/* Button Components */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-sm) var(--spacing-lg);
    font-size: var(--font-size-base);
    font-weight: 500;
    text-decoration: none;
    border-radius: var(--radius-md);
    border: 2px solid transparent;
    transition: all var(--transition-fast);
    cursor: pointer;
    min-width: 120px;
    text-align: center;
}

.btn-primary {
    background-color: var(--color-primary);
    color: var(--color-text-light);
    border-color: var(--color-primary);
}

.btn-primary:hover {
    background-color: var(--color-primary-dark);
    border-color: var(--color-primary-dark);
    text-decoration: none;
    color: var(--color-text-light);
}

.btn-secondary {
    background-color: transparent;
    color: var(--color-primary);
    border-color: var(--color-primary);
}

.btn-secondary:hover {
    background-color: var(--color-primary);
    color: var(--color-text-light);
    text-decoration: none;
}

.btn-small {
    padding: var(--spacing-xs) var(--spacing-md);
    font-size: var(--font-size-sm);
    min-width: 80px;
}

/* Header and Navigation */
.main-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background-color: var(--color-bg-primary);
    border-bottom: 1px solid var(--color-border);
    z-index: 1000;
    height: var(--header-height);
}

.navbar {
    height: 100%;
}

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

.nav-brand h1 {
    font-size: var(--font-size-xl);
    color: var(--color-text-primary);
    margin: 0;
}

.nav-menu {
    display: flex;
    align-items: center;
    list-style: none;
    margin: 0;
    padding: 0;
    gap: var(--spacing-lg);
}

.nav-item {
    position: relative;
}

.nav-link {
    display: block;
    padding: var(--spacing-sm) var(--spacing-md);
    color: var(--color-text-primary);
    font-weight: 500;
    transition: color var(--transition-fast);
}

.nav-link:hover {
    color: var(--color-primary);
    text-decoration: none;
}

/* Dropdown Menu */
.dropdown {
    position: relative;
}

.dropdown-menu {
    position: absolute;
    top: 100%;
    left: 0;
    background-color: var(--color-bg-primary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-lg);
    min-width: 200px;
    padding: var(--spacing-sm) 0;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: all var(--transition-fast);
    list-style: none;
    margin: 0;
    z-index: 1001;
}

.dropdown:hover .dropdown-menu {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.dropdown-menu li {
    margin: 0;
}

.dropdown-menu a {
    display: block;
    padding: var(--spacing-sm) var(--spacing-md);
    color: var(--color-text-secondary);
    transition: all var(--transition-fast);
}

.dropdown-menu a:hover {
    background-color: var(--color-bg-secondary);
    color: var(--color-primary);
    text-decoration: none;
}

/* Mobile Navigation Toggle */
.nav-toggle {
    display: none;
    flex-direction: column;
    width: 30px;
    height: 24px;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 0;
}

.nav-toggle span {
    display: block;
    width: 100%;
    height: 3px;
    background-color: var(--color-text-primary);
    margin: 3px 0;
    transition: all var(--transition-fast);
}

.nav-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(6px, 6px);
}

.nav-toggle.active span:nth-child(2) {
    opacity: 0;
}

.nav-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(6px, -6px);
}

/* Theme Toggle */
.theme-toggle {
    background: var(--color-bg-secondary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    padding: var(--spacing-sm);
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-fast);
}

.theme-toggle:hover {
    background: var(--color-bg-tertiary);
}

.theme-icon {
    font-size: var(--font-size-lg);
}

/* Main Content */
.main-content {
    margin-top: var(--header-height);
    min-height: calc(100vh - var(--header-height));
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, var(--color-bg-primary) 0%, var(--color-bg-secondary) 100%);
    padding: var(--spacing-3xl) 0;
    min-height: 600px;
    display: flex;
    align-items: center;
}

.hero-container {
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-3xl);
    align-items: center;
}

.hero-content {
    max-width: 600px;
}

.hero-title {
    font-size: var(--font-size-5xl);
    font-weight: 700;
    margin-bottom: var(--spacing-lg);
    color: var(--color-text-primary);
    line-height: 1.1;
}

.hero-subtitle {
    font-size: var(--font-size-xl);
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-2xl);
    line-height: var(--line-height-relaxed);
}

.hero-actions {
    display: flex;
    gap: var(--spacing-md);
    flex-wrap: wrap;
}

/* Hero Visual - Code Preview */
.hero-visual {
    display: flex;
    justify-content: center;
}

.code-preview {
    background: var(--color-bg-primary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
    overflow: hidden;
    max-width: 500px;
    width: 100%;
}

.code-header {
    background: var(--color-bg-tertiary);
    padding: var(--spacing-sm) var(--spacing-md);
    border-bottom: 1px solid var(--color-border);
    font-size: var(--font-size-sm);
    font-weight: 600;
    color: var(--color-text-secondary);
}

.code-content {
    padding: var(--spacing-lg);
    font-family: var(--font-family-mono);
    font-size: var(--font-size-sm);
    line-height: 1.6;
}

.code-before,
.code-after {
    margin-bottom: var(--spacing-md);
}

.code-arrow {
    text-align: center;
    font-size: var(--font-size-2xl);
    color: var(--color-primary);
    margin: var(--spacing-md) 0;
    font-weight: bold;
}

/* Code Syntax Highlighting */
.comment { color: #999; }
.keyword { color: #007acc; }
.method { color: #e74c3c; }
.string { color: #27ae60; }
.property { color: #f39c12; }
.function { color: #8e44ad; }
.tag { color: #e74c3c; }

/* Section Styles */
section {
    padding: var(--spacing-3xl) 0;
}

.why-react {
    background-color: var(--color-bg-secondary);
}

.benefits-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
    margin-top: var(--spacing-2xl);
}

.benefit-card {
    background: var(--color-bg-primary);
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
    text-align: center;
    border: 1px solid var(--color-border);
    transition: all var(--transition-normal);
}

.benefit-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.benefit-icon {
    font-size: var(--font-size-4xl);
    margin-bottom: var(--spacing-md);
    display: block;
}

.benefit-card h3 {
    color: var(--color-text-primary);
    margin-bottom: var(--spacing-sm);
}

.benefit-card p {
    color: var(--color-text-secondary);
    margin: 0;
}

/* Learning Path */
.learning-path {
    background: var(--color-bg-primary);
}

.path-steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-xl);
    margin-top: var(--spacing-2xl);
}

.step {
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-md);
}

.step-number {
    width: 60px;
    height: 60px;
    background: var(--color-primary);
    color: var(--color-text-light);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: var(--font-size-2xl);
    font-weight: bold;
    flex-shrink: 0;
}

.step-content h3 {
    margin-bottom: var(--spacing-sm);
    color: var(--color-text-primary);
}

.step-content p {
    margin-bottom: var(--spacing-md);
    color: var(--color-text-secondary);
}

.step-link {
    display: inline-flex;
    align-items: center;
    color: var(--color-primary);
    font-weight: 500;
    text-decoration: none;
    transition: color var(--transition-fast);
}

.step-link:hover {
    color: var(--color-primary-dark);
    text-decoration: underline;
}

/* Featured Sections */
.featured-sections {
    background: var(--color-bg-secondary);
}

.sections-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-lg);
    margin-top: var(--spacing-2xl);
}

.section-card {
    background: var(--color-bg-primary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    transition: all var(--transition-normal);
}

.section-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

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

.card-header h3 {
    margin: 0;
    color: var(--color-text-primary);
}

.difficulty {
    background: var(--color-bg-tertiary);
    color: var(--color-text-secondary);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-sm);
    font-size: var(--font-size-xs);
    font-weight: 600;
    text-transform: uppercase;
}

.section-card p {
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-lg);
}

.card-link {
    color: var(--color-primary);
    font-weight: 500;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    transition: color var(--transition-fast);
}

.card-link:hover {
    color: var(--color-primary-dark);
    text-decoration: underline;
}

/* Footer */
.main-footer {
    background: var(--color-bg-footer-dark);
    border-top: 1px solid var(--color-border);
    padding: var(--spacing-3xl) 0 var(--spacing-lg);
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-2xl);
}

.footer-section h3,
.footer-section h4 {
    color: var(--color-text-light);
    margin-bottom: var(--spacing-md);
}

.footer-section p {
    color: #adb5bd;
    margin: 0;
}

.footer-section ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.footer-section ul li {
    margin-bottom: var(--spacing-sm);
}

.footer-section ul a {
    color: #adb5bd;
    text-decoration: none;
    transition: color var(--transition-fast);
}

.footer-section ul a:hover {
    color: var(--color-primary);
}

.footer-bottom {
    border-top: 1px solid #495057;
    padding-top: var(--spacing-lg);
    text-align: center;
}

.footer-bottom p {
    color: #adb5bd;
    margin: 0;
    font-size: var(--font-size-sm);
}

/* Animations */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in-up {
    animation: fadeInUp 0.6s ease-out;
}

/* Loading States */
.loading {
    opacity: 0.6;
    pointer-events: none;
}

.loading::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 20px;
    height: 20px;
    margin: -10px 0 0 -10px;
    border: 2px solid var(--color-border);
    border-top: 2px solid var(--color-primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* Code Display Components */
.code-example {
    background: var(--color-bg-secondary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    margin: var(--spacing-md) 0;
    overflow: hidden;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.code-header {
    background: var(--color-bg-tertiary);
    padding: var(--spacing-sm) var(--spacing-md);
    border-bottom: 1px solid var(--color-border);
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
}

.code-lang {
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    color: var(--color-primary);
}

.code-actions {
    display: flex;
    gap: var(--spacing-sm);
}

.copy-button {
    background: none;
    border: 1px solid var(--color-border);
    border-radius: 4px;
    padding: 4px 8px;
    font-size: var(--font-size-xs);
    color: var(--color-text-secondary);
    cursor: pointer;
    transition: all 0.2s ease;
}

.copy-button:hover {
    background: var(--color-primary);
    color: white;
    border-color: var(--color-primary);
}

.code-example pre {
    margin: 0;
    padding: var(--spacing-md);
    overflow-x: auto;
    background: transparent;
    font-family: 'Fira Code', 'JetBrains Mono', 'Courier New', Consolas, Monaco, monospace;
    font-size: var(--font-size-sm);
    line-height: 1.6;
    white-space: pre-wrap;
    word-wrap: break-word;
}

.code-example code {
    background: transparent;
    padding: 0;
    color: var(--color-text-primary);
    display: block;
}

/* Syntax Highlighting */
.code-keyword { color: #569cd6; }
.code-string { color: #ce9178; }
.code-comment { color: #6a9955; }
.code-number { color: #b5cea8; }
.code-function { color: #dcdcaa; }
.code-tag { color: #569cd6; }
.code-attribute { color: #9cdcfe; }

/* Dark theme syntax highlighting */
.dark-theme .code-keyword { color: #c586c0; }
.dark-theme .code-string { color: #ce9178; }
.dark-theme .code-comment { color: #6a9955; }
.dark-theme .code-number { color: #b5cea8; }
.dark-theme .code-function { color: #dcdcaa; }
.dark-theme .code-tag { color: #569cd6; }
.dark-theme .code-attribute { color: #9cdcfe; }

/* Comparison Layout */
.comparison-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-lg);
    margin: var(--spacing-lg) 0;
}

.comparison-side {
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    overflow: hidden;
}

.comparison-header {
    background: var(--color-bg-tertiary);
    padding: var(--spacing-sm) var(--spacing-md);
    font-weight: 600;
    text-align: center;
    border-bottom: 1px solid var(--color-border);
}

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

/* Comparison Table */
.comparison-table {
    margin: var(--spacing-lg) 0;
    overflow-x: auto;
}

.comparison-table table {
    width: 100%;
    border-collapse: collapse;
    background: var(--color-bg-primary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    overflow: hidden;
}

.comparison-table th,
.comparison-table td {
    padding: var(--spacing-md);
    text-align: left;
    border-bottom: 1px solid var(--color-border);
}

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

.comparison-table td {
    color: var(--color-text-secondary);
}

.comparison-table tr:last-child td {
    border-bottom: none;
}

/* Example Comparison */
.example-comparison {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-lg);
    margin: var(--spacing-lg) 0;
}

.example-column h3 {
    text-align: center;
    margin-bottom: var(--spacing-md);
    padding: var(--spacing-sm);
    background: var(--color-bg-tertiary);
    border-radius: var(--radius-md) var(--radius-md) 0 0;
    border: 1px solid var(--color-border);
    border-bottom: none;
}

/* Next Steps */
.next-steps {
    display: flex;
    gap: var(--spacing-md);
    margin-top: var(--spacing-lg);
    flex-wrap: wrap;
}

/* Sidebar sections */
.sidebar-section {
    margin-bottom: var(--spacing-lg);
}

.sidebar-section:last-child {
    margin-bottom: 0;
}

.sidebar-section h3 {
    font-size: var(--font-size-lg);
    margin-bottom: var(--spacing-md);
    color: var(--color-text-primary);
    border-bottom: 1px solid var(--color-border);
    padding-bottom: var(--spacing-xs);
}

.section-nav ul,
.related-links {
    list-style: none;
    padding: 0;
    margin: 0;
}

.section-nav li,
.related-links li {
    margin-bottom: var(--spacing-sm);
}

.section-nav a,
.related-links a {
    color: var(--color-text-secondary);
    text-decoration: none;
    font-size: var(--font-size-sm);
    transition: color var(--transition-fast);
    display: block;
    padding: var(--spacing-xs) 0;
}

.section-nav a:hover,
.related-links a:hover {
    color: var(--color-primary);
}

.quick-ref h4 {
    font-size: var(--font-size-base);
    margin-bottom: var(--spacing-sm);
    color: var(--color-text-primary);
}

.quick-ref ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.quick-ref li {
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-xs);
    padding-left: var(--spacing-md);
    position: relative;
}

.quick-ref li::before {
    content: '•';
    position: absolute;
    left: 0;
    color: var(--color-primary);
}

/* What Makes React Special Cards */
.special-features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-lg);
    margin: var(--spacing-xl) 0;
}

.feature-card {
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
    color: white;
    text-align: center;
    position: relative;
    overflow: hidden;
    transition: transform var(--transition-normal);
}

.feature-card:hover {
    transform: translateY(-5px);
}

.feature-card.developer {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

.feature-card.performance {
    background: var(--color-green-feature);
}

.feature-card.industry {
    background: var(--color-purple-pink-feature);
}

.feature-card.versatile {
    background: var(--color-orange-yellow-feature);
}

.feature-card h3 {
    margin-bottom: var(--spacing-md);
    font-size: var(--font-size-xl);
    color: white;
}

.feature-card p {
    color: rgba(255, 255, 255, 0.9);
    margin: 0;
    line-height: var(--line-height-relaxed);
}

/* Ready to Start Learning Section */
.ready-section {
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-dark) 100%);
    color: white;
    padding: var(--spacing-3xl) 0;
    text-align: center;
    margin: var(--spacing-3xl) 0;
    border-radius: var(--radius-lg);
}

.ready-section h2 {
    color: white;
    margin-bottom: var(--spacing-md);
    font-size: var(--font-size-3xl);
}

.ready-section p {
    color: rgba(255, 255, 255, 0.9);
    font-size: var(--font-size-lg);
    margin-bottom: var(--spacing-xl);
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.ready-section .next-steps {
    justify-content: center;
}

.ready-section .btn {
    background: rgba(255, 255, 255, 0.2);
    border-color: rgba(255, 255, 255, 0.3);
    color: white;
    backdrop-filter: blur(10px);
}

.ready-section .btn:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: translateY(-2px);
}

.ready-section .btn-primary {
    background-color: var(--color-primary);
    color: var(--color-text-light);
    border-color: var(--color-primary);
}

.ready-section .btn-primary:hover {
    background-color: var(--color-primary-dark);
    border-color: var(--color-primary-dark);
    color: var(--color-text-light);
}

.ready-section .btn-secondary {
    background-color: var(--color-bg-button-secondary-cta);
    color: var(--color-text-primary);
    border-color: var(--color-border);
}

.ready-section .btn-secondary:hover {
    background-color: #d3d9df;
    color: var(--color-text-primary);
    border-color: var(--color-border);
}

/* Content Layout Components */
.content-layout {
    display: grid;
    grid-template-columns: 1fr 250px;
    gap: var(--spacing-xl);
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

.main-content-area {
    min-width: 0; /* Prevents overflow */
}

.sidebar {
    position: sticky;
    top: calc(var(--header-height) + var(--spacing-md));
    height: fit-content;
    background: var(--color-bg-secondary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    padding: var(--spacing-md);
}

.sidebar-title {
    font-size: var(--font-size-lg);
    font-weight: 600;
    margin-bottom: var(--spacing-md);
    color: var(--color-text-primary);
}

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

.sidebar-nav li {
    margin-bottom: var(--spacing-sm);
}

.sidebar-nav a {
    color: var(--color-text-secondary);
    text-decoration: none;
    font-size: var(--font-size-sm);
    transition: color 0.2s ease;
    display: block;
    padding: var(--spacing-xs) 0;
}

.sidebar-nav a:hover,
.sidebar-nav a.active {
    color: var(--color-primary);
}

/* Content Blocks */
.content-block {
    margin-bottom: var(--spacing-xl);
}

.content-block h2 {
    margin-bottom: var(--spacing-md);
    color: var(--color-text-primary);
    border-bottom: 2px solid var(--color-primary);
    padding-bottom: var(--spacing-xs);
}

.content-block h3 {
    margin: var(--spacing-lg) 0 var(--spacing-md) 0;
    color: var(--color-text-primary);
}

/* Concept Grid */
.concept-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-md);
    margin: var(--spacing-lg) 0;
}

.concept-card {
    background: var(--color-bg-secondary);
    padding: var(--spacing-lg);
    border-radius: var(--radius-md);
    border: 1px solid var(--color-border);
    text-align: center;
}

.concept-card h3 {
    margin-bottom: var(--spacing-md);
    color: var(--color-text-primary);
    font-size: var(--font-size-lg);
}

/* Explanation Boxes */
.explanation-box {
    background: var(--color-bg-secondary);
    border: 1px solid var(--color-border);
    padding: var(--spacing-lg);
    margin: var(--spacing-lg) 0;
    border-radius: var(--radius-md);
}

.explanation-box h3 {
    margin-top: 0;
    margin-bottom: var(--spacing-md);
    color: var(--color-primary);
}

/* Highlight Quote */
.highlight-quote {
    background: var(--color-bg-secondary);
    border-left: 4px solid var(--color-primary);
    padding: var(--spacing-lg);
    margin: var(--spacing-lg) 0;
    font-style: italic;
    font-size: var(--font-size-lg);
    line-height: 1.6;
}

.highlight-quote footer {
    margin-top: var(--spacing-md);
    font-style: normal;
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
}

/* Page Header */
.page-header {
    background: var(--color-bg-page-header);
    color: var(--color-text-primary);
    padding: var(--spacing-xl) 0;
    margin-bottom: var(--spacing-xl);
}

.page-header-content {
    text-align: center;
    max-width: 800px;
    margin: 0 auto;
}

.page-header h1 {
    font-size: var(--font-size-3xl);
    margin-bottom: var(--spacing-md);
    color: var(--color-text-primary);
}

.page-subtitle {
    font-size: var(--font-size-lg);
    margin-bottom: var(--spacing-lg);
    color: var(--color-text-secondary);
    opacity: 1;
    line-height: 1.6;
}

.page-meta {
    display: flex;
    justify-content: center;
    gap: var(--spacing-md);
    align-items: center;
}

.difficulty-badge {
    background: rgba(255, 255, 255, 0.2);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: 20px;
    font-size: var(--font-size-sm);
    font-weight: 500;
}

.difficulty-badge.beginner {
    background: rgba(76, 175, 80, 0.2);
    color: #0d0d0d;
}

.difficulty-badge.intermediate {
    background: rgba(255, 152, 0, 0.2);
    color: #b85c00;
}

.difficulty-badge.advanced {
    background: rgba(244, 67, 54, 0.2);
    color: #a02018;
}

.reading-time {
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
    opacity: 1;
}

/* Breadcrumbs */
.breadcrumbs {
    background: var(--color-bg-secondary);
    padding: var(--spacing-sm) 0;
    border-bottom: 1px solid var(--color-border);
}

.breadcrumb-link {
    color: var(--color-text-secondary);
    text-decoration: none;
    font-size: var(--font-size-sm);
    transition: color 0.2s ease;
}

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

.breadcrumb-separator {
    margin: 0 var(--spacing-sm);
    color: var(--color-text-secondary);
}

.breadcrumb-current {
    color: var(--color-text-primary);
    font-weight: 500;
    font-size: var(--font-size-sm);
}

/* Company Grid for Why Learn React page */
.company-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-lg);
    margin: var(--spacing-lg) 0;
}

.company-category h4 {
    color: var(--color-primary);
    margin-bottom: var(--spacing-md);
    font-size: var(--font-size-lg);
    border-bottom: 1px solid var(--color-border);
    padding-bottom: var(--spacing-xs);
}

.company-category ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.company-category li {
    margin-bottom: var(--spacing-sm);
    padding-left: var(--spacing-md);
    position: relative;
}

.company-category li::before {
    content: '🏢';
    position: absolute;
    left: 0;
    top: 0;
}

.company-category strong {
    color: var(--color-text-primary);
    font-weight: 600;
}

/* Responsive adjustments for content pages */
@media (max-width: 768px) {
    .content-layout {
        grid-template-columns: 1fr;
        gap: var(--spacing-lg);
    }
    
    .sidebar {
        position: static;
        order: -1;
    }
    
    .comparison-container {
        grid-template-columns: 1fr;
    }
    
    .company-grid {
        grid-template-columns: 1fr;
    }
    
    .concept-grid {
        grid-template-columns: 1fr;
    }
    
    .example-comparison {
        grid-template-columns: 1fr;
    }
    
    .next-steps {
        flex-direction: column;
        align-items: stretch;
    }
    
    .next-steps .btn {
        text-align: center;
    }
    
    .special-features {
        grid-template-columns: 1fr;
        gap: var(--spacing-md);
    }
    
    .ready-section {
        margin: var(--spacing-xl) 0;
        padding: var(--spacing-xl) 0;
    }
    
    .ready-section h2 {
        font-size: var(--font-size-2xl);
    }
}