/* ================================================================
   YouTube International Blog - Design System
   Philosophy: Swiss International Style meets Cyber-Minimalism
   ================================================================ */

/* --- CSS Variables (Design Tokens) --- */
:root {
    /* Typography */
    --font-primary: 'Noto Sans', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', monospace;

    /* Light Mode Colors */
    --bg-primary: #ffffff;
    --bg-secondary: #f8fafc;
    --bg-tertiary: #f1f5f9;
    --text-primary: #0f172a;
    --text-secondary: #475569;
    --text-muted: #94a3b8;
    --border-color: #e2e8f0;

    /* Brand Colors */
    --accent-primary: #2563EB;      /* Royal Blue - Trust/Tech */
    --accent-primary-hover: #1d4ed8;
    --accent-secondary: #10B981;    /* Emerald - Money/Affiliate */
    --accent-secondary-hover: #059669;
    --accent-alert: #F59E0B;        /* Amber - Important */
    --accent-danger: #EF4444;       /* Red - Errors */

    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);

    /* Spacing */
    --space-xs: 0.25rem;
    --space-sm: 0.5rem;
    --space-md: 1rem;
    --space-lg: 1.5rem;
    --space-xl: 2rem;
    --space-2xl: 3rem;

    /* Border Radius */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    --radius-full: 9999px;

    /* Layout */
    --max-width: 1280px;
    --sidebar-width: 320px;
    --header-height: 64px;

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-normal: 250ms ease;
    --transition-slow: 350ms ease;
}

/* --- Dark Mode --- */
[data-theme="dark"] {
    --bg-primary: #121212;
    --bg-secondary: #1e1e1e;
    --bg-tertiary: #2d2d2d;
    --text-primary: #f1f5f9;
    --text-secondary: #cbd5e1;
    --text-muted: #64748b;
    --border-color: #374151;
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.5);
}

/* --- Base Reset --- */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-primary);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    transition: background-color var(--transition-normal), color var(--transition-normal);
}

/* --- Reading Progress Bar --- */
.reading-progress {
    position: fixed;
    top: 0;
    left: 0;
    width: 0%;
    height: 3px;
    background: linear-gradient(90deg, var(--accent-primary), var(--accent-secondary));
    z-index: 9999;
    transition: width 50ms linear;
}

/* --- Mega-Nav Header --- */
.mega-nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--header-height);
    background: var(--bg-primary);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
    box-shadow: var(--shadow-sm);
}

.mega-nav__container {
    max-width: var(--max-width);
    height: 100%;
    margin: 0 auto;
    padding: 0 var(--space-lg);
    display: grid;
    grid-template-columns: auto 1fr auto;
    align-items: center;
    gap: var(--space-xl);
}

.mega-nav__logo {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}

.mega-nav__logo:hover {
    color: var(--accent-primary);
}

.mega-nav__logo:hover .logo-icon svg {
    transform: scale(1.05);
}

/* Logo Icon */
.logo-icon {
    display: flex;
    align-items: center;
    justify-content: center;
}

.logo-icon svg {
    transition: transform var(--transition-fast);
}

/* Logo Text Styling */
.logo-text {
    display: flex;
    font-size: 1.35rem;
    font-weight: 800;
    letter-spacing: -0.02em;
}

.logo-text__vid {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.logo-text__insights {
    color: var(--text-primary);
}

[data-theme="dark"] .logo-text__insights {
    color: var(--text-primary);
}

/* Categories (Center) */
.mega-nav__categories {
    display: flex;
    justify-content: center;
    gap: var(--space-lg);
    list-style: none;
}

.mega-nav__categories a {
    display: flex;
    align-items: center;
    gap: var(--space-xs);
    padding: var(--space-sm) var(--space-md);
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
}

.mega-nav__categories a:hover,
.mega-nav__categories a.active {
    color: var(--accent-primary);
    background: rgba(37, 99, 235, 0.1);
}

/* Dropdown Arrow */
.dropdown-arrow {
    margin-left: var(--space-xs);
    transition: transform var(--transition-fast);
}

.has-dropdown:hover .dropdown-arrow {
    transform: rotate(180deg);
}

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

.dropdown-menu {
    position: absolute;
    top: 100%;
    left: 0;
    min-width: 180px;
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-lg);
    list-style: none;
    opacity: 0;
    visibility: hidden;
    transform: translateY(10px);
    transition: all var(--transition-fast);
    z-index: 100;
    padding: var(--space-sm) 0;
}

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

.dropdown-menu li a {
    display: block;
    padding: var(--space-sm) var(--space-md);
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.9rem;
    transition: all var(--transition-fast);
}

.dropdown-menu li a:hover {
    background: var(--bg-secondary);
    color: var(--accent-primary);
}

/* Right Actions */
.mega-nav__actions {
    display: flex;
    align-items: center;
    gap: var(--space-md);
}

.nav-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border: none;
    background: var(--bg-secondary);
    color: var(--text-secondary);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.nav-btn:hover {
    background: var(--bg-tertiary);
    color: var(--text-primary);
}

.nav-btn svg {
    width: 20px;
    height: 20px;
}

/* Dark Mode Toggle */
.theme-toggle {
    position: relative;
}

.theme-toggle__icon--sun { display: none; }
.theme-toggle__icon--moon { display: block; }

[data-theme="dark"] .theme-toggle__icon--sun { display: block; }
[data-theme="dark"] .theme-toggle__icon--moon { display: none; }

/* User Avatar */
.user-avatar-btn {
    width: 36px;
    height: 36px;
    border-radius: var(--radius-full);
    background: var(--accent-primary);
    color: white;
    font-weight: 600;
    font-size: 0.875rem;
}

/* --- Language Switcher Modal --- */
.lang-modal {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(4px);
    z-index: 2000;
    display: none;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: opacity var(--transition-normal);
}

.lang-modal.active {
    display: flex;
    opacity: 1;
}

.lang-modal__content {
    background: var(--bg-primary);
    border-radius: var(--radius-xl);
    padding: var(--space-xl);
    max-width: 480px;
    width: 90%;
    box-shadow: var(--shadow-xl);
}

.lang-modal__header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--space-lg);
}

.lang-modal__title {
    font-size: 1.25rem;
    font-weight: 600;
}

.lang-modal__close {
    width: 32px;
    height: 32px;
    border: none;
    background: var(--bg-secondary);
    border-radius: var(--radius-full);
    cursor: pointer;
    color: var(--text-secondary);
    transition: all var(--transition-fast);
}

.lang-modal__close:hover {
    background: var(--bg-tertiary);
    color: var(--text-primary);
}

.lang-modal__grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-sm);
}

.lang-option {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    padding: var(--space-md);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    text-decoration: none;
    color: var(--text-primary);
    transition: all var(--transition-fast);
}

.lang-option:hover {
    border-color: var(--accent-primary);
    background: rgba(37, 99, 235, 0.05);
}

.lang-option.active {
    border-color: var(--accent-primary);
    background: rgba(37, 99, 235, 0.1);
}

.lang-option__flag {
    font-size: 1.5rem;
}

.lang-option__name {
    font-weight: 500;
}

.lang-option__native {
    font-size: 0.875rem;
    color: var(--text-muted);
}

/* --- Main Layout --- */
.page-wrapper {
    margin-top: var(--header-height);
    min-height: calc(100vh - var(--header-height));
}

.main-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: var(--space-xl) var(--space-lg);
    display: grid;
    grid-template-columns: 1fr var(--sidebar-width);
    gap: var(--space-2xl);
}

/* --- Content Area --- */
.content {
    min-width: 0;
}

.article {
    background: var(--bg-primary);
    border-radius: var(--radius-lg);
}

.article__header {
    margin-bottom: var(--space-xl);
}

.article__title {
    font-size: 2.25rem;
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: var(--space-md);
}

.article__meta {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-md);
    color: var(--text-muted);
    font-size: 0.875rem;
}

.article__author {
    display: flex;
    align-items: center;
    gap: var(--space-xs);
}

.article__content {
    font-size: 1.125rem;
    line-height: 1.8;
}

.article__content h2 {
    font-size: 1.5rem;
    margin: var(--space-xl) 0 var(--space-md);
    color: var(--text-primary);
}

.article__content h3 {
    font-size: 1.25rem;
    margin: var(--space-lg) 0 var(--space-md);
}

.article__content p {
    margin-bottom: var(--space-md);
}

.article__content a {
    color: var(--accent-primary);
    text-decoration: underline;
    text-underline-offset: 2px;
}

.article__content a:hover {
    color: var(--accent-primary-hover);
}

/* Affiliate Links */
.article__content a[href*="geni.us"],
.affiliate-link {
    color: var(--accent-secondary);
    font-weight: 500;
}

.article__content a[href*="geni.us"]::after,
.affiliate-link::after {
    content: " ↗";
    font-size: 0.75em;
}

/* --- Sticky Sidebar --- */
.sidebar {
    position: sticky;
    top: calc(var(--header-height) + var(--space-xl));
    height: fit-content;
    max-height: calc(100vh - var(--header-height) - var(--space-2xl));
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: var(--space-lg);
}

.sidebar::-webkit-scrollbar {
    width: 4px;
}

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

/* Sidebar Widgets */
.widget {
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    padding: var(--space-lg);
    border: 1px solid var(--border-color);
}

.widget__title {
    font-size: 0.875rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-muted);
    margin-bottom: var(--space-md);
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}

/* Trending Widget */
.trending-list {
    list-style: none;
}

.trending-item {
    display: flex;
    gap: var(--space-md);
    padding: var(--space-sm) 0;
    border-bottom: 1px solid var(--border-color);
}

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

.trending-item__rank {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--accent-primary);
    min-width: 24px;
}

.trending-item__content {
    flex: 1;
}

.trending-item__title {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-primary);
    text-decoration: none;
    display: block;
    margin-bottom: var(--space-xs);
}

.trending-item__title:hover {
    color: var(--accent-primary);
}

.trending-item__meta {
    font-size: 0.75rem;
    color: var(--text-muted);
}

/* Newsletter Widget */
.newsletter-widget {
    background: linear-gradient(135deg, var(--accent-primary), #4f46e5);
    color: white;
    border: none;
}

.newsletter-widget .widget__title {
    color: rgba(255, 255, 255, 0.8);
}

.newsletter-widget h4 {
    font-size: 1.125rem;
    margin-bottom: var(--space-sm);
}

.newsletter-widget p {
    font-size: 0.875rem;
    opacity: 0.9;
    margin-bottom: var(--space-md);
}

.newsletter-widget input[type="email"] {
    width: 100%;
    padding: var(--space-sm) var(--space-md);
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-radius: var(--radius-md);
    background: rgba(255, 255, 255, 0.1);
    color: white;
    font-size: 0.875rem;
    margin-bottom: var(--space-sm);
}

.newsletter-widget input[type="email"]::placeholder {
    color: rgba(255, 255, 255, 0.6);
}

.newsletter-widget input[type="email"]:focus {
    outline: none;
    border-color: white;
    background: rgba(255, 255, 255, 0.2);
}

.newsletter-widget button {
    width: 100%;
    padding: var(--space-sm) var(--space-md);
    border: none;
    border-radius: var(--radius-md);
    background: white;
    color: var(--accent-primary);
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.newsletter-widget button:hover {
    background: var(--bg-secondary);
    transform: translateY(-1px);
}

/* Affiliate Product Box */
.product-widget {
    text-align: center;
}

.product-widget__image {
    width: 100%;
    aspect-ratio: 1;
    object-fit: contain;
    border-radius: var(--radius-md);
    background: var(--bg-tertiary);
    margin-bottom: var(--space-md);
}

.product-widget__name {
    font-weight: 600;
    margin-bottom: var(--space-xs);
}

.product-widget__price {
    color: var(--accent-secondary);
    font-weight: 700;
    font-size: 1.25rem;
    margin-bottom: var(--space-md);
}

.product-widget__cta {
    display: block;
    width: 100%;
    padding: var(--space-sm) var(--space-md);
    background: var(--accent-secondary);
    color: white;
    text-decoration: none;
    border-radius: var(--radius-md);
    font-weight: 600;
    transition: all var(--transition-fast);
}

.product-widget__cta:hover {
    background: var(--accent-secondary-hover);
    transform: translateY(-1px);
}

/* --- Video Embed (Lazy Loading) --- */
.video-embed {
    position: relative;
    width: 100%;
    padding-bottom: 56.25%; /* 16:9 */
    background: var(--bg-tertiary);
    border-radius: var(--radius-lg);
    overflow: hidden;
    margin: var(--space-lg) 0;
}

.video-embed__placeholder {
    position: absolute;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
}

.video-embed__placeholder img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.video-embed__play {
    position: absolute;
    width: 72px;
    height: 72px;
    background: rgba(0, 0, 0, 0.7);
    border-radius: var(--radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-fast);
}

.video-embed__play::after {
    content: "";
    border-style: solid;
    border-width: 12px 0 12px 20px;
    border-color: transparent transparent transparent white;
    margin-left: 4px;
}

.video-embed__placeholder:hover .video-embed__play {
    background: var(--accent-danger);
    transform: scale(1.1);
}

.video-embed iframe {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    border: none;
}

/* --- Comments Section --- */
.comments-container {
    margin-top: var(--space-2xl);
    padding: var(--space-xl);
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-color);
}

.comments-container h3 {
    margin-bottom: var(--space-lg);
    color: var(--text-primary);
}

#auth-box input,
#comment-box textarea {
    width: 100%;
    padding: var(--space-md);
    margin-bottom: var(--space-sm);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 1rem;
    background: var(--bg-primary);
    color: var(--text-primary);
    transition: border-color var(--transition-fast);
}

#auth-box input:focus,
#comment-box textarea:focus {
    outline: none;
    border-color: var(--accent-primary);
}

#auth-box button,
#comment-box button {
    padding: var(--space-sm) var(--space-lg);
    background: var(--accent-primary);
    color: white;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    font-size: 1rem;
    font-weight: 500;
    transition: all var(--transition-fast);
}

#auth-box button:hover,
#comment-box button:hover {
    background: var(--accent-primary-hover);
}

.comment {
    padding: var(--space-md);
    margin: var(--space-md) 0;
    background: var(--bg-primary);
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
}

.ai-reply {
    background: linear-gradient(135deg, rgba(37, 99, 235, 0.05) 0%, rgba(79, 70, 229, 0.05) 100%);
    border-left: 4px solid var(--accent-primary);
    margin-left: var(--space-lg);
}

.ai-badge {
    background: var(--accent-primary);
    color: white;
    padding: var(--space-xs) var(--space-sm);
    border-radius: var(--radius-sm);
    font-size: 0.75rem;
    font-weight: 600;
}

/* --- Auth Section --- */
.auth-container {
    max-width: 400px;
    margin: 0 auto;
}

.auth-panel {
    padding: var(--space-xl);
    background: var(--bg-primary);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--border-color);
}

.auth-panel h3 {
    margin-bottom: var(--space-lg);
    text-align: center;
    color: var(--text-primary);
}

.form-group {
    margin-bottom: var(--space-md);
}

.form-group input[type="text"],
.form-group input[type="email"],
.form-group input[type="password"] {
    width: 100%;
    padding: var(--space-md);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 1rem;
    background: var(--bg-primary);
    color: var(--text-primary);
}

.form-group input:focus {
    outline: none;
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.btn-primary {
    width: 100%;
    padding: var(--space-md);
    background: var(--accent-primary);
    color: white;
    border: none;
    border-radius: var(--radius-md);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    margin-top: var(--space-md);
    transition: all var(--transition-fast);
}

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

.btn-secondary {
    width: 100%;
    padding: var(--space-sm);
    background: var(--bg-tertiary);
    color: var(--text-secondary);
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-fast);
}

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

/* MFA Setup */
.pseudonym-reveal {
    margin: var(--space-lg) 0;
    padding: var(--space-md);
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: var(--radius-md);
    color: white;
    text-align: center;
}

.pseudonym-badge {
    display: inline-block;
    padding: var(--space-sm) var(--space-md);
    background: rgba(255, 255, 255, 0.2);
    border-radius: var(--radius-full);
    font-weight: 600;
    font-size: 1.125rem;
}

/* --- Footer --- */
.site-footer {
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    padding: var(--space-2xl) var(--space-lg);
    margin-top: var(--space-2xl);
}

.footer__container {
    max-width: var(--max-width);
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--space-xl);
}

.footer__section h4 {
    font-size: 0.875rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-muted);
    margin-bottom: var(--space-md);
}

.footer__links {
    list-style: none;
}

.footer__links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.875rem;
    display: block;
    padding: var(--space-xs) 0;
    transition: color var(--transition-fast);
}

.footer__links a:hover {
    color: var(--accent-primary);
}

.footer__bottom {
    max-width: var(--max-width);
    margin: var(--space-xl) auto 0;
    padding-top: var(--space-lg);
    border-top: 1px solid var(--border-color);
    text-align: center;
    font-size: 0.875rem;
    color: var(--text-muted);
}

/* --- Affiliate Disclosure --- */
.affiliate-disclosure {
    margin-top: var(--space-xl);
    padding: var(--space-md);
    background: var(--bg-tertiary);
    border-radius: var(--radius-md);
    font-size: 0.875rem;
    color: var(--text-muted);
    border-left: 4px solid var(--accent-alert);
}

/* --- Best Of List --- */
.bestof-section {
    margin: var(--space-2xl) 0;
}

.bestof-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: var(--space-lg);
}

.bestof-card {
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    overflow: hidden;
    border: 1px solid var(--border-color);
    transition: all var(--transition-fast);
}

.bestof-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.bestof-card__image {
    width: 100%;
    aspect-ratio: 16/9;
    object-fit: cover;
}

.bestof-card__content {
    padding: var(--space-md);
}

.bestof-card__category {
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    color: var(--accent-primary);
    margin-bottom: var(--space-xs);
}

.bestof-card__title {
    font-weight: 600;
    margin-bottom: var(--space-sm);
}

.bestof-card__cta {
    display: inline-block;
    padding: var(--space-xs) var(--space-md);
    background: var(--accent-secondary);
    color: white;
    text-decoration: none;
    border-radius: var(--radius-sm);
    font-size: 0.875rem;
    font-weight: 500;
}

/* --- Leaderboard --- */
.leaderboard {
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    padding: var(--space-lg);
    border: 1px solid var(--border-color);
}

.leaderboard__title {
    font-size: 1.125rem;
    margin-bottom: var(--space-lg);
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}

.leaderboard__list {
    list-style: none;
}

.leaderboard__item {
    display: flex;
    align-items: center;
    padding: var(--space-sm) 0;
    border-bottom: 1px solid var(--border-color);
}

.leaderboard__item:last-child {
    border-bottom: none;
}

.leaderboard__rank {
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-full);
    font-weight: 700;
    font-size: 0.875rem;
    margin-right: var(--space-md);
}

.leaderboard__rank--gold {
    background: linear-gradient(135deg, #fbbf24, #f59e0b);
    color: white;
}

.leaderboard__rank--silver {
    background: linear-gradient(135deg, #94a3b8, #64748b);
    color: white;
}

.leaderboard__rank--bronze {
    background: linear-gradient(135deg, #d97706, #b45309);
    color: white;
}

.leaderboard__pseudonym {
    flex: 1;
    font-weight: 500;
}

.leaderboard__score {
    font-weight: 600;
    color: var(--accent-alert);
}

/* --- Responsive Design --- */
@media (max-width: 1024px) {
    .main-container {
        grid-template-columns: 1fr;
    }

    .sidebar {
        position: static;
        max-height: none;
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    }
}

@media (max-width: 768px) {
    :root {
        --header-height: 56px;
    }

    .mega-nav__categories {
        display: none;
    }

    .mega-nav__container {
        grid-template-columns: auto 1fr;
    }

    .article__title {
        font-size: 1.75rem;
    }

    .lang-modal__grid {
        grid-template-columns: 1fr;
    }

    .footer__container {
        grid-template-columns: 1fr 1fr;
    }
}

@media (max-width: 480px) {
    .mega-nav__container {
        padding: 0 var(--space-md);
    }

    .main-container {
        padding: var(--space-md);
    }

    .sidebar {
        grid-template-columns: 1fr;
    }

    .footer__container {
        grid-template-columns: 1fr;
    }
}

/* ================================================================
   Education / Courses Design Extension
   ================================================================ */

:root {
    --accent-edu: #7C3AED;
    --accent-edu-hover: #6D28D9;
    --accent-edu-light: rgba(124, 58, 237, 0.08);
}

/* Section type labels */
.section-label {
    display: inline-flex;
    align-items: center;
    gap: var(--space-sm);
    padding: 0.25rem 0.75rem;
    border-radius: var(--radius-full);
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    margin-bottom: var(--space-sm);
}

.section-label--courses {
    background: var(--accent-edu-light);
    color: var(--accent-edu);
}

.section-label--roundups {
    background: rgba(37, 99, 235, 0.08);
    color: var(--accent-primary);
}

/* Course Card */
.course-card {
    background: var(--bg-primary);
    border-radius: var(--radius-xl);
    overflow: hidden;
    border: 1px solid var(--border-color);
    transition: all var(--transition-normal);
    display: flex;
    flex-direction: column;
    text-decoration: none;
    color: inherit;
}

.course-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-xl);
    border-color: var(--accent-edu);
}

.course-card__banner {
    height: 120px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
}

.course-card__banner-icon {
    font-size: 3rem;
    opacity: 0.9;
}

.course-card__level-badge {
    position: absolute;
    top: 12px;
    right: 12px;
    padding: 0.2rem 0.6rem;
    background: rgba(255, 255, 255, 0.25);
    color: white;
    border-radius: var(--radius-full);
    font-size: 0.65rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    backdrop-filter: blur(4px);
}

.course-card__content {
    padding: var(--space-lg);
    flex: 1;
    display: flex;
    flex-direction: column;
}

.course-card__tag {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    padding: 0.2rem 0.6rem;
    background: var(--accent-edu-light);
    color: var(--accent-edu);
    border-radius: var(--radius-full);
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    margin-bottom: var(--space-sm);
    width: fit-content;
}

.course-card__title {
    font-size: 1.125rem;
    font-weight: 700;
    line-height: 1.3;
    margin-bottom: var(--space-sm);
    color: var(--text-primary);
}

.course-card__desc {
    font-size: 0.875rem;
    color: var(--text-secondary);
    line-height: 1.5;
    flex: 1;
    margin-bottom: var(--space-md);
}

.course-card__stats {
    display: flex;
    gap: var(--space-md);
    font-size: 0.8rem;
    color: var(--text-muted);
    margin-bottom: var(--space-md);
    padding-top: var(--space-sm);
    border-top: 1px solid var(--border-color);
}

.course-card__stat {
    display: flex;
    align-items: center;
    gap: 4px;
}

.course-card__cta {
    display: block;
    text-align: center;
    padding: var(--space-sm) var(--space-md);
    background: var(--accent-edu);
    color: white;
    text-decoration: none;
    border-radius: var(--radius-md);
    font-weight: 600;
    font-size: 0.875rem;
    transition: all var(--transition-fast);
}

.course-card:hover .course-card__cta {
    background: var(--accent-edu-hover);
}

/* Courses grid */
.courses-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: var(--space-lg);
}

/* ── Course status overlay ── */
.course-card__overlay {
    position: absolute;
    inset: 0;
    background: rgba(0, 0, 0, 0.55);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    border-radius: var(--radius-md) var(--radius-md) 0 0;
}
.course-card__overlay--pending {
    background: rgba(0, 0, 0, 0.35);
}
.course-card__lock { font-size: 2rem; }
.course-card__unlock-date {
    font-size: 0.75rem;
    font-weight: 700;
    color: #fff;
    background: rgba(255,255,255,0.15);
    padding: 0.2rem 0.6rem;
    border-radius: var(--radius-full);
    backdrop-filter: blur(4px);
}
.course-card__pending-badge {
    font-size: 0.7rem;
    font-weight: 700;
    color: #fff;
    background: rgba(255,165,0,0.7);
    padding: 0.25rem 0.75rem;
    border-radius: var(--radius-full);
}

/* ── Status row inside card content ── */
.course-card__status-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: var(--space-sm);
}
.course-status-badge {
    font-size: 0.65rem;
    font-weight: 700;
    padding: 0.2rem 0.5rem;
    border-radius: var(--radius-full);
    text-transform: uppercase;
    letter-spacing: 0.04em;
}
.course-status-badge--live   { background: #dcfce7; color: #15803d; }
.course-status-badge--pending { background: #fef9c3; color: #a16207; }
.course-status-badge--soon   { background: #f1f5f9; color: #64748b; }

/* ── CTA variants ── */
.course-card__cta--locked {
    background: var(--text-muted);
    cursor: default;
    opacity: 0.6;
}
.course-card__cta--pending {
    background: transparent;
    border: 1.5px solid var(--accent-edu);
    color: var(--accent-edu);
}
.course-card--soon {
    opacity: 0.75;
    pointer-events: none;
}
.course-card--soon:hover {
    transform: none;
    box-shadow: none;
}

/* ── Curriculum stats header ── */
.curriculum-stats {
    display: flex;
    gap: var(--space-lg);
    justify-content: center;
    margin: var(--space-lg) 0 var(--space-sm);
    flex-wrap: wrap;
}
.curriculum-stat {
    text-align: center;
    padding: var(--space-md) var(--space-xl);
    border-radius: var(--radius-lg);
    min-width: 140px;
}
.curriculum-stat--live    { background: #dcfce7; }
.curriculum-stat--pending { background: #fef9c3; }
.curriculum-stat--soon    { background: #f1f5f9; }
.curriculum-stat__num {
    display: block;
    font-size: 2rem;
    font-weight: 800;
    line-height: 1;
}
.curriculum-stat--live    .curriculum-stat__num { color: #15803d; }
.curriculum-stat--pending .curriculum-stat__num { color: #a16207; }
.curriculum-stat--soon    .curriculum-stat__num { color: #64748b; }
.curriculum-stat__label {
    font-size: 0.75rem;
    font-weight: 600;
    margin-top: 0.25rem;
    display: block;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

/* ── Curriculum progress bar ── */
.curriculum-progress-bar {
    height: 8px;
    background: var(--border-color);
    border-radius: var(--radius-full);
    overflow: hidden;
    margin: var(--space-md) auto;
    max-width: 600px;
}
.curriculum-progress-bar__fill {
    height: 100%;
    background: linear-gradient(90deg, #22c55e, #16a34a);
    border-radius: var(--radius-full);
    transition: width 0.6s ease;
}
.curriculum-progress-label {
    text-align: center;
    font-size: 0.8rem;
    color: var(--text-muted);
    margin-bottom: var(--space-lg);
}

/* ── Filter tabs ── */
.curriculum-tabs {
    display: flex;
    gap: var(--space-sm);
    margin-bottom: var(--space-lg);
    flex-wrap: wrap;
}
.curriculum-tab {
    padding: 0.4rem 1rem;
    border: 1.5px solid var(--border-color);
    background: transparent;
    border-radius: var(--radius-full);
    font-size: 0.85rem;
    font-weight: 600;
    cursor: pointer;
    color: var(--text-secondary);
    transition: all var(--transition-fast);
}
.curriculum-tab:hover { border-color: var(--accent-edu); color: var(--accent-edu); }
.curriculum-tab--active { background: var(--accent-edu); border-color: var(--accent-edu); color: white; }

/* ── Course pending / coming-soon banners on single page ── */
.course-coming-soon-banner,
.course-pending-banner {
    display: flex;
    gap: var(--space-md);
    align-items: flex-start;
    padding: var(--space-lg);
    border-radius: var(--radius-lg);
    margin-bottom: var(--space-xl);
}
.course-coming-soon-banner {
    background: #f1f5f9;
    border-left: 4px solid #64748b;
}
.course-pending-banner {
    background: #fefce8;
    border-left: 4px solid #ca8a04;
}
.course-coming-soon-banner__icon,
.course-pending-banner__icon {
    font-size: 1.75rem;
    flex-shrink: 0;
}
.course-coming-soon-banner p,
.course-pending-banner p {
    margin: 0.25rem 0 0;
    font-size: 0.9rem;
    color: var(--text-secondary);
}

/* Full-width layout: escapes the main-container grid when homepage or courses page is present */
.main-container:has(.homepage-full),
.main-container:has(.courses-page) {
    display: block;
}

.main-container:has(.homepage-full) > aside,
.main-container:has(.courses-page) > aside {
    display: none;
}

.homepage-full,
.courses-page {
    max-width: 100%;
}

/* Divider between content sections */
.section-divider {
    border: none;
    border-top: 1px solid var(--border-color);
    margin: var(--space-2xl) 0;
}

/* "Learn" nav item highlight */
.mega-nav__categories a.learn-link {
    color: var(--accent-edu);
}

.mega-nav__categories a.learn-link:hover {
    background: var(--accent-edu-light);
    color: var(--accent-edu-hover);
}

/* Courses index page */
.courses-page {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: var(--space-xl) var(--space-lg);
}

.courses-page__hero {
    text-align: center;
    padding: var(--space-2xl) var(--space-lg);
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: var(--radius-xl);
    color: white;
    margin-bottom: var(--space-2xl);
}

.courses-page__hero h1 {
    font-size: 2.5rem;
    margin-bottom: var(--space-md);
}

.courses-page__hero p {
    font-size: 1.1rem;
    opacity: 0.9;
    max-width: 560px;
    margin: 0 auto;
}

@media (max-width: 768px) {
    .courses-grid {
        grid-template-columns: 1fr;
    }

    .courses-page__hero h1 {
        font-size: 1.75rem;
    }

    .homepage-full {
        padding: var(--space-md);
    }
}

/* --- Print Styles --- */
@media print {
    .mega-nav,
    .sidebar,
    .comments-container,
    .site-footer,
    .reading-progress {
        display: none !important;
    }

    .page-wrapper {
        margin-top: 0;
    }

    .main-container {
        display: block;
    }
}