:root {
    --primary-color: #0b5276;
    --secondary-color: #2c5282;
    --accent-color: #d4af37;
    --text-primary: #2d3748;
    --text-secondary: #4a5568;
    --bg-light: #f7fafc;
    --bg-white: #ffffff;
    --border-color: #e2e8f0;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.15);
    --transition: all 0.3s ease;
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.7;
    color: var(--text-primary);
    background-color: var(--bg-light);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
}

/* Header & Navigation */
.navbar {
    background: var(--bg-white);
    box-shadow: var(--shadow);
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
    transition: var(--transition);
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem;
    max-width: 1200px;
    margin: 0 auto;
}

.nav-logo {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary-color);
    text-decoration: none;
}

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

.nav-link {
    text-decoration: none;
    color: var(--text-primary);
    font-weight: 500;
    transition: var(--transition);
    padding: 0.5rem 1rem;
    border-radius: 6px;
}

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

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

.hamburger span {
    width: 25px;
    height: 3px;
    background: var(--primary-color);
    margin: 3px 0;
    transition: var(--transition);
}

/* Main Content */
main {
    margin-top: 70px;
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    padding: 4rem 0;
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 3rem;
    align-items: center;
}

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

.hero-content h2 {
    font-size: 1.5rem;
    margin-bottom: 1.5rem;
    font-weight: 400;
    opacity: 0.9;
}

.hero-description {
    font-size: 1.1rem;
    margin-bottom: 2rem;
    line-height: 1.8;
}

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

.btn {
    padding: 0.75rem 2rem;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition);
    display: inline-block;
    border: none;
    cursor: pointer;
}

.btn-primary {
    background: linear-gradient(135deg, #d4af37 0%, #f4d03f 100%);
    color: var(--primary-color);
}

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

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

.btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.hero-image img {
    width: 100%;
    border-radius: 12px;
    box-shadow: var(--shadow-lg);
}

/* Overview Section */
.overview {
    padding: 4rem 0;
    background: var(--bg-white);
}

.overview h2 {
    text-align: center;
    margin-bottom: 3rem;
    font-size: 2.5rem;
    color: var(--primary-color);
}

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

.overview-card {
    background: linear-gradient(135deg, #f7fafc 0%, #ffffff 100%);
    padding: 2rem;
    border-radius: 12px;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border-top: 3px solid transparent;
}

.overview-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
    background: linear-gradient(135deg, #ffffff 0%, #edf2f7 100%);
    border-top: 3px solid var(--accent-color);
}

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

/* Statistics */
.statistics {
    padding: 4rem 0;
    background: linear-gradient(135deg, #0b5276 0%, #2c5282 50%, #1a4d6b 100%);
    color: white;
}

.statistics h2 {
    text-align: center;
    margin-bottom: 3rem;
    font-size: 2.5rem;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    text-align: center;
}

.stat-item {
    padding: 1.5rem;
}

.stat-number {
    display: block;
    font-size: 3rem;
    font-weight: bold;
    color: var(--accent-color);
    margin-bottom: 0.5rem;
}

.stat-label {
    font-size: 1.1rem;
    opacity: 0.9;
}

/* Timeline Styles */
.timeline-header {
    background: var(--bg-white);
    padding: 2rem 0;
    text-align: center;
}

.timeline-header h1 {
    color: var(--primary-color);
    margin-bottom: 1rem;
    font-size: 2.5rem;
}

.search-container {
    max-width: 600px;
    margin: 2rem auto;
    display: flex;
    gap: 0.5rem;
}

.search-input {
    flex: 1;
    padding: 0.75rem 1rem;
    border: 2px solid var(--border-color);
    border-radius: 8px;
    font-size: 1rem;
    transition: var(--transition);
}

.search-input:focus {
    outline: none;
    border-color: var(--primary-color);
}

.search-btn {
    padding: 0.75rem 1.5rem;
    background: linear-gradient(135deg, #0b5276 0%, #2c5282 100%);
    color: white;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: var(--transition);
}

.search-btn:hover {
    background: linear-gradient(135deg, #2c5282 0%, #0b5276 100%);
    box-shadow: 0 4px 12px rgba(11, 82, 118, 0.4);
    transform: translateY(-2px);
}

.filters {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
    margin-top: 1.5rem;
}

.filter-btn {
    padding: 0.5rem 1.5rem;
    background: var(--bg-light);
    border: 2px solid var(--border-color);
    border-radius: 25px;
    cursor: pointer;
    transition: var(--transition);
    font-weight: 500;
}

.filter-btn.active,
.filter-btn:hover {
    background: linear-gradient(135deg, #0b5276 0%, #2c5282 100%);
    color: white;
    border-color: var(--primary-color);
    box-shadow: 0 2px 8px rgba(11, 82, 118, 0.3);
}

/* Timeline Content */
.timeline-content {
    padding: 3rem 0;
}

.timeline {
    position: relative;
    max-width: 1000px;
    margin: 0 auto;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 50%;
    top: 0;
    bottom: 0;
    width: 4px;
    background: linear-gradient(180deg, #0b5276 0%, #2c5282 50%, #0b5276 100%);
    transform: translateX(-50%);
}

.event {
    position: relative;
    margin: 2rem 0;
    display: flex;
    align-items: flex-start;
    opacity: 0;
    animation: fadeInUp 0.6s ease forwards;
}

.event:nth-child(even) {
    flex-direction: row-reverse;
}

.event:nth-child(even) .event-content {
    margin-right: 3rem;
    margin-left: 0;
}

.event:nth-child(odd) .event-content {
    margin-left: 3rem;
}

.timeline-marker {
    position: absolute;
    left: 50%;
    top: 2rem;
    width: 20px;
    height: 20px;
    background: linear-gradient(135deg, #d4af37 0%, #f4d03f 100%);
    border: 4px solid var(--bg-white);
    border-radius: 50%;
    transform: translateX(-50%);
    z-index: 10;
    box-shadow: 0 4px 8px rgba(212, 175, 55, 0.5);
}

.event-content {
    background: var(--bg-white);
    border-radius: 12px;
    box-shadow: var(--shadow);
    overflow: hidden;
    max-width: 480px;
    transition: var(--transition);
}

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

.event-image {
    width: 100%;
    height: 200px;
    overflow: hidden;
}

.event-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: var(--transition);
}

.event-content:hover .event-image img {
    transform: scale(1.05);
}

.event-details {
    padding: 1.5rem;
}

.event-date {
    background: linear-gradient(135deg, #0b5276 0%, #2c5282 100%);
    color: white;
    padding: 0.25rem 0.75rem;
    border-radius: 15px;
    font-size: 0.9rem;
    font-weight: bold;
    display: inline-block;
    margin-bottom: 1rem;
    box-shadow: 0 2px 4px rgba(11, 82, 118, 0.3);
}

.event-title {
    color: var(--primary-color);
    margin-bottom: 1rem;
    font-size: 1.3rem;
    line-height: 1.4;
}

.event-description {
    line-height: 1.7;
    margin-bottom: 1.5rem;
    text-align: justify;
}

.event-description strong {
    color: var(--primary-color);
}

.event-tags {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.tag {
    background: linear-gradient(135deg, #d4af37 0%, #f4d03f 100%);
    color: var(--primary-color);
    padding: 0.25rem 0.75rem;
    border-radius: 15px;
    font-size: 0.8rem;
    font-weight: 600;
    box-shadow: 0 2px 4px rgba(212, 175, 55, 0.3);
}

/* Glossary Styles */
.glossary-grid {
    display: grid;
    gap: 1.5rem;
}

.glossary-term {
    background: var(--bg-white);
    border-radius: 8px;
    box-shadow: var(--shadow);
    overflow: hidden;
    border-left: 4px solid var(--primary-color);
}

.term-header {
    background: var(--bg-light);
    padding: 1rem 1.5rem;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: var(--transition);
}

.term-header:hover {
    background: linear-gradient(135deg, #0b5276 0%, #2c5282 100%);
    color: white;
}

.term-name {
    font-weight: bold;
    font-size: 1.1rem;
}

.term-content {
    padding: 1.5rem;
    display: none;
}

.term-content.active {
    display: block;
    animation: fadeIn 0.3s ease;
}

.term-definition {
    margin-bottom: 1rem;
    line-height: 1.7;
}

.term-example {
    background: var(--bg-light);
    padding: 1rem;
    border-radius: 6px;
    border-left: 3px solid var(--accent-color);
    margin-top: 1rem;
}

/* Methodology Styles */
.methodology-hero {
    background: linear-gradient(135deg, var(--secondary-color), var(--primary-color));
    color: white;
    padding: 3rem 0;
    text-align: center;
}

.methodology-hero h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.lead {
    font-size: 1.2rem;
    opacity: 0.9;
    max-width: 800px;
    margin: 0 auto;
}

.methodology-content {
    padding: 4rem 0;
}

.methodology-grid {
    display: grid;
    gap: 3rem;
}

.method-card {
    background: var(--bg-white);
    border-radius: 12px;
    box-shadow: var(--shadow);
    overflow: hidden;
    border-top: 4px solid var(--primary-color);
}

.method-card h2 {
    background: var(--bg-light);
    padding: 1.5rem;
    margin: 0;
    color: var(--primary-color);
    font-size: 1.5rem;
}

.method-content {
    padding: 2rem;
}

.method-content h3 {
    color: var(--secondary-color);
    margin: 1.5rem 0 1rem 0;
    font-size: 1.2rem;
}

.method-content ul {
    margin-left: 1.5rem;
    margin-bottom: 1.5rem;
}

.method-content li {
    margin-bottom: 0.5rem;
    line-height: 1.6;
}

.criticism-section {
    background: var(--bg-light);
    padding: 4rem 0;
}

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

.criticism-item {
    background: var(--bg-white);
    padding: 2rem;
    border-radius: 8px;
    box-shadow: var(--shadow);
    border-left: 4px solid var(--accent-color);
}

.criticism-item h3 {
    color: var(--primary-color);
    margin-bottom: 1rem;
}

/* Footer */
footer {
    background: linear-gradient(135deg, #1a202c 0%, #2d3748 50%, #1a202c 100%);
    color: white;
    padding: 2rem 0;
    text-align: center;
}

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

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

/* Responsive Design */
@media (max-width: 768px) {
    .hamburger {
        display: flex;
    }
    
    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background-color: var(--bg-white);
        width: 100%;
        text-align: center;
        transition: 0.3s;
        box-shadow: var(--shadow);
        padding: 2rem 0;
    }
    
    .nav-menu.active {
        left: 0;
    }
    
    .hero {
        grid-template-columns: 1fr;
        text-align: center;
        padding: 2rem 0;
    }
    
    .hero-content h1 {
        font-size: 2rem;
    }
    
    .timeline::before {
        left: 20px;
    }
    
    .event {
        flex-direction: column !important;
        margin-left: 40px;
    }
    
    .event-content {
        margin: 0 !important;
        max-width: 100%;
    }
    
    .timeline-marker {
        left: 20px;
        transform: translateX(-50%);
    }
    
    .overview-grid,
    .stats-grid {
        grid-template-columns: 1fr;
    }
    
    .filters {
        gap: 0.5rem;
    }
    
    .filter-btn {
        padding: 0.4rem 1rem;
        font-size: 0.9rem;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 0.5rem;
    }
    
    .hero-content h1 {
        font-size: 1.5rem;
    }
    
    .search-container {
        flex-direction: column;
    }
    
    .btn {
        padding: 0.6rem 1.5rem;
        font-size: 0.9rem;
    }
}