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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: #333;
    line-height: 1.6;
    overflow-x: hidden;
}

/* Hero Section */
.hero {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    color: white;
    padding: 2rem;
    position: relative;
}

.hero h1 {
    font-size: 4rem;
    font-weight: 800;
    margin-bottom: 1rem;
    text-shadow: 2px 2px 20px rgba(0, 0, 0, 0.3);
    animation: fadeInUp 1s ease;
}

.hero-subtitle {
    font-size: 1.5rem;
    font-weight: 300;
    margin-bottom: 3rem;
    opacity: 0.9;
    animation: fadeInUp 1s ease 0.2s both;
}

.hero-stats {
    display: flex;
    gap: 4rem;
    margin-bottom: 4rem;
    animation: fadeInUp 1s ease 0.4s both;
}

.stat {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.stat-number {
    font-size: 3rem;
    font-weight: 700;
    color: #ffd700;
}

.stat-label {
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    opacity: 0.8;
}

.scroll-indicator {
    position: absolute;
    bottom: 2rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
    animation: fadeInUp 1s ease 0.6s both;
}

.scroll-indicator span {
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 2px;
}

.scroll-arrow {
    font-size: 2rem;
    animation: bounce 2s infinite;
}

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

@keyframes bounce {
    0%, 20%, 50%, 80%, 100% {
        transform: translateY(0);
    }
    40% {
        transform: translateY(-10px);
    }
    60% {
        transform: translateY(-5px);
    }
}

/* Progress Bar */
.progress-container {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: rgba(255, 255, 255, 0.2);
    z-index: 1000;
}

.progress-bar {
    height: 100%;
    background: linear-gradient(90deg, #667eea, #ffd700);
    width: 0%;
    transition: width 0.1s ease;
}

/* Sidebar Navigation */
.sidebar-nav {
    position: fixed;
    right: 2rem;
    top: 50%;
    transform: translateY(-50%);
    z-index: 100;
    background: rgba(255, 255, 255, 0.95);
    padding: 1.5rem 1rem;
    border-radius: 12px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.2);
    max-width: 200px;
}

.nav-header {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 2px;
    color: #999;
    margin-bottom: 1rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid #eee;
}

.nav-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.75rem;
    margin: 0.25rem 0;
    text-decoration: none;
    color: #666;
    border-radius: 8px;
    transition: all 0.3s ease;
    cursor: pointer;
}

.nav-item:hover {
    background: #f0f0f0;
    transform: translateX(-5px);
}

.nav-item.active {
    background: linear-gradient(135deg, #667eea, #764ba2);
    color: white;
    transform: translateX(-5px);
}

.nav-number {
    font-size: 0.75rem;
    font-weight: 700;
    opacity: 0.6;
}

.nav-title {
    font-size: 0.85rem;
    font-weight: 500;
}

/* Dashboard Container */
.dashboard-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 2rem;
    background: white;
}

/* Chapter Sections */
.chapter {
    min-height: 100vh;
    padding: 4rem 2rem;
    display: flex;
    flex-direction: column;
    justify-content: center;
    scroll-margin-top: 2rem;
}

.chapter-header {
    margin-bottom: 3rem;
    max-width: 800px;
}

.chapter-number {
    display: inline-block;
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 3px;
    color: #667eea;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.chapter-title {
    font-size: 3rem;
    font-weight: 800;
    color: #1a202c;
    margin-bottom: 1rem;
    line-height: 1.2;
}

.chapter-description {
    font-size: 1.2rem;
    color: #666;
    line-height: 1.8;
}

/* Chart Cards */
.chart-card {
    background: white;
    border-radius: 12px;
    padding: 2rem;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.chart-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.12);
}

/* Conclusion Section */
.conclusion {
    padding: 6rem 2rem;
    text-align: center;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border-radius: 20px;
    margin: 4rem 0;
}

.conclusion h2 {
    font-size: 3rem;
    margin-bottom: 2rem;
}

.conclusion > p {
    font-size: 1.2rem;
    max-width: 800px;
    margin: 0 auto 4rem;
    line-height: 1.8;
    opacity: 0.95;
}

.key-insights {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.insight {
    background: rgba(255, 255, 255, 0.1);
    padding: 2rem;
    border-radius: 12px;
    backdrop-filter: blur(10px);
}

.insight h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
}

.insight p {
    font-size: 1rem;
    opacity: 0.9;
}

/* Responsive Design */
@media (max-width: 1024px) {
    .sidebar-nav {
        display: none;
    }
    
    .hero h1 {
        font-size: 3rem;
    }
    
    .chapter-title {
        font-size: 2.5rem;
    }
}

@media (max-width: 768px) {
    .hero h1 {
        font-size: 2.5rem;
    }
    
    .hero-stats {
        flex-direction: column;
        gap: 2rem;
    }
    
    .chapter-title {
        font-size: 2rem;
    }
    
    .chapter-description {
        font-size: 1rem;
    }
}