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

:root {
    --primary-color: #1e3a8a;
    --secondary-color: #06b6d4;
    --accent-color: #f97316;
    --text-dark: #1f2937;
    --text-light: #6b7280;
    --bg-light: #f8fafc;
    --white: #ffffff;
    --gradient-primary: linear-gradient(135deg, #1e3a8a 0%, #06b6d4 100%);
    --gradient-accent: linear-gradient(135deg, #f97316 0%, #ea580c 100%);
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
}

body {
    font-family: 'Georgia', serif;
    line-height: 1.6;
    color: var(--text-dark);
    overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
    font-family: 'Inter', sans-serif;
    font-weight: 600;
    line-height: 1.2;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.section {
    padding: 80px 0;
}

.section-title {
    font-size: 2.5rem;
    text-align: center;
    margin-bottom: 3rem;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.bg-light {
    background-color: var(--bg-light);
}

/* Navigation */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    z-index: 1000;
    transition: all 0.3s ease;
    box-shadow: var(--shadow-sm);
}

.navbar.scrolled {
    background: rgba(255, 255, 255, 0.98);
    box-shadow: var(--shadow-md);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-family: 'Inter', sans-serif;
    font-weight: 700;
    font-size: 1.2rem;
    color: var(--primary-color);
}

.nav-logo i {
    font-size: 1.5rem;
    color: var(--secondary-color);
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-link {
    text-decoration: none;
    color: var(--text-dark);
    font-weight: 500;
    transition: color 0.3s ease;
    position: relative;
}

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

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--secondary-color);
    transition: width 0.3s ease;
}

.nav-link:hover::after {
    width: 100%;
}

.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
}

.hamburger span {
    width: 25px;
    height: 3px;
    background: var(--text-dark);
    margin: 3px 0;
    transition: 0.3s;
}

/* Hero Section */
.hero {
    height: 100vh;
    position: relative;
    display: flex;
    align-items: center;
    overflow: hidden;
}

.hero-background {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -2;
}

.hero-bg-image {
    width: 100%;
    height: 100%;
    object-fit: cover;
    opacity: 0.3;
}

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, rgba(30, 58, 138, 0.8) 0%, rgba(6, 182, 212, 0.6) 100%);
    z-index: -1;
}

.hero-content {
    text-align: center;
    color: var(--white);
    max-width: 800px;
    margin: 0 auto;
}

.hero-title {
    font-size: 3.5rem;
    margin-bottom: 2rem;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
}

.hero-meta {
    display: flex;
    justify-content: center;
    gap: 2rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

.hero-meta > div {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 1rem;
    opacity: 0.9;
}

.hero-description {
    font-size: 1.2rem;
    margin-bottom: 3rem;
    opacity: 0.9;
    line-height: 1.6;
}

.cta-button {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    background: var(--gradient-accent);
    color: var(--white);
    padding: 15px 30px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    box-shadow: var(--shadow-lg);
}

.cta-button:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-xl);
}

/* Fundamentals Section */
.fundamentals-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.fundamental-card {
    background: var(--white);
    padding: 2rem;
    border-radius: 15px;
    box-shadow: var(--shadow-md);
    text-align: center;
    transition: all 0.3s ease;
    border: 1px solid rgba(6, 182, 212, 0.1);
}

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

.card-icon {
    width: 80px;
    height: 80px;
    background: var(--gradient-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1.5rem;
    color: var(--white);
    font-size: 2rem;
}

.fundamental-card h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: var(--primary-color);
}

/* Technical Section */
.technical-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.tech-item {
    margin-bottom: 2rem;
}

.tech-item h3 {
    display: flex;
    align-items: center;
    gap: 1rem;
    font-size: 1.3rem;
    margin-bottom: 1rem;
    color: var(--primary-color);
}

.tech-item i {
    color: var(--secondary-color);
}

.tech-diagram {
    width: 100%;
    border-radius: 15px;
    box-shadow: var(--shadow-lg);
}

/* Applications Section */
.applications-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.app-card {
    background: var(--white);
    padding: 2rem;
    border-radius: 15px;
    box-shadow: var(--shadow-md);
    transition: all 0.3s ease;
    border-left: 4px solid var(--secondary-color);
}

.app-card:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-lg);
}

.app-icon {
    width: 60px;
    height: 60px;
    background: var(--gradient-primary);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1rem;
    color: var(--white);
    font-size: 1.5rem;
}

.app-card h3 {
    font-size: 1.3rem;
    margin-bottom: 1rem;
    color: var(--primary-color);
}

/* Education Section */
.education-hero {
    text-align: center;
    margin-bottom: 4rem;
}

.education-image {
    width: 100%;
    max-width: 600px;
    border-radius: 20px;
    box-shadow: var(--shadow-xl);
}

.education-applications {
    margin-bottom: 4rem;
}

.education-applications h3 {
    font-size: 2rem;
    text-align: center;
    margin-bottom: 2rem;
    color: var(--primary-color);
}

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

.edu-app-card {
    background: var(--white);
    padding: 2rem;
    border-radius: 15px;
    box-shadow: var(--shadow-md);
    border: 1px solid rgba(6, 182, 212, 0.1);
}

.edu-app-header {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1rem;
}

.edu-app-header i {
    font-size: 1.5rem;
    color: var(--secondary-color);
}

.edu-app-header h4 {
    font-size: 1.3rem;
    color: var(--primary-color);
}

.citation {
    font-style: italic;
    color: var(--text-light);
    font-size: 0.9rem;
    margin-top: 1rem;
    padding-top: 1rem;
    border-top: 1px solid rgba(6, 182, 212, 0.2);
}

.potential-uses {
    margin-bottom: 4rem;
}

.potential-uses h3 {
    font-size: 2rem;
    text-align: center;
    margin-bottom: 2rem;
    color: var(--primary-color);
}

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

.potential-card {
    background: var(--white);
    padding: 2rem;
    border-radius: 15px;
    box-shadow: var(--shadow-md);
    text-align: center;
    border: 2px solid transparent;
    transition: all 0.3s ease;
}

.potential-card:hover {
    border-color: var(--secondary-color);
    transform: translateY(-3px);
}

.potential-card i {
    font-size: 3rem;
    color: var(--secondary-color);
    margin-bottom: 1rem;
}

.potential-card h4 {
    font-size: 1.3rem;
    margin-bottom: 1rem;
    color: var(--primary-color);
}

.limitations h3 {
    font-size: 2rem;
    text-align: center;
    margin-bottom: 2rem;
    color: var(--primary-color);
}

.limitations-list {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.limitation-item {
    display: flex;
    align-items: flex-start;
    gap: 1.5rem;
    background: var(--white);
    padding: 2rem;
    border-radius: 15px;
    box-shadow: var(--shadow-md);
}

.limitation-item i {
    font-size: 2rem;
    color: var(--accent-color);
    margin-top: 0.5rem;
}

.limitation-item h4 {
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
    color: var(--primary-color);
}

/* Timeline */
.timeline {
    position: relative;
    max-width: 800px;
    margin: 0 auto;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 50%;
    top: 0;
    bottom: 0;
    width: 2px;
    background: var(--secondary-color);
    transform: translateX(-50%);
}

.timeline-item {
    position: relative;
    margin-bottom: 3rem;
}

.timeline-marker {
    position: absolute;
    left: 50%;
    top: 0;
    width: 60px;
    height: 60px;
    background: var(--gradient-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--white);
    font-size: 1.5rem;
    transform: translateX(-50%);
    z-index: 2;
}

.timeline-content {
    background: var(--white);
    padding: 2rem;
    border-radius: 15px;
    box-shadow: var(--shadow-md);
    margin-left: 50%;
    margin-left: calc(50% + 50px);
    width: calc(50% - 50px);
}

.timeline-item:nth-child(even) .timeline-content {
    margin-left: 0;
    margin-right: calc(50% + 50px);
}

.timeline-content h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: var(--primary-color);
}

.timeline-content ul {
    list-style: none;
    padding-left: 0;
}

.timeline-content li {
    margin-bottom: 1rem;
    padding-left: 1.5rem;
    position: relative;
}

.timeline-content li::before {
    content: '→';
    position: absolute;
    left: 0;
    color: var(--secondary-color);
    font-weight: bold;
}

.adoption-strategy {
    margin-top: 4rem;
}

.adoption-strategy h3 {
    font-size: 2rem;
    text-align: center;
    margin-bottom: 2rem;
    color: var(--primary-color);
}

.strategy-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 3rem;
    align-items: center;
}

.key-questions {
    background: var(--bg-light);
    padding: 2rem;
    border-radius: 15px;
    margin: 2rem 0;
}

.key-questions h4 {
    font-size: 1.3rem;
    margin-bottom: 1rem;
    color: var(--primary-color);
}

.key-questions ol {
    padding-left: 1.5rem;
}

.key-questions li {
    margin-bottom: 0.5rem;
    font-weight: 500;
}

.brain-image {
    width: 100%;
    border-radius: 20px;
    box-shadow: var(--shadow-lg);
}

/* Citations Section */
.citations-content {
    max-width: 900px;
    margin: 0 auto;
}

.citation-note {
    background: var(--white);
    padding: 2rem;
    border-radius: 15px;
    box-shadow: var(--shadow-md);
    margin-bottom: 3rem;
    text-align: center;
    border-left: 4px solid var(--accent-color);
}

.references-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.reference-item {
    background: var(--white);
    padding: 1.5rem;
    border-radius: 10px;
    box-shadow: var(--shadow-sm);
    border-left: 3px solid var(--secondary-color);
}

.reference-item a {
    color: var(--secondary-color);
    text-decoration: none;
}

.reference-item a:hover {
    text-decoration: underline;
}

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

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

.footer-section h3 {
    font-size: 1.3rem;
    margin-bottom: 1rem;
    color: var(--secondary-color);
}

.social-links {
    display: flex;
    gap: 1rem;
}

.social-links a {
    width: 40px;
    height: 40px;
    background: var(--secondary-color);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--white);
    text-decoration: none;
    transition: all 0.3s ease;
}

.social-links a:hover {
    background: var(--accent-color);
    transform: translateY(-2px);
}

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

/* Responsive Design */
@media (max-width: 768px) {
    .hamburger {
        display: flex;
    }
    
    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background-color: var(--white);
        width: 100%;
        text-align: center;
        transition: 0.3s;
        box-shadow: var(--shadow-lg);
        padding: 2rem 0;
    }
    
    .nav-menu.active {
        left: 0;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .hero-meta {
        flex-direction: column;
        gap: 1rem;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .technical-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .timeline::before {
        left: 20px;
    }
    
    .timeline-marker {
        left: 20px;
        transform: none;
    }
    
    .timeline-content {
        margin-left: 60px;
        width: calc(100% - 60px);
    }
    
    .timeline-item:nth-child(even) .timeline-content {
        margin-left: 60px;
        margin-right: 0;
    }
    
    .strategy-content {
        grid-template-columns: 1fr;
    }
    
    .fundamentals-grid,
    .applications-grid,
    .edu-apps-grid,
    .potential-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }
    
    .section {
        padding: 60px 0;
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .hero-description {
        font-size: 1rem;
    }
    
    .fundamental-card,
    .app-card,
    .edu-app-card,
    .potential-card {
        padding: 1.5rem;
    }
}

/* Smooth Scrolling */
html {
    scroll-behavior: smooth;
}

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

.fade-in-up {
    animation: fadeInUp 0.6s ease-out;
}

/* Hover Effects */
.app-card:hover .app-icon {
    transform: scale(1.1);
    transition: transform 0.3s ease;
}

.fundamental-card:hover .card-icon {
    transform: scale(1.1);
    transition: transform 0.3s ease;
}