border-bottom: 2px solid var(--border-color);
}

.article-title {
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: 1rem;
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
    background-size: 200% 200%;
    animation: gradient 3s ease infinite;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.article-meta {
    display: flex;
    gap: 1.5rem;
    color: var(--text-muted);
    font-size: 0.9rem;
    margin-bottom: 1rem;
}

.article-meta i {
    margin-right: 0.5rem;
}

.article-body {
    line-height: 1.8;
    color: var(--text-secondary);
}

/* ==========================================
   MARKDOWN CONTENT STYLES
   ========================================== */

.markdown-content h1,
.markdown-content h2,
.markdown-content h3,
.markdown-content h4,
.markdown-content h5,
.markdown-content h6 {
    color: var(--text-primary);
    font-weight: 700;
    margin: 2rem 0 1rem;
    line-height: 1.3;
    scroll-margin-top: calc(var(--header-height) + 2rem);
}

.markdown-content h1 {
    font-size: 2.25rem;
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 0.5rem;
}

.markdown-content h2 {
    font-size: 1.875rem;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 0.5rem;
}

.markdown-content h3 {
    font-size: 1.5rem;
}

.markdown-content h4 {
    font-size: 1.25rem;
}

.markdown-content p {
    margin-bottom: 1.5rem;
}

.markdown-content a {
    color: var(--accent-primary);
    text-decoration: none;
    border-bottom: 1px solid transparent;
    transition: all var(--transition-speed) ease;
}

.markdown-content a:hover {
    border-bottom-color: var(--accent-primary);
}

.markdown-content ul,
.markdown-content ol {
    margin-left: 2rem;
    margin-bottom: 1.5rem;
}

.markdown-content li {
    margin-bottom: 0.5rem;
}

.markdown-content code {
    background-color: var(--code-bg);
    padding: 0.2rem 0.4rem;
    border-radius: 4px;
    font-family: 'Monaco', 'Courier New', monospace;
    font-size: 0.9em;
}

.markdown-content pre {
    background-color: var(--code-bg);
    padding: 1.5rem;
    border-radius: var(--border-radius);
    overflow-x: auto;
    margin-bottom: 1.5rem;
    border: 1px solid var(--border-color);
}

.markdown-content pre code {
    background: transparent;
    padding: 0;
}

.markdown-content blockquote {
    border-left: 4px solid var(--accent-primary);
    padding-left: 1.5rem;
    margin: 1.5rem 0;
    font-style: italic;
    color: var(--text-muted);
}

.markdown-content table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 1.5rem;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    overflow: hidden;
}

.markdown-content th,
.markdown-content td {
    padding: 0.75rem 1rem;
    border: 1px solid var(--border-color);
    text-align: left;
}

.markdown-content th {
    background-color: var(--bg-tertiary);
    font-weight: 600;
    color: var(--text-primary);
}

.markdown-content img {
    max-width: 100%;
    height: auto;
    border-radius: var(--border-radius);
    margin: 1.5rem 0;
    box-shadow: 0 4px 6px var(--shadow-color);
}

.markdown-content hr {
    border: none;
    height: 2px;
    background: var(--border-color);
    margin: 2rem 0;
}

/* ==========================================
   TABLE OF CONTENTS
   ========================================== */

.toc-sidebar {
    position: fixed;
    right: 2rem;
    top: calc(var(--header-height) + 2rem);
    width: var(--toc-width);
    max-height: calc(100vh - var(--header-height) - 4rem);
    overflow-y: auto;
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 1.5rem;
    animation: slideInRight 0.5s ease;
}

.toc-header {
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 1rem;
    font-size: 0.875rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.toc-nav {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.toc-link {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.875rem;
    padding: 0.5rem;
    border-left: 2px solid transparent;
    transition: all var(--transition-speed) ease;
}

.toc-link:hover {
    color: var(--accent-primary);
    border-left-color: var(--accent-primary);
    padding-left: 1rem;
}

.toc-link.active {
    color: var(--accent-primary);
    border-left-color: var(--accent-primary);
    font-weight: 600;
}

.toc-link.level-3 {
    margin-left: 1rem;
}

.toc-link.level-4 {
    margin-left: 2rem;
}

@media (max-width: 1400px) {
    .toc-sidebar {
        display: none;
    }
    
    .content-area {
        max-width: calc(100% - var(--sidebar-width));
    }
}

/* ==========================================
   MODALS
   ========================================== */

.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 9999;
    display: flex;
    align-items: center;
    justify-content: center;
    animation: fadeIn 0.3s ease;
}

.modal.hidden {
    display: none;
}

.modal-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.7);
    backdrop-filter: blur(5px);
}

.modal-content {
    position: relative;
    background-color: var(--bg-secondary);
    border-radius: var(--border-radius);
    max-width: 600px;
    width: 90%;
    max-height: 80vh;
    overflow: hidden;
    box-shadow: 0 20px 60px var(--shadow-color);
    animation: fadeIn 0.3s ease;
    z-index: 10000;
}

.modal-content.search-modal {
    max-width: 700px;
}

.modal-header {
    padding: 1.5rem;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.modal-close {
    background: transparent;
    border: none;
    color: var(--text-secondary);
    font-size: 1.5rem;
    cursor: pointer;
    padding: 0.5rem;
    border-radius: var(--border-radius);
    transition: all var(--transition-speed) ease;
}

.modal-close:hover {
    background-color: var(--bg-tertiary);
    color: var(--accent-primary);
    transform: rotate(90deg);
}

.modal-body {
    padding: 1.5rem;
    overflow-y: auto;
    max-height: calc(80vh - 80px);
}

/* ==========================================
   SEARCH
   ========================================== */

.search-input {
    width: 100%;
    padding: 1rem 1.5rem;
    background-color: var(--bg-tertiary);
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius);
    color: var(--text-primary);
    font-size: 1.1rem;
    transition: all var(--transition-speed) ease;
}

.search-input:focus {
    outline: none;
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.search-results {
    margin-top: 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.search-result-item {
    padding: 1rem;
    background-color: var(--bg-tertiary);
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: all var(--transition-speed) ease;
    border: 1px solid transparent;
}

.search-result-item:hover {
    background-color: var(--accent-primary);
    color: white;
    transform: translateX(5px);
    border-color: var(--accent-primary);
}

.search-result-title {
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.search-result-excerpt {
    font-size: 0.9rem;
    color: var(--text-muted);
}

.search-result-item:hover .search-result-excerpt {
    color: rgba(255, 255, 255, 0.8);
}

.search-highlight {
    background-color: var(--search-highlight);
    color: var(--bg-primary);
    padding: 0.1rem 0.3rem;
    border-radius: 3px;
    font-weight: 600;
}

/* ==========================================
   SHARE
   ========================================== */

.share-options {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: var(--text-primary);
}

.input-group {
    display: flex;
    gap: 0.5rem;
}

.share-link-input {
    flex: 1;
    padding: 0.75rem;
    background-color: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    color: var(--text-primary);
    font-family: 'Monaco', 'Courier New', monospace;
    font-size: 0.9rem;
}

.share-link-input:focus {
    outline: none;
    border-color: var(--accent-primary);
}

/* ==========================================
   EMPTY STATE
   ========================================== */

.empty-state {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 50vh;
    text-align: center;
    animation: fadeIn 0.5s ease;
}

.empty-state i {
    font-size: 5rem;
    color: var(--accent-primary);
    margin-bottom: 1.5rem;
    animation: float 3s ease-in-out infinite;
}

.empty-state h2 {
    font-size: 2rem;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.empty-state p {
    color: var(--text-secondary);
    font-size: 1.1rem;
}

.empty-state a {
    color: var(--accent-primary);
    text-decoration: none;
    border-bottom: 1px solid var(--accent-primary);
    transition: all var(--transition-speed) ease;
}

.empty-state a:hover {
    color: var(--accent-secondary);
    border-bottom-color: var(--accent-secondary);
}

/* ==========================================
   SCROLLBAR
   ========================================== */

::-webkit-scrollbar {
    width: 10px;
    height: 10px;
}

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

::-webkit-scrollbar-thumb {
    background: var(--bg-tertiary);
    border-radius: 5px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--accent-primary);
}

/* ==========================================
   LOADING ANIMATION
   ========================================== */

.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid var(--border-color);
    border-radius: 50%;
    border-top-color: var(--accent-primary);
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}

/* ==========================================
   RESPONSIVE DESIGN
   ========================================== */

@media (max-width: 768px) {
    .container-custom {
        padding: 0 1rem;
    }

    .article-content {
        padding: 1.5rem;
    }

    .article-title {
        font-size: 1.75rem;
    }

    .content-area {
        padding: 1rem;
    }

    .modal-content {
        width: 95%;
    }
}

/* ==========================================
   PRINT STYLES
   ========================================== */

@media print {
    .sidebar,
    .toc-sidebar,
    header,
    .btn-secondary,
    .modal {
        display: none !important;
    }

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

    .article-content {
        box-shadow: none;
    }
}