/* ==================== 基础样式 ==================== */
:root {
    --primary-color: #1a5f4a;
    --primary-dark: #0d3d2e;
    --primary-light: #2d8f6f;
    --secondary-color: #c9a227;
    --secondary-dark: #9a7b1c;
    --accent-color: #e85d04;
    --bg-light: #f8f9fa;
    --bg-dark: #1a1a2e;
    --text-primary: #2c3e50;
    --text-secondary: #6c757d;
    --text-light: #f8f9fa;
    --shadow-sm: 0 2px 8px rgba(0,0,0,0.08);
    --shadow-md: 0 4px 16px rgba(0,0,0,0.12);
    --shadow-lg: 0 8px 32px rgba(0,0,0,0.16);
    --border-radius: 12px;
    --transition: all 0.3s ease;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    color: var(--text-primary);
    line-height: 1.6;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
}

/* ==================== 深色主题 ==================== */
body.dark-theme {
    --bg-light: #1a1a2e;
    --text-primary: #f8f9fa;
    --text-secondary: #adb5bd;
}

body.dark-theme .section.bg-light {
    background: rgba(255,255,255,0.05);
}

body.dark-theme .concept-card,
body.dark-theme .framework-card,
body.dark-theme .quote-card {
    background: rgba(255,255,255,0.08);
}

body.dark-theme .timeline-content,
body.dark-theme .mistake-card {
    background: rgba(255,255,255,0.06);
}

/* ==================== 头部导航 ==================== */
.main-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255,255,255,0.95);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-sm);
    z-index: 1000;
    transition: var(--transition);
}

body.dark-theme .main-header {
    background: rgba(26,26,46,0.95);
}

.header-content {
    max-width: 1400px;
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.logo-icon {
    font-size: 1.75rem;
}

.logo-text {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--primary-color);
}

.main-nav {
    display: flex;
    gap: 0.5rem;
}

.nav-link {
    padding: 0.5rem 1.25rem;
    color: var(--text-primary);
    text-decoration: none;
    font-weight: 500;
    border-radius: 8px;
    transition: var(--transition);
}

.nav-link:hover,
.nav-link.active {
    background: var(--primary-color);
    color: white;
}

.theme-toggle {
    background: none;
    border: 2px solid var(--primary-color);
    border-radius: 50%;
    width: 40px;
    height: 40px;
    cursor: pointer;
    font-size: 1.25rem;
    transition: var(--transition);
}

.theme-toggle:hover {
    background: var(--primary-color);
    color: white;
}

/* ==================== 英雄区域 ==================== */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 6rem 2rem 4rem;
    position: relative;
    overflow: hidden;
    background: linear-gradient(135deg, rgba(102,126,234,0.9) 0%, rgba(118,75,162,0.9) 100%);
}

.hero-content {
    max-width: 700px;
    text-align: center;
    z-index: 2;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    color: white;
    margin-bottom: 1rem;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.2);
}

.hero-subtitle {
    font-size: 1.25rem;
    color: rgba(255,255,255,0.9);
    margin-bottom: 1.5rem;
}

.hero-description {
    font-size: 1.1rem;
    color: rgba(255,255,255,0.85);
    margin-bottom: 2rem;
    line-height: 1.8;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

.btn {
    padding: 0.875rem 2rem;
    border-radius: 50px;
    font-weight: 600;
    text-decoration: none;
    transition: var(--transition);
    cursor: pointer;
    border: none;
    font-size: 1rem;
}

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

.btn-primary:hover {
    background: var(--secondary-dark);
    transform: translateY(-2px);
    box-shadow: 0 4px 20px rgba(201,162,39,0.4);
}

.btn-secondary {
    background: rgba(255,255,255,0.2);
    color: white;
    border: 2px solid white;
}

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

.hero-visual {
    position: absolute;
    inset: 0;
    pointer-events: none;
    z-index: 1;
}

.floating-card {
    position: absolute;
    background: rgba(255,255,255,0.15);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255,255,255,0.2);
    border-radius: var(--border-radius);
    padding: 1rem 1.5rem;
    display: flex;
    align-items: center;
    gap: 0.75rem;
    color: white;
    font-weight: 600;
    animation: float 6s ease-in-out infinite;
}

.floating-card .card-icon {
    font-size: 1.5rem;
}

.card-1 { top: 20%; left: 10%; animation-delay: 0s; }
.card-2 { top: 30%; right: 15%; animation-delay: 1s; }
.card-3 { bottom: 25%; left: 15%; animation-delay: 2s; }
.card-4 { bottom: 30%; right: 10%; animation-delay: 3s; }

@keyframes float {
    0%, 100% { transform: translateY(0) rotate(0deg); }
    50% { transform: translateY(-20px) rotate(2deg); }
}

/* ==================== 通用区域样式 ==================== */
.section {
    padding: 5rem 2rem;
    max-width: 1400px;
    margin: 0 auto;
}

.section.bg-light {
    background: var(--bg-light);
    max-width: none;
}

.section.bg-light > * {
    max-width: 1400px;
    margin: 0 auto;
}

.section-header {
    text-align: center;
    margin-bottom: 3rem;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    color: white;
    margin-bottom: 0.5rem;
}

body.dark-theme .section-title {
    color: white;
}

.section-subtitle {
    font-size: 1.1rem;
    color: rgba(255,255,255,0.8);
}

body.dark-theme .section-subtitle {
    color: rgba(255,255,255,0.7);
}

/* ==================== 知识图谱 ==================== */
.graph-container {
    background: rgba(255,255,255,0.95);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-lg);
    overflow: hidden;
    position: relative;
    min-height: 600px;
}

body.dark-theme .graph-container {
    background: rgba(30,30,50,0.95);
}

.graph-controls {
    position: absolute;
    top: 1rem;
    left: 1rem;
    z-index: 10;
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.graph-btn {
    padding: 0.5rem 1rem;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-size: 0.875rem;
    transition: var(--transition);
}

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

.graph-filter {
    padding: 0.5rem;
    border: 1px solid #ddd;
    border-radius: 6px;
    background: white;
    cursor: pointer;
}

#graph-canvas {
    width: 100%;
    height: 600px;
}

.graph-legend {
    position: absolute;
    bottom: 1rem;
    left: 1rem;
    display: flex;
    gap: 1rem;
    background: rgba(255,255,255,0.9);
    padding: 0.75rem 1rem;
    border-radius: 8px;
    font-size: 0.875rem;
}

body.dark-theme .graph-legend {
    background: rgba(30,30,50,0.9);
}

.legend-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.legend-dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
}

.legend-dot.philosophy { background: #e74c3c; }
.legend-dot.valuation { background: #3498db; }
.legend-dot.business { background: #2ecc71; }
.legend-dot.capital { background: #f39c12; }

/* 节点详情面板 */
.node-detail-panel {
    position: absolute;
    top: 0;
    right: -400px;
    width: 380px;
    height: 100%;
    background: white;
    box-shadow: var(--shadow-lg);
    padding: 1.5rem;
    overflow-y: auto;
    transition: right 0.3s ease;
    z-index: 20;
}

body.dark-theme .node-detail-panel {
    background: var(--bg-dark);
}

.node-detail-panel.open {
    right: 0;
}

.close-panel {
    position: absolute;
    top: 1rem;
    right: 1rem;
    width: 32px;
    height: 32px;
    border: none;
    background: #eee;
    border-radius: 50%;
    cursor: pointer;
    font-size: 1.25rem;
    transition: var(--transition);
}

.close-panel:hover {
    background: #ddd;
}

/* ==================== 核心概念卡片 ==================== */
.concepts-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1.5rem;
}

.concept-card {
    background: rgba(255,255,255,0.95);
    border-radius: var(--border-radius);
    padding: 1.5rem;
    box-shadow: var(--shadow-sm);
    cursor: pointer;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

body.dark-theme .concept-card {
    background: rgba(255,255,255,0.08);
}

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

.concept-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
}

.concept-icon {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.concept-name {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.concept-brief {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin-bottom: 1rem;
    line-height: 1.5;
}

.concept-tags {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 1rem;
}

.tag {
    background: var(--primary-color);
    color: white;
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 500;
}

.concept-links {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
}

.link-item {
    color: var(--primary-color);
    font-size: 0.85rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
}

.link-item:hover {
    color: var(--secondary-color);
    text-decoration: underline;
}

/* ==================== 深度分析 ==================== */
.analysis-tabs {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 2rem;
}

.tab-btn {
    padding: 0.75rem 1.5rem;
    background: rgba(255,255,255,0.2);
    border: 2px solid rgba(255,255,255,0.3);
    color: white;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 600;
    transition: var(--transition);
}

.tab-btn:hover,
.tab-btn.active {
    background: white;
    color: var(--primary-color);
    border-color: white;
}

.analysis-content {
    display: block;
}

.analysis-content.hidden {
    display: none;
}

/* 时间线 */
.timeline {
    position: relative;
    padding-left: 2rem;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 4px;
    background: linear-gradient(to bottom, var(--primary-color), var(--secondary-color));
    border-radius: 2px;
}

.timeline-item {
    position: relative;
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    background: rgba(255,255,255,0.95);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-sm);
}

body.dark-theme .timeline-item {
    background: rgba(255,255,255,0.06);
}

.timeline-marker {
    position: absolute;
    left: -2.5rem;
    top: 1.5rem;
    background: var(--primary-color);
    color: white;
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 600;
}

.timeline-content h3 {
    color: var(--primary-color);
    margin-bottom: 0.75rem;
}

.timeline-content p {
    color: var(--text-secondary);
    margin-bottom: 1rem;
    line-height: 1.7;
}

.timeline-links,
.mistake-links {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
}

.timeline-links a,
.mistake-links a,
.quote-concepts .concept-tag {
    background: var(--primary-color);
    color: white;
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.8rem;
    text-decoration: none;
    cursor: pointer;
    transition: var(--transition);
}

.timeline-links a:hover,
.mistake-links a:hover {
    background: var(--secondary-color);
}

/* 分析框架网格 */
.framework-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 1.5rem;
}

.framework-card {
    background: rgba(255,255,255,0.95);
    border-radius: var(--border-radius);
    padding: 1.5rem;
    box-shadow: var(--shadow-sm);
}

body.dark-theme .framework-card {
    background: rgba(255,255,255,0.06);
}

.framework-card h3 {
    color: var(--primary-color);
    margin-bottom: 1rem;
    font-size: 1.1rem;
}

.framework-step {
    display: flex;
    gap: 1rem;
    margin-bottom: 1rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid #eee;
}

body.dark-theme .framework-step {
    border-color: rgba(255,255,255,0.1);
}

.framework-step:last-child {
    border-bottom: none;
    margin-bottom: 0;
    padding-bottom: 0;
}

.step-num {
    width: 32px;
    height: 32px;
    background: var(--secondary-color);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    flex-shrink: 0;
}

.step-content {
    flex: 1;
}

.step-content strong {
    display: block;
    margin-bottom: 0.25rem;
}

.step-content p {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.step-content a {
    display: inline-block;
    margin-top: 0.5rem;
    margin-right: 0.5rem;
    color: var(--primary-color);
    font-size: 0.85rem;
}

/* 护城河来源 */
.moat-sources {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.moat-source {
    display: flex;
    align-items: flex-start;
    gap: 0.75rem;
    padding: 0.75rem;
    background: rgba(26,95,74,0.05);
    border-radius: 8px;
}

body.dark-theme .moat-source {
    background: rgba(255,255,255,0.05);
}

.source-icon {
    font-size: 1.5rem;
}

.moat-source strong {
    display: block;
    margin-bottom: 0.25rem;
}

.moat-source p {
    font-size: 0.85rem;
    color: var(--text-secondary);
}

/* 管理层问题 */
.management-questions {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.question-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.75rem;
    background: rgba(201,162,39,0.1);
    border-radius: 8px;
}

body.dark-theme .question-item {
    background: rgba(255,255,255,0.05);
}

.q-icon {
    width: 28px;
    height: 28px;
    background: var(--secondary-color);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 0.85rem;
    flex-shrink: 0;
}

.question-item p {
    flex: 1;
    font-size: 0.9rem;
}

.question-item a {
    color: var(--primary-color);
    font-size: 0.85rem;
    margin-left: 0.5rem;
}

/* 常见误区 */
.mistakes-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 1.5rem;
}

.mistake-card {
    background: rgba(255,255,255,0.95);
    border-radius: var(--border-radius);
    padding: 1.5rem;
    box-shadow: var(--shadow-sm);
    border-left: 4px solid var(--accent-color);
}

body.dark-theme .mistake-card {
    background: rgba(255,255,255,0.06);
}

.mistake-icon {
    font-size: 1.5rem;
    margin-bottom: 0.75rem;
}

.mistake-card h3 {
    color: var(--accent-color);
    margin-bottom: 0.5rem;
    font-size: 1rem;
}

.mistake-card p {
    color: var(--text-secondary);
    font-size: 0.9rem;
    line-height: 1.6;
    margin-bottom: 1rem;
}

/* ==================== 语录区域 ==================== */
.quotes-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 1.5rem;
}

.quote-card {
    background: rgba(255,255,255,0.95);
    border-radius: var(--border-radius);
    padding: 1.5rem;
    box-shadow: var(--shadow-sm);
}

body.dark-theme .quote-card {
    background: rgba(255,255,255,0.06);
}

.quote-card.quote-buffett {
    border-top: 4px solid var(--primary-color);
}

.quote-card.quote-munger {
    border-top: 4px solid var(--secondary-color);
}

.quote-author {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1rem;
}

.author-avatar {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    object-fit: cover;
    border: 3px solid var(--primary-color);
}

.quote-munger .author-avatar {
    border-color: var(--secondary-color);
}

.author-info {
    display: flex;
    flex-direction: column;
}

.author-name {
    font-weight: 700;
    color: var(--text-primary);
}

.author-title {
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.quote-text {
    font-size: 1rem;
    font-style: italic;
    color: var(--text-primary);
    line-height: 1.7;
    margin-bottom: 1rem;
    padding: 1rem;
    background: rgba(26,95,74,0.05);
    border-radius: 8px;
    border-left: 3px solid var(--primary-color);
}

body.dark-theme .quote-text {
    background: rgba(255,255,255,0.05);
}

.quote-munger .quote-text {
    border-left-color: var(--secondary-color);
    background: rgba(201,162,39,0.05);
}

.quote-concepts {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.quote-concepts .concept-tag {
    background: var(--primary-color);
    color: white;
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.8rem;
    cursor: pointer;
    transition: var(--transition);
}

.quote-concepts .concept-tag:hover {
    background: var(--secondary-color);
}

/* ==================== 页脚 ==================== */
.main-footer {
    background: rgba(26,26,46,0.95);
    color: white;
    padding: 4rem 2rem 2rem;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h4 {
    font-size: 1.1rem;
    margin-bottom: 1rem;
    color: var(--secondary-color);
}

.footer-section p {
    color: rgba(255,255,255,0.7);
    line-height: 1.6;
}

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

.footer-section li {
    margin-bottom: 0.5rem;
}

.footer-section a {
    color: rgba(255,255,255,0.7);
    text-decoration: none;
    transition: var(--transition);
}

.footer-section a:hover {
    color: white;
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid rgba(255,255,255,0.1);
    color: rgba(255,255,255,0.5);
    font-size: 0.9rem;
}

/* ==================== 模态框 ==================== */
.concept-modal {
    position: fixed;
    inset: 0;
    z-index: 2000;
    display: none;
    align-items: center;
    justify-content: center;
}

.concept-modal.open {
    display: flex;
}

.modal-overlay {
    position: absolute;
    inset: 0;
    background: rgba(0,0,0,0.6);
}

.modal-content {
    position: relative;
    max-width: 800px;
    width: 90%;
    max-height: 85vh;
    background: white;
    border-radius: var(--border-radius);
    overflow-y: auto;
    padding: 2rem;
}

body.dark-theme .modal-content {
    background: var(--bg-dark);
}

.modal-close {
    position: absolute;
    top: 1rem;
    right: 1rem;
    width: 40px;
    height: 40px;
    border: none;
    background: #eee;
    border-radius: 50%;
    cursor: pointer;
    font-size: 1.5rem;
    transition: var(--transition);
}

.modal-close:hover {
    background: #ddd;
}

/* ==================== 响应式 ==================== */
@media (max-width: 768px) {
    .main-nav {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        padding: 1rem;
        box-shadow: var(--shadow-md);
    }
    
    body.dark-theme .main-nav {
        background: var(--bg-dark);
    }
    
    .main-nav.open {
        display: flex;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .floating-card {
        display: none;
    }
    
    .analysis-tabs {
        flex-direction: column;
    }
    
    .node-detail-panel {
        width: 100%;
        right: -100%;
    }
}

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

.concept-card,
.quote-card,
.framework-card,
.mistake-card,
.timeline-item {
    animation: fadeIn 0.5s ease forwards;
}

.concepts-grid .concept-card:nth-child(1) { animation-delay: 0.1s; }
.concepts-grid .concept-card:nth-child(2) { animation-delay: 0.2s; }
.concepts-grid .concept-card:nth-child(3) { animation-delay: 0.3s; }
.concepts-grid .concept-card:nth-child(4) { animation-delay: 0.4s; }
.concepts-grid .concept-card:nth-child(5) { animation-delay: 0.5s; }
.concepts-grid .concept-card:nth-child(6) { animation-delay: 0.6s; }
.concepts-grid .concept-card:nth-child(7) { animation-delay: 0.7s; }
.concepts-grid .concept-card:nth-child(8) { animation-delay: 0.8s; }

/* 节点样式 */
.node circle {
    stroke: #fff;
    stroke-width: 2px;
    cursor: pointer;
    transition: all 0.3s ease;
}

.node circle:hover {
    stroke-width: 4px;
    filter: brightness(1.2);
}

.node text {
    font-size: 11px;
    font-weight: 600;
    fill: #333;
    pointer-events: none;
}

body.dark-theme .node text {
    fill: #fff;
}

.link {
    stroke: #999;
    stroke-opacity: 0.6;
    fill: none;
}

/* ==================== 模态框内容样式 ==================== */
#concept-modal-body h2 {
    font-size: 1.75rem;
    color: var(--primary-color);
    margin-bottom: 1rem;
    padding-bottom: 0.75rem;
    border-bottom: 2px solid var(--secondary-color);
}

.detail-section {
    margin-bottom: 1.5rem;
}

.detail-section h3 {
    font-size: 1.1rem;
    color: var(--text-primary);
    margin-bottom: 0.75rem;
    font-weight: 600;
}

.detail-section p {
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: 0.5rem;
}

.detail-section ul,
.detail-section ol {
    margin-left: 1.5rem;
    color: var(--text-secondary);
}

.detail-section li {
    margin-bottom: 0.5rem;
    line-height: 1.6;
}

.detail-section blockquote {
    background: rgba(26,95,74,0.08);
    border-left: 4px solid var(--primary-color);
    padding: 1rem;
    margin: 1rem 0;
    font-style: italic;
    color: var(--text-primary);
    border-radius: 0 8px 8px 0;
}

.detail-section .formula {
    background: #f8f9fa;
    padding: 1rem;
    border-radius: 8px;
    font-family: 'Courier New', monospace;
    color: var(--primary-color);
    font-weight: 600;
}

body.dark-theme .detail-section .formula {
    background: rgba(255,255,255,0.1);
}

.related-concepts {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-top: 0.75rem;
}

.related-tag {
    background: var(--primary-color);
    color: white;
    padding: 0.35rem 0.85rem;
    border-radius: 20px;
    font-size: 0.85rem;
    cursor: pointer;
    transition: all 0.3s ease;
}

.related-tag:hover {
    background: var(--secondary-color);
    transform: translateY(-2px);
}

.category-badge {
    display: inline-block;
    padding: 0.35rem 0.85rem;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 600;
    color: white;
}

.category-badge.philosophy { background: #e74c3c; }
.category-badge.valuation { background: #3498db; }
.category-badge.business { background: #2ecc71; }
.category-badge.capital { background: #f39c12; }