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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    line-height: 1.6;
    color: #333;
    overflow-x: hidden;
    background: #f8f9fa;
}

/* Navigation */
.chapter-nav {
    position: fixed;
    top: 0;
    right: 0;
    width: 250px;
    height: 100vh;
    background: rgba(255, 255, 255, 0.95);
    padding: 2rem;
    box-shadow: -2px 0 10px rgba(0, 0, 0, 0.1);
    z-index: 1000;
}

.nav-header {
    font-size: 1.5rem;
    font-weight: bold;
    margin-bottom: 1.5rem;
    color: #1a1a1a;
}

.chapter-nav ul {
    list-style: none;
}

.chapter-nav li {
    margin: 1rem 0;
}

.chapter-nav a {
    text-decoration: none;
    color: #666;
    transition: color 0.3s ease;
    font-size: 1.1rem;
}

.chapter-nav a:hover {
    color: #000;
}

/* Chapter sections */
.chapter {
    min-height: 100vh;
    padding: 4rem 2rem 2rem calc(2rem + 5%);
    max-width: calc(100% - 250px);
    display: flex;
    flex-direction: column;
    justify-content: center;
    position: relative;
    scroll-snap-align: start;
}

/* Introduction section */
#intro {
    background: linear-gradient(135deg, #1a1a1a, #2c3e50);
    color: white;
    text-align: center;
}

#intro h1 {
    font-size: 4rem;
    margin-bottom: 2rem;
    line-height: 1.2;
}

.intro-text {
    font-size: 1.5rem;
    max-width: 800px;
    margin: 0 auto;
    opacity: 0.9;
}

.scroll-indicator {
    position: absolute;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    text-align: center;
    font-size: 1.2rem;
    opacity: 0.8;
}

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

/* Visualization sections */
.visualization {
    width: 100%;
    max-width: 1000px;
    margin: 2rem auto;
    height: 60vh;
    background: white;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    padding: 2rem;
}

.chapter-content {
    max-width: 800px;
    margin: 2rem auto;
    font-size: 1.2rem;
}

/* Impact cards */
.impact-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    max-width: 1200px;
    margin: 2rem auto;
}

.impact-card {
    background: white;
    border-radius: 8px;
    padding: 2rem;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease;
}

.impact-card:hover {
    transform: translateY(-5px);
}

.impact-visual {
    width: 100%;
    height: 200px;
    margin-top: 1rem;
    border-radius: 4px;
    overflow: hidden;
}

/* Future scenarios */
.scenario-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    max-width: 1200px;
    margin: 2rem auto;
}

.scenario {
    background: white;
    border-radius: 8px;
    padding: 2rem;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.scenario-visual {
    width: 100%;
    height: 300px;
    margin-top: 1rem;
    border-radius: 4px;
    overflow: hidden;
}

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

/* Responsive design */
@media (max-width: 1024px) {
    .chapter-nav {
        width: 200px;
    }
    
    .chapter {
        max-width: calc(100% - 200px);
    }
}

@media (max-width: 768px) {
    .chapter-nav {
        width: 100%;
        height: auto;
        bottom: 0;
        top: auto;
        padding: 1rem;
    }
    
    .chapter {
        max-width: 100%;
        padding: 2rem;
    }
    
    .nav-header {
        display: none;
    }
    
    .chapter-nav ul {
        display: flex;
        justify-content: space-around;
    }
    
    .chapter-nav li {
        margin: 0;
    }
    
    .scenario-container {
        grid-template-columns: 1fr;
    }
}