/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #667eea;
    --secondary-color: #764ba2;
    --accent-color: #f093fb;
    --text-color: #333;
    --text-light: #666;
    --background-color: #f8f9fa;
    --white: #ffffff;
    --border-color: #e9ecef;
    --shadow: 0 2px 10px rgba(0,0,0,0.1);
    --shadow-hover: 0 4px 20px rgba(0,0,0,0.15);
    --border-radius: 12px;
    --transition: all 0.3s ease;
    --nav-width: 280px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background: var(--background-color);
    margin-left: var(--nav-width);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

/* Navigation */
.main-nav {
    position: fixed;
    top: 0;
    left: 0;
    width: var(--nav-width);
    height: 100vh;
    background: linear-gradient(180deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    z-index: 1000;
    overflow-y: auto;
    box-shadow: 4px 0 20px rgba(0,0,0,0.15);
    transition: var(--transition);
}

.nav-container {
    padding: 2rem 0;
}

.nav-header {
    padding: 0 1.5rem 2rem 1.5rem;
    border-bottom: 1px solid rgba(255,255,255,0.1);
    margin-bottom: 1rem;
}

.nav-title {
    color: var(--white);
    font-size: 1.2rem;
    font-weight: bold;
    margin: 0;
}

.nav-subtitle {
    color: rgba(255,255,255,0.8);
    font-size: 0.8rem;
    margin: 0.25rem 0 0 0;
}

.nav-links {
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
    list-style: none;
    padding: 0 1rem;
    margin: 0;
}

.nav-links li {
    width: 100%;
}

.nav-links a {
    color: rgba(255,255,255,0.9);
    text-decoration: none;
    font-weight: 500;
    font-size: 0.95rem;
    padding: 0.8rem 1rem;
    border-radius: 8px;
    transition: var(--transition);
    display: flex;
    align-items: center;
    position: relative;
    margin-bottom: 0.25rem;
}

.nav-links a:hover {
    background: rgba(255,255,255,0.15);
    color: var(--white);
    transform: translateX(5px);
    box-shadow: 0 2px 8px rgba(0,0,0,0.2);
}

.nav-links a.active {
    background: rgba(255,255,255,0.2);
    color: var(--white);
    border-left: 4px solid var(--white);
}

.nav-toggle {
    display: none;
    position: fixed;
    top: 1rem;
    left: 1rem;
    z-index: 1001;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: var(--white);
    border: none;
    width: 50px;
    height: 50px;
    border-radius: 8px;
    cursor: pointer;
    font-size: 1.2rem;
    box-shadow: var(--shadow);
}

/* Header */
.main-header {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: var(--white);
    padding: 4rem 0;
    text-align: center;
    box-shadow: var(--shadow);
}

.main-header h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
    font-weight: 700;
}

.main-header .subtitle {
    font-size: 1.3rem;
    opacity: 0.9;
    margin-bottom: 2rem;
}

.header-actions {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 0.8rem 2rem;
    border-radius: var(--border-radius);
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition);
    border: none;
    cursor: pointer;
    font-size: 1rem;
}

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

.btn-primary:hover {
    background: #f8f9fa;
    transform: translateY(-2px);
    box-shadow: var(--shadow-hover);
}

.btn-secondary {
    background: transparent;
    color: var(--white);
    border: 2px solid var(--white);
}

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

/* Main Content */
.main-content {
    padding: 3rem 0;
}

.content-section {
    background: var(--white);
    margin-bottom: 3rem;
    padding: 3rem;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
}

.content-section h2 {
    color: var(--primary-color);
    font-size: 2.2rem;
    margin-bottom: 2rem;
    border-bottom: 3px solid var(--primary-color);
    padding-bottom: 0.5rem;
}

/* Overview Grid */
.overview-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.overview-card {
    background: var(--white);
    padding: 2rem;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    transition: var(--transition);
    border: 1px solid var(--border-color);
}

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

.card-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.overview-card h3 {
    color: var(--secondary-color);
    font-size: 1.4rem;
    margin-bottom: 1rem;
}

.overview-card p {
    color: var(--text-light);
    margin-bottom: 1.5rem;
}

.card-link {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition);
}

.card-link:hover {
    color: var(--secondary-color);
}

/* Quick Start Steps */
.quick-start-steps {
    display: flex;
    flex-direction: column;
    gap: 2rem;
    margin-top: 2rem;
}

.step {
    display: flex;
    align-items: flex-start;
    gap: 1.5rem;
    padding: 1.5rem;
    background: #f8f9fa;
    border-radius: var(--border-radius);
    border-left: 4px solid var(--primary-color);
}

.step-number {
    background: var(--primary-color);
    color: var(--white);
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    font-size: 1.2rem;
    flex-shrink: 0;
}

.step-content h3 {
    color: var(--secondary-color);
    margin-bottom: 0.5rem;
}

.step-content p {
    color: var(--text-light);
}

/* Features Grid */
.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
}

.feature-item {
    padding: 1.5rem;
    background: #f8f9fa;
    border-radius: var(--border-radius);
    transition: var(--transition);
}

.feature-item:hover {
    background: var(--white);
    box-shadow: var(--shadow);
}

.feature-item h3 {
    color: var(--secondary-color);
    margin-bottom: 0.5rem;
    font-size: 1.1rem;
}

.feature-item p {
    color: var(--text-light);
    font-size: 0.9rem;
}

/* Documentation Links */
.doc-links {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
}

.doc-link {
    display: block;
    padding: 2rem;
    background: var(--white);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    text-decoration: none;
    transition: var(--transition);
    color: inherit;
}

.doc-link:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-hover);
    border-color: var(--primary-color);
}

.doc-link h3 {
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.doc-link p {
    color: var(--text-light);
}

/* Footer */
.main-footer {
    background: var(--text-color);
    color: var(--white);
    padding: 3rem 0 1rem 0;
    margin-top: 4rem;
}

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

.footer-section h3 {
    margin-bottom: 1rem;
    color: var(--white);
}

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

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

.footer-section ul li a {
    color: rgba(255,255,255,0.8);
    text-decoration: none;
    transition: var(--transition);
}

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

.footer-bottom {
    border-top: 1px solid rgba(255,255,255,0.1);
    padding-top: 1rem;
    text-align: center;
    color: rgba(255,255,255,0.6);
}

/* Enhanced Table of Contents */
.enhanced-toc {
    background: var(--white);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    overflow: hidden;
    margin-bottom: 3rem;
}

.toc-header {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: var(--white);
    padding: 2rem;
    text-align: center;
}

.toc-header h3 {
    font-size: 1.8rem;
    margin-bottom: 0.5rem;
    font-weight: 700;
}

.toc-subtitle {
    font-size: 1rem;
    opacity: 0.9;
    margin: 0;
}

.toc-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 1.5rem;
    padding: 2rem;
}

.toc-card {
    background: var(--white);
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 1.5rem;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.toc-card:hover {
    border-color: var(--primary-color);
    transform: translateY(-5px);
    box-shadow: var(--shadow-hover);
}

.toc-card-highlight {
    background: linear-gradient(135deg, #f8f9ff 0%, #e8f2ff 100%);
    border-color: var(--primary-color);
}

.toc-card-highlight:hover {
    background: linear-gradient(135deg, #f0f4ff 0%, #dae8ff 100%);
}

.toc-icon {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    display: block;
}

.toc-content h4 {
    margin-bottom: 0.75rem;
    font-size: 1.2rem;
    font-weight: 600;
}

.toc-content h4 a {
    color: var(--text-color);
    text-decoration: none;
    transition: var(--transition);
}

.toc-content h4 a:hover {
    color: var(--primary-color);
}

.toc-content p {
    color: var(--text-light);
    font-size: 0.9rem;
    line-height: 1.5;
    margin-bottom: 1rem;
}

.toc-badge {
    display: inline-block;
    background: var(--primary-color);
    color: var(--white);
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.quick-links {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
    margin-top: 1rem;
}

.quick-link {
    background: var(--primary-color);
    color: var(--white);
    padding: 0.4rem 0.8rem;
    border-radius: 6px;
    text-decoration: none;
    font-size: 0.8rem;
    font-weight: 500;
    transition: var(--transition);
}

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

.toc-stats {
    background: #f8f9fa;
    padding: 1.5rem 2rem;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
    gap: 1rem;
    border-top: 1px solid var(--border-color);
}

.toc-stats .stat-item {
    text-align: center;
}

.toc-stats .stat-number {
    display: block;
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 0.25rem;
}

.toc-stats .stat-label {
    display: block;
    font-size: 0.8rem;
    color: var(--text-light);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    font-weight: 600;
}

/* Responsive Design */
@media (max-width: 768px) {
    body {
        margin-left: 0;
    }
    
    .main-nav {
        transform: translateX(-100%);
    }
    
    .main-nav.active {
        transform: translateX(0);
    }
    
    .nav-toggle {
        display: block;
    }
    
    .main-header h1 {
        font-size: 2rem;
    }
    
    .main-header .subtitle {
        font-size: 1.1rem;
    }
    
    .container {
        padding: 0 1rem;
    }
    
    .content-section {
        padding: 2rem 1.5rem;
    }
    
    .overview-grid,
    .features-grid,
    .doc-links {
        grid-template-columns: 1fr;
    }
    
    .quick-start-steps .step {
        flex-direction: column;
        text-align: center;
    }
    
    .header-actions {
        flex-direction: column;
        align-items: center;
    }
}

@media (max-width: 480px) {
    .main-header {
        padding: 2rem 0;
    }
    
    .main-header h1 {
        font-size: 1.8rem;
    }
    
    .content-section {
        margin-bottom: 2rem;
        padding: 1.5rem 1rem;
    }
    
    .overview-card,
    .doc-link {
        padding: 1.5rem;
    }
}

/* Responsive Design for Enhanced TOC */
@media (max-width: 768px) {
    .toc-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
        padding: 1rem;
    }
    
    .toc-header {
        padding: 1.5rem;
    }
    
    .toc-header h3 {
        font-size: 1.5rem;
    }
    
    .toc-card {
        padding: 1rem;
    }
    
    .toc-icon {
        font-size: 2rem;
    }
    
    .toc-stats {
        grid-template-columns: repeat(2, 1fr);
        padding: 1rem;
    }
    
    .quick-links {
        justify-content: center;
    }
}

@media (max-width: 480px) {
    .toc-stats {
        grid-template-columns: 1fr;
    }
    
    .toc-stats .stat-number {
        font-size: 1.5rem;
    }
}