/* ========================================
   IDEAS BLOG - PROFESSIONAL PUBLICATION DESIGN
   Enhanced typography, reading UX, and visual polish
   ======================================== */

/* ===== GOOGLE FONTS ===== */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800;900&family=Merriweather:ital,wght@0,400;0,700;0,900;1,400;1,700&family=JetBrains+Mono:wght@400;500&display=swap');

/* ===== CSS VARIABLES ===== */
:root {
    /* Colors - Light Mode */
    --bg-primary: #ffffff;
    --bg-secondary: #f8fafc;
    --bg-tertiary: #f1f5f9;
    --bg-card: #ffffff;
    --text-primary: #0f172a;
    --text-secondary: #475569;
    --text-tertiary: #94a3b8;
    --text-muted: #64748b;

    /* Brand Colors */
    --primary: #3b82f6;
    --primary-light: #60a5fa;
    --primary-dark: #2563eb;
    --primary-gradient: linear-gradient(135deg, #3b82f6 0%, #8b5cf6 100%);
    --primary-gradient-hover: linear-gradient(135deg, #2563eb 0%, #7c3aed 100%);

    /* Accent Colors */
    --accent-green: #10b981;
    --accent-green-bg: rgba(16, 185, 129, 0.08);
    --accent-purple: #8b5cf6;
    --accent-purple-bg: rgba(139, 92, 246, 0.08);
    --accent-orange: #f59e0b;
    --accent-orange-bg: rgba(245, 158, 11, 0.08);
    --accent-red: #ef4444;
    --accent-red-bg: rgba(239, 68, 68, 0.08);
    --accent-blue: #0ea5e9;
    --accent-blue-bg: rgba(14, 165, 233, 0.08);

    /* Borders */
    --border-light: #e2e8f0;
    --border-medium: #cbd5e1;

    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
    --shadow-2xl: 0 25px 50px -12px rgb(0 0 0 / 0.25);

    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-2xl: 4rem;

    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-2xl: 1.5rem;
    --radius-full: 9999px;

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 300ms ease;
    --transition-slow: 500ms ease;

    /* Typography */
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'SF Pro Display', 'Segoe UI', Roboto, sans-serif;
    --font-serif: 'Merriweather', Georgia, 'Times New Roman', serif;
    --font-mono: 'JetBrains Mono', 'SF Mono', 'Fira Code', 'Cascadia Code', Monaco, monospace;
}

/* Dark Mode */
@media (prefers-color-scheme: dark) {
    :root {
        --bg-primary: #0f172a;
        --bg-secondary: #1e293b;
        --bg-tertiary: #334155;
        --bg-card: #1e293b;
        --text-primary: #f1f5f9;
        --text-secondary: #cbd5e1;
        --text-tertiary: #94a3b8;
        --text-muted: #64748b;

        --border-light: #334155;
        --border-medium: #475569;

        --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.3);
        --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.3), 0 2px 4px -2px rgb(0 0 0 / 0.3);
        --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.3), 0 4px 6px -4px rgb(0 0 0 / 0.3);
        --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.4);

        --accent-green-bg: rgba(16, 185, 129, 0.15);
        --accent-purple-bg: rgba(139, 92, 246, 0.15);
        --accent-orange-bg: rgba(245, 158, 11, 0.15);
        --accent-red-bg: rgba(239, 68, 68, 0.15);
        --accent-blue-bg: rgba(14, 165, 233, 0.15);
    }
}

/* ===== BASE STYLES ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    text-rendering: optimizeLegibility;
}

body {
    font-family: var(--font-sans);
    line-height: 1.7;
    color: var(--text-primary);
    background: var(--bg-primary);
    font-size: 16px;
    overflow-x: hidden;
}

/* ===== READING PROGRESS BAR ===== */
.reading-progress {
    position: fixed;
    top: 0;
    left: 0;
    width: 0%;
    height: 3px;
    background: var(--primary-gradient);
    z-index: 9999;
    transition: width 50ms linear;
    box-shadow: 0 0 10px rgba(59, 130, 246, 0.5);
}

.reading-progress::after {
    content: '';
    position: absolute;
    right: 0;
    top: 0;
    width: 60px;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.4));
    animation: shimmer 1.5s infinite;
}

@keyframes shimmer {
    0% { opacity: 0; }
    50% { opacity: 1; }
    100% { opacity: 0; }
}

/* ===== CONTAINER ===== */
.container {
    max-width: 900px;
    margin: 0 auto;
    padding: 80px 24px;
}

.container-article {
    max-width: 780px;
    margin: 0 auto;
    padding: 60px 24px;
}

/* ===== BREADCRUMB NAVIGATION ===== */
.breadcrumb {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 24px;
    font-size: 0.875rem;
    color: var(--text-muted);
    flex-wrap: wrap;
}

.breadcrumb a {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    transition: color var(--transition-fast);
}

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

.breadcrumb span {
    color: var(--text-muted);
}

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

/* ===== HEADER ===== */
header {
    margin-bottom: 64px;
    padding-bottom: 32px;
    border-bottom: 1px solid var(--border-light);
}

header h1 {
    font-size: 3rem;
    font-weight: 900;
    margin-bottom: 12px;
    letter-spacing: -0.04em;
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    line-height: 1.1;
}

header .description {
    font-size: 1.125rem;
    color: var(--text-secondary);
    line-height: 1.6;
    max-width: 600px;
}

header .category {
    display: inline-block;
    background: var(--primary);
    color: white;
    padding: 4px 12px;
    border-radius: var(--radius-full);
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    margin-bottom: 16px;
}

/* ===== NAVIGATION ===== */
nav {
    margin-top: 20px;
    display: flex;
    align-items: center;
    gap: 24px;
}

nav a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.9375rem;
    font-weight: 500;
    transition: color var(--transition-fast);
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

nav a:hover {
    color: var(--primary);
}

nav a::before {
    font-size: 0.875rem;
}

/* ===== POSTS GRID ===== */
.posts {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
    gap: 28px;
}

/* ===== POST CARD ===== */
.post {
    background: var(--bg-card);
    border-radius: var(--radius-xl);
    padding: 28px;
    border: 1px solid var(--border-light);
    transition: all var(--transition-base);
    position: relative;
    overflow: hidden;
    display: flex;
    flex-direction: column;
}

.post::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 3px;
    background: var(--primary-gradient);
    transform: scaleX(0);
    transform-origin: left;
    transition: transform var(--transition-base);
}

.post:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-xl);
    border-color: var(--primary-light);
}

.post:hover::before {
    transform: scaleX(1);
}

.post-meta {
    font-size: 0.8125rem;
    color: var(--text-muted);
    margin-bottom: 12px;
    font-weight: 500;
    display: flex;
    align-items: center;
    gap: 12px;
    flex-wrap: wrap;
}

.post-meta .read-time {
    display: inline-flex;
    align-items: center;
    gap: 4px;
}

.post-meta .read-time::before {
    content: '⏱';
    font-size: 0.75rem;
}

.post h2 {
    font-size: 1.375rem;
    font-weight: 700;
    margin-bottom: 12px;
    letter-spacing: -0.02em;
    line-height: 1.3;
}

.post h2 a {
    color: var(--text-primary);
    text-decoration: none;
    transition: color var(--transition-fast);
}

.post h2 a:hover {
    color: var(--primary);
}

.post-summary {
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: 16px;
    font-size: 0.9375rem;
    flex-grow: 1;
}

.post-tags {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
    margin-top: auto;
}

.tag {
    font-size: 0.6875rem;
    background: var(--bg-tertiary);
    color: var(--text-secondary);
    padding: 4px 10px;
    border-radius: var(--radius-full);
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    transition: all var(--transition-fast);
    border: 1px solid var(--border-light);
}

.tag:hover {
    background: var(--primary);
    color: white;
    border-color: var(--primary);
    transform: scale(1.05);
}

/* ===== ARTICLE PAGE ===== */
.article {
    max-width: 780px;
    margin: 0 auto;
}

/* Article Hero Banner */
.article-hero {
    background: var(--primary-gradient);
    border-radius: var(--radius-2xl);
    padding: 48px;
    margin-bottom: 48px;
    position: relative;
    overflow: hidden;
}

.article-hero::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -20%;
    width: 400px;
    height: 400px;
    background: radial-gradient(circle, rgba(255,255,255,0.1) 0%, transparent 70%);
    border-radius: 50%;
}

.article-hero::after {
    content: '';
    position: absolute;
    bottom: -30%;
    left: -10%;
    width: 300px;
    height: 300px;
    background: radial-gradient(circle, rgba(255,255,255,0.08) 0%, transparent 70%);
    border-radius: 50%;
}

.article-hero .category {
    background: rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(10px);
    color: white;
    border: 1px solid rgba(255, 255, 255, 0.3);
}

.article-hero h1 {
    font-size: 2.25rem;
    font-weight: 900;
    color: white;
    margin-bottom: 16px;
    letter-spacing: -0.03em;
    line-height: 1.15;
    position: relative;
    z-index: 1;
}

.article-hero .description {
    font-size: 1.0625rem;
    color: rgba(255, 255, 255, 0.9);
    line-height: 1.6;
    max-width: 600px;
    position: relative;
    z-index: 1;
}

.article-hero .post-meta {
    color: rgba(255, 255, 255, 0.8);
    position: relative;
    z-index: 1;
    margin-top: 20px;
}

.article-hero .post-meta::before {
    display: none;
}

.home-link {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 32px;
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    transition: all var(--transition-fast);
    font-size: 0.9375rem;
}

.home-link:hover {
    color: var(--primary);
    transform: translateX(-4px);
}

.article-header {
    margin-bottom: 48px;
}

.article-header h1 {
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: 16px;
    letter-spacing: -0.03em;
    line-height: 1.2;
}

.article-meta {
    font-size: 0.9375rem;
    color: var(--text-muted);
    font-weight: 500;
    display: flex;
    align-items: center;
    gap: 16px;
    flex-wrap: wrap;
}

.article-meta span {
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

/* ===== ARTICLE CONTENT ===== */
.article-content {
    line-height: 1.85;
    font-size: 1.0625rem;
    color: var(--text-secondary);
}

.article-content p {
    margin-bottom: 28px;
}

.article-content h2 {
    font-size: 1.875rem;
    margin-top: 64px;
    margin-bottom: 24px;
    font-weight: 800;
    letter-spacing: -0.025em;
    line-height: 1.3;
    color: var(--text-primary);
    position: relative;
    padding-bottom: 12px;
}

.article-content h2::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 48px;
    height: 3px;
    background: var(--primary-gradient);
    border-radius: var(--radius-full);
}

.article-content h3 {
    font-size: 1.375rem;
    margin-top: 48px;
    margin-bottom: 16px;
    font-weight: 700;
    letter-spacing: -0.015em;
    line-height: 1.4;
    color: var(--text-primary);
}

.article-content h4 {
    font-size: 1.125rem;
    margin-top: 32px;
    margin-bottom: 12px;
    font-weight: 600;
    color: var(--text-primary);
}

/* Section anchor links */
.heading-anchor {
    position: relative;
}

.heading-anchor a {
    position: absolute;
    left: -28px;
    top: 50%;
    transform: translateY(-50%);
    opacity: 0;
    color: var(--text-muted);
    text-decoration: none;
    font-size: 1.25rem;
    transition: opacity var(--transition-fast);
    padding: 4px;
}

.heading-anchor:hover a,
h2:hover .heading-anchor a,
h3:hover .heading-anchor a {
    opacity: 1;
}

/* ===== LISTS ===== */
.article-content ul,
.article-content ol {
    margin-bottom: 28px;
    padding-left: 28px;
}

.article-content li {
    margin-bottom: 10px;
    line-height: 1.75;
}

.article-content li::marker {
    color: var(--primary);
    font-weight: 600;
}

.article-content ul li {
    position: relative;
    padding-left: 8px;
}

.article-content ul li::before {
    content: '';
    position: absolute;
    left: -16px;
    top: 12px;
    width: 6px;
    height: 6px;
    background: var(--primary);
    border-radius: 50%;
}

/* ===== CALLOUT BOXES ===== */
.callout {
    border-radius: var(--radius-lg);
    padding: 20px 24px;
    margin-bottom: 32px;
    display: flex;
    gap: 16px;
    align-items: flex-start;
    border: 1px solid;
}

.callout-icon {
    font-size: 1.25rem;
    flex-shrink: 0;
    width: 28px;
    height: 28px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.callout-content {
    flex: 1;
}

.callout-content p:last-child {
    margin-bottom: 0;
}

.callout-title {
    font-weight: 700;
    font-size: 0.9375rem;
    margin-bottom: 6px;
    text-transform: uppercase;
    letter-spacing: 0.04em;
}

.callout-note {
    background: var(--accent-blue-bg);
    border-color: rgba(14, 165, 233, 0.25);
}

.callout-note .callout-icon { color: var(--accent-blue); }
.callout-note .callout-title { color: var(--accent-blue); }

.callout-tip {
    background: var(--accent-green-bg);
    border-color: rgba(16, 185, 129, 0.25);
}

.callout-tip .callout-icon { color: var(--accent-green); }
.callout-tip .callout-title { color: var(--accent-green); }

.callout-warning {
    background: var(--accent-orange-bg);
    border-color: rgba(245, 158, 11, 0.25);
}

.callout-warning .callout-icon { color: var(--accent-orange); }
.callout-warning .callout-title { color: var(--accent-orange); }

.callout-important {
    background: var(--accent-red-bg);
    border-color: rgba(239, 68, 68, 0.25);
}

.callout-important .callout-icon { color: var(--accent-red); }
.callout-important .callout-title { color: var(--accent-red); }

/* ===== CODE ===== */
.article-content code {
    background: var(--bg-tertiary);
    padding: 3px 8px;
    border-radius: var(--radius-sm);
    font-size: 0.875em;
    font-family: var(--font-mono);
    color: var(--accent-purple);
    border: 1px solid var(--border-light);
}

.article-content pre {
    background: var(--bg-tertiary);
    padding: 24px;
    border-radius: var(--radius-lg);
    overflow-x: auto;
    margin-bottom: 28px;
    border: 1px solid var(--border-light);
    position: relative;
}

.article-content pre code {
    background: none;
    padding: 0;
    border: none;
    font-size: 0.9375em;
    line-height: 1.6;
    color: var(--text-primary);
}

/* ===== TABLES ===== */
.article-content table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 32px;
    font-size: 0.9375em;
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-light);
}

.article-content table thead {
    background: var(--primary-gradient);
}

.article-content table th {
    padding: 14px 16px;
    text-align: left;
    font-weight: 700;
    color: white;
    font-size: 0.8125rem;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    white-space: nowrap;
}

.article-content table td {
    padding: 14px 16px;
    border-bottom: 1px solid var(--border-light);
    background: var(--bg-primary);
    color: var(--text-secondary);
    vertical-align: middle;
}

.article-content table tbody tr:nth-child(even) td {
    background: var(--bg-secondary);
}

.article-content table tbody tr:last-child td {
    border-bottom: none;
}

.article-content table tbody tr:hover td {
    background: var(--bg-tertiary);
}

/* Winner badge in tables */
.winner-badge {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    background: var(--accent-green-bg);
    color: var(--accent-green);
    padding: 3px 10px;
    border-radius: var(--radius-full);
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.04em;
}

.winner-badge::before {
    content: '🏆';
    font-size: 0.625rem;
}

/* Star ratings in tables */
.stars {
    color: var(--accent-orange);
    letter-spacing: 1px;
}

/* ===== COMPARISON TABLE ===== */
.comparison-table {
    margin-bottom: 40px;
}

.comparison-table > h2 {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 20px;
    color: var(--text-primary);
}

/* Side-by-side comparison card */
.comparison-cards {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    margin-bottom: 32px;
}

.comparison-card {
    background: var(--bg-card);
    border: 2px solid var(--border-light);
    border-radius: var(--radius-xl);
    padding: 28px;
    position: relative;
    transition: all var(--transition-base);
}

.comparison-card.winner {
    border-color: var(--accent-green);
    box-shadow: 0 0 0 4px rgba(16, 185, 129, 0.1);
}

.comparison-card.winner::before {
    content: 'Best Choice';
    position: absolute;
    top: -12px;
    left: 24px;
    background: var(--accent-green);
    color: white;
    padding: 2px 12px;
    border-radius: var(--radius-full);
    font-size: 0.6875rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.06em;
}

.comparison-card h3 {
    font-size: 1.25rem;
    font-weight: 800;
    margin-bottom: 8px;
    color: var(--text-primary);
}

.comparison-card .rating {
    color: var(--accent-orange);
    font-size: 0.875rem;
    font-weight: 600;
    margin-bottom: 16px;
}

.comparison-card .price {
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--primary);
    margin-bottom: 4px;
}

.comparison-card .price-note {
    font-size: 0.8125rem;
    color: var(--text-muted);
    margin-bottom: 16px;
}

.comparison-card ul {
    list-style: none;
    padding: 0;
    margin-bottom: 20px;
}

.comparison-card li {
    padding: 6px 0;
    border-bottom: 1px solid var(--border-light);
    font-size: 0.9375rem;
    color: var(--text-secondary);
    display: flex;
    align-items: center;
    gap: 8px;
}

.comparison-card li:last-child {
    border-bottom: none;
}

.comparison-card li::before {
    content: '✓';
    color: var(--accent-green);
    font-weight: 700;
}

/* ===== LINKS ===== */
.article-content a {
    color: var(--primary);
    text-decoration: none;
    font-weight: 500;
    transition: all var(--transition-fast);
    border-bottom: 2px solid transparent;
}

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

/* ===== BLOCKQUOTES ===== */
.article-content blockquote {
    border-left: 4px solid var(--primary);
    padding: 24px 28px;
    margin: 36px 0;
    background: var(--bg-secondary);
    border-radius: 0 var(--radius-lg) var(--radius-lg) 0;
    font-style: italic;
    color: var(--text-primary);
    font-size: 1.125rem;
    line-height: 1.75;
    font-family: var(--font-serif);
    position: relative;
}

.article-content blockquote::before {
    content: '"';
    position: absolute;
    top: -8px;
    left: 20px;
    font-size: 4rem;
    color: var(--primary);
    opacity: 0.2;
    font-family: var(--font-serif);
    line-height: 1;
}

.article-content blockquote p {
    margin-bottom: 0;
}

/* ===== HORIZONTAL RULE ===== */
.article-content hr {
    border: none;
    height: 2px;
    background: linear-gradient(90deg, var(--border-light), var(--primary-light), var(--border-light));
    margin: 56px 0;
}

/* ===== AFFILIATE DISCLOSURE ===== */
.affiliate-disclosure,
.disclosure-box {
    background: var(--accent-green-bg);
    border: 1px solid rgba(16, 185, 129, 0.2);
    border-radius: var(--radius-lg);
    padding: 20px 24px;
    margin-bottom: 40px;
    font-size: 0.9375rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

.affiliate-disclosure strong,
.disclosure-box strong {
    color: var(--accent-green);
    font-weight: 600;
}

/* ===== QUICK RECOMMENDATION CARDS ===== */
.quick-recommendation {
    margin-bottom: 48px;
}

.quick-recommendation h2 {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 24px;
    color: var(--text-primary);
}

.recommendation-card {
    background: var(--bg-secondary);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    padding: 24px;
    margin-bottom: 16px;
    transition: all var(--transition-base);
    position: relative;
    overflow: hidden;
}

.recommendation-card::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    height: 100%;
    width: 4px;
    background: var(--primary-gradient);
}

.recommendation-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-light);
}

.recommendation-card h3 {
    font-size: 1.125rem;
    font-weight: 700;
    margin-bottom: 8px;
    color: var(--primary);
}

.recommendation-card p {
    margin-bottom: 16px;
    color: var(--text-secondary);
}

/* ===== CTA BUTTON ===== */
.cta-button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    background: var(--primary-gradient);
    color: white;
    padding: 12px 28px;
    border-radius: var(--radius-md);
    text-decoration: none;
    font-weight: 600;
    font-size: 0.9375rem;
    transition: all var(--transition-base);
    box-shadow: var(--shadow-md);
    border: none;
    cursor: pointer;
}

.cta-button:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-xl);
    text-decoration: none;
    color: white;
    background: var(--primary-gradient-hover);
}

.cta-button::after {
    content: '→';
    transition: transform var(--transition-fast);
}

.cta-button:hover::after {
    transform: translateX(4px);
}

.cta-button-secondary {
    background: transparent;
    color: var(--primary);
    border: 2px solid var(--primary);
    box-shadow: none;
}

.cta-button-secondary:hover {
    background: var(--primary);
    color: white;
}

/* ===== BOOK/COURSE REVIEWS ===== */
.book-review,
.course-review {
    background: var(--bg-secondary);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-xl);
    padding: 32px;
    margin-bottom: 32px;
    position: relative;
}

.book-review h3,
.course-review h3 {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 16px;
    color: var(--text-primary);
}

.book-review p,
.course-review p {
    margin-bottom: 16px;
    color: var(--text-secondary);
}

.book-review h4,
.course-review h4 {
    font-size: 1.125rem;
    font-weight: 600;
    margin-top: 24px;
    margin-bottom: 12px;
    color: var(--text-primary);
}

.book-review ul,
.course-review ul {
    margin-bottom: 16px;
}

.book-review li,
.course-review li {
    margin-bottom: 8px;
}

.book-review li strong::before {
    content: '✓ ';
    color: var(--accent-green);
    font-weight: bold;
}

.book-review li strong.no::before {
    content: '✗ ';
    color: var(--accent-red);
}

/* ===== HOW TO CHOOSE ===== */
.how-to-choose {
    margin-bottom: 48px;
}

.how-to-choose h2 {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 20px;
    color: var(--text-primary);
}

.reader-level {
    background: var(--bg-secondary);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    padding: 24px;
    margin-bottom: 20px;
}

.reader-level h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--text-primary);
}

.reader-level ol {
    margin-bottom: 0;
}

/* ===== FAQ ===== */
.faq {
    margin-bottom: 48px;
}

.faq h2 {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 24px;
    color: var(--text-primary);
}

.faq-item {
    background: var(--bg-secondary);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    padding: 20px 24px;
    margin-bottom: 12px;
    transition: all var(--transition-base);
}

.faq-item:hover {
    border-color: var(--primary-light);
}

.faq-item h3 {
    font-size: 1.0625rem;
    font-weight: 600;
    margin-bottom: 8px;
    color: var(--text-primary);
}

.faq-item p {
    margin-bottom: 0;
    color: var(--text-secondary);
}

/* ===== AUTHOR BIO BOX ===== */
.author-bio {
    background: var(--bg-secondary);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-xl);
    padding: 28px 32px;
    margin-top: 64px;
    margin-bottom: 40px;
    display: flex;
    gap: 24px;
    align-items: flex-start;
}

.author-avatar {
    width: 72px;
    height: 72px;
    border-radius: 50%;
    background: var(--primary-gradient);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.75rem;
    font-weight: 800;
    color: white;
    flex-shrink: 0;
}

.author-info h3 {
    font-size: 1.125rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 4px;
}

.author-info .author-title {
    font-size: 0.875rem;
    color: var(--text-muted);
    margin-bottom: 12px;
}

.author-info p {
    font-size: 0.9375rem;
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 0;
}

/* ===== RELATED POSTS ===== */
.related-posts {
    margin-top: 64px;
    padding-top: 48px;
    border-top: 2px solid var(--border-light);
}

.related-posts h2 {
    font-size: 1.5rem;
    font-weight: 800;
    margin-bottom: 28px;
    color: var(--text-primary);
    letter-spacing: -0.02em;
}

.related-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
    gap: 20px;
}

.related-card {
    background: var(--bg-secondary);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    padding: 20px;
    transition: all var(--transition-base);
    text-decoration: none;
    display: block;
}

.related-card:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-light);
}

.related-card h3 {
    font-size: 0.9375rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 8px;
    line-height: 1.4;
}

.related-card:hover h3 {
    color: var(--primary);
}

.related-card p {
    font-size: 0.8125rem;
    color: var(--text-muted);
    margin-bottom: 0;
}

/* ===== SOCIAL SHARE ===== */
.share-section {
    margin-top: 48px;
    padding: 28px 0;
    border-top: 1px solid var(--border-light);
    border-bottom: 1px solid var(--border-light);
}

.share-section h3 {
    font-size: 0.9375rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 16px;
    text-transform: uppercase;
    letter-spacing: 0.06em;
}

.share-buttons {
    display: flex;
    gap: 12px;
    flex-wrap: wrap;
}

.share-btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 20px;
    border-radius: var(--radius-md);
    font-size: 0.875rem;
    font-weight: 600;
    text-decoration: none;
    transition: all var(--transition-fast);
    border: none;
    cursor: pointer;
}

.share-btn:hover {
    transform: translateY(-2px);
    text-decoration: none;
}

.share-btn-twitter {
    background: #1da1f2;
    color: white;
}

.share-btn-twitter:hover {
    background: #0c8de4;
    color: white;
}

.share-btn-linkedin {
    background: #0077b5;
    color: white;
}

.share-btn-linkedin:hover {
    background: #006399;
    color: white;
}

.share-btn-copy {
    background: var(--bg-tertiary);
    color: var(--text-secondary);
    border: 1px solid var(--border-medium);
}

.share-btn-copy:hover {
    background: var(--bg-secondary);
    color: var(--text-primary);
}

/* ===== TABLE OF CONTENTS (Floating) ===== */
.toc-container {
    position: fixed;
    top: 100px;
    right: 24px;
    width: 240px;
    max-height: calc(100vh - 120px);
    overflow-y: auto;
    background: var(--bg-secondary);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-xl);
    padding: 20px;
    z-index: 100;
    opacity: 0;
    transform: translateX(20px);
    transition: all var(--transition-base);
    pointer-events: none;
}

.toc-container.visible {
    opacity: 1;
    transform: translateX(0);
    pointer-events: auto;
}

.toc-container h4 {
    font-size: 0.75rem;
    font-weight: 700;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    margin-bottom: 12px;
}

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

.toc-list li {
    margin-bottom: 8px;
}

.toc-list a {
    font-size: 0.8125rem;
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    display: block;
    padding: 4px 0;
    border-left: 2px solid transparent;
    padding-left: 12px;
    transition: all var(--transition-fast);
}

.toc-list a:hover,
.toc-list a.active {
    color: var(--primary);
    border-left-color: var(--primary);
}

.toc-list a.active {
    font-weight: 700;
}

/* ===== ARCHIVE ===== */
.archive-section {
    margin-bottom: 48px;
}

.archive-section h2 {
    font-size: 0.8125rem;
    font-weight: 700;
    margin-bottom: 24px;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.08em;
}

.archive-list {
    list-style: none;
}

.archive-item {
    margin-bottom: 12px;
}

.archive-item a {
    color: var(--text-primary);
    text-decoration: none;
    font-size: 1rem;
    font-weight: 500;
    transition: color var(--transition-fast);
}

.archive-item a:hover {
    color: var(--primary);
}

.archive-date {
    color: var(--text-muted);
    font-size: 0.875rem;
    margin-left: 12px;
    font-weight: 400;
}

/* ===== FOOTER ===== */
footer {
    margin-top: 80px;
    padding-top: 32px;
    padding-bottom: 48px;
    border-top: 1px solid var(--border-light);
    text-align: center;
}

footer p {
    color: var(--text-muted);
    font-size: 0.875rem;
    margin-bottom: 8px;
}

footer a {
    color: var(--text-secondary);
    text-decoration: none;
    transition: color var(--transition-fast);
}

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

/* ===== RESPONSIVE DESIGN ===== */
@media (max-width: 1200px) {
    .toc-container {
        display: none;
    }
}

@media (max-width: 768px) {
    .container {
        padding: 48px 20px;
    }

    .container-article {
        padding: 40px 20px;
    }

    header h1 {
        font-size: 2.25rem;
    }

    header .description {
        font-size: 1rem;
    }

    .posts {
        grid-template-columns: 1fr;
        gap: 20px;
    }

    .post {
        padding: 24px;
    }

    .post h2 {
        font-size: 1.25rem;
    }

    .article-hero {
        padding: 32px 24px;
        border-radius: var(--radius-xl);
    }

    .article-hero h1 {
        font-size: 1.75rem;
    }

    .article-header h1 {
        font-size: 2rem;
    }

    .article-content {
        font-size: 1rem;
    }

    .article-content h2 {
        font-size: 1.5rem;
    }

    .article-content h3 {
        font-size: 1.25rem;
    }

    .article-content table {
        font-size: 0.8125em;
    }

    .comparison-cards {
        grid-template-columns: 1fr;
    }

    .book-review,
    .course-review {
        padding: 24px;
    }

    nav {
        flex-wrap: wrap;
        gap: 16px;
    }

    .author-bio {
        flex-direction: column;
        align-items: center;
        text-align: center;
    }

    .share-buttons {
        justify-content: center;
    }

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

@media (max-width: 640px) {
    body {
        font-size: 15px;
    }

    header {
        margin-bottom: 40px;
    }

    header h1 {
        font-size: 1.75rem;
    }

    .container {
        padding: 32px 16px;
    }

    .post {
        padding: 20px;
    }

    .article-content blockquote {
        font-size: 1rem;
        padding: 20px;
    }

    .recommendation-card {
        padding: 20px;
    }

    .affiliate-disclosure,
    .disclosure-box {
        padding: 16px 20px;
    }
}

/* ===== UTILITY CLASSES ===== */
.text-gradient {
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.badge {
    display: inline-block;
    padding: 4px 12px;
    border-radius: var(--radius-full);
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.badge-primary {
    background: var(--primary);
    color: white;
}

.badge-success {
    background: var(--accent-green);
    color: white;
}

.badge-purple {
    background: var(--accent-purple);
    color: white;
}

.text-center { text-align: center; }
.text-right { text-align: right; }

.mt-sm { margin-top: var(--spacing-sm); }
.mt-md { margin-top: var(--spacing-md); }
.mt-lg { margin-top: var(--spacing-lg); }
.mt-xl { margin-top: var(--spacing-xl); }

.mb-sm { margin-bottom: var(--spacing-sm); }
.mb-md { margin-bottom: var(--spacing-md); }
.mb-lg { margin-bottom: var(--spacing-lg); }
.mb-xl { margin-bottom: var(--spacing-xl); }

/* ===== ANIMATIONS ===== */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes slideInRight {
    from {
        opacity: 0;
        transform: translateX(20px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

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

.post,
.article-content section {
    animation: fadeIn var(--transition-slow) ease-out;
}

.article-hero {
    animation: fadeIn 0.6s ease-out;
}

/* ===== SCROLLBAR ===== */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

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

::-webkit-scrollbar-thumb {
    background: var(--border-medium);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--text-muted);
}

/* ===== SELECTION ===== */
::selection {
    background: var(--primary);
    color: white;
}

::-moz-selection {
    background: var(--primary);
    color: white;
}

/* ===== FOCUS ===== */
:focus-visible {
    outline: 2px solid var(--primary);
    outline-offset: 2px;
}

/* ===== PRINT ===== */
@media print {
    .post,
    .recommendation-card,
    .book-review,
    .course-review,
    .faq-item,
    .share-section,
    .related-posts,
    .toc-container,
    .reading-progress,
    .article-hero::before,
    .article-hero::after {
        break-inside: avoid;
    }

    .article-hero {
        background: none;
        border: 2px solid #333;
    }

    .article-hero h1 {
        color: #000;
        -webkit-text-fill-color: #000;
    }

    .article-hero .description,
    .article-hero .post-meta {
        color: #333;
    }

    .article-hero .category {
        background: #333;
    }

    .article-content h2::after {
        display: none;
    }
}