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

body {
    font-family: 'Arial', sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f8f9fa;
}

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

/* Navigation */
.navbar {
    background-color: #2c3e50;
    padding: 1rem 0;
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

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

.nav-logo {
    font-size: 1.5rem;
    font-weight: bold;
    color: white;
}

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

.nav-menu a {
    color: white;
    text-decoration: none;
    transition: color 0.3s;
}

.nav-menu a:hover {
    color: #3498db;
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 120px 0 80px;
    text-align: center;
}

.hero-content h1 {
    font-size: 3.5rem;
    margin-bottom: 1rem;
}

.hero-content h2 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    font-weight: 300;
}

.hero-content p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
}

.cta-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
}

.btn-primary, .btn-secondary {
    padding: 12px 30px;
    border-radius: 25px;
    text-decoration: none;
    font-weight: bold;
    transition: all 0.3s;
}

.btn-primary {
    background-color: white;
    color: #667eea;
}

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

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(0,0,0,0.2);
}

.btn-secondary:hover {
    background-color: white;
    color: #667eea;
}

/* Features Section */
.features {
    padding: 80px 0;
    background-color: white;
}

.features h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: #2c3e50;
}

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

.feature-card {
    background-color: #f8f9fa;
    padding: 2rem;
    border-radius: 10px;
    text-align: center;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    transition: transform 0.3s;
}

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

.feature-card h3 {
    color: #3498db;
    margin-bottom: 1rem;
}

/* Content Sections */
.content-section {
    padding: 100px 0 60px;
    min-height: 100vh;
}

.content-section h1 {
    font-size: 2.5rem;
    color: #2c3e50;
    margin-bottom: 2rem;
}

.content-section h2 {
    font-size: 2rem;
    color: #34495e;
    margin: 2rem 0 1rem;
}

.content-section h3 {
    font-size: 1.5rem;
    color: #3498db;
    margin: 1.5rem 0 1rem;
}

.content-section h4 {
    font-size: 1.2rem;
    color: #2c3e50;
    margin: 1rem 0 0.5rem;
}

.content-section p, .content-section li {
    margin-bottom: 1rem;
    line-height: 1.8;
}

.content-section ul {
    margin-left: 2rem;
}

/* Installation Tabs */
.installation-tabs {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
    border-bottom: 2px solid #ecf0f1;
}

.tab-button {
    padding: 10px 20px;
    background-color: transparent;
    border: none;
    cursor: pointer;
    font-size: 1.1rem;
    color: #7f8c8d;
    transition: all 0.3s;
}

.tab-button.active {
    color: #3498db;
    border-bottom: 3px solid #3498db;
}

.tab-content {
    display: none;
}

.tab-content.active {
    display: block;
}

/* Code Blocks */
pre {
    background-color: #2c3e50;
    color: #ecf0f1;
    padding: 1.5rem;
    border-radius: 8px;
    overflow-x: auto;
    margin: 1rem 0;
}

code {
    font-family: 'Consolas', 'Monaco', monospace;
    font-size: 0.9rem;
}

/* Tutorial Navigation */
.tutorial-nav {
    position: sticky;
    top: 80px;
    background-color: white;
    padding: 1rem;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    margin-bottom: 2rem;
}

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

.tutorial-menu a {
    color: #3498db;
    text-decoration: none;
    font-weight: 500;
}

.tutorial-menu a:hover {
    text-decoration: underline;
}

/* Methodology Steps */
.methodology-steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin: 2rem 0;
}

.step {
    background-color: #f8f9fa;
    padding: 1.5rem;
    border-radius: 8px;
    border-left: 4px solid #3498db;
}

.step h3 {
    color: #2c3e50;
    margin-bottom: 1rem;
}

/* Applications Grid */
.applications-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
    margin: 2rem 0;
}

.app-card {
    background-color: #e8f4f8;
    padding: 1.5rem;
    border-radius: 8px;
    text-align: center;
}

.app-card h3 {
    color: #2980b9;
    margin-bottom: 1rem;
}

/* Output Explanation */
.output-explanation {
    background-color: #f8f9fa;
    padding: 1.5rem;
    border-radius: 8px;
    margin: 1rem 0;
}

/* Responsive Design */
@media (max-width: 768px) {
    .hero-content h1 {
        font-size: 2.5rem;
    }
    
    .nav-menu {
        flex-direction: column;
        gap: 1rem;
    }
    
    .tutorial-menu {
        flex-direction: column;
        gap: 1rem;
    }
    
    .cta-buttons {
        flex-direction: column;
        align-items: center;
    }
}

/* Syntax Highlighting */
.language-r { color: #a8d8ea; }
.language-python { color: #a8d8ea; }

/* Loading Animation */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid #f3f3f3;
    border-top: 3px solid #3498db;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

```css
/* Dataset-specific styles */
.dataset-section {
    margin: 3rem 0;
}

.dataset-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
    margin: 2rem 0;
}

.dataset-card {
    background-color: white;
    border-radius: 10px;
    padding: 2rem;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    border-left: 4px solid #3498db;
}

.dataset-card h3 {
    color: #2c3e50;
    margin-bottom: 1rem;
}

.dataset-info {
    background-color: #f8f9fa;
    padding: 1rem;
    border-radius: 5px;
    margin: 1rem 0;
    font-size: 0.9rem;
}

.dataset-links {
    display: flex;
    gap: 1rem;
    margin: 1rem 0;
}

.btn-download, .btn-tutorial, .btn-example, .btn-dataset {
    padding: 8px 16px;
    border-radius: 5px;
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s;
}

.btn-download {
    background-color: #27ae60;
    color: white;
}

.btn-tutorial, .btn-dataset {
    background-color: #3498db;
    color: white;
}

.btn-example {
    background-color: #e74c3c;
    color: white;
}

.file-structure {
    background-color: #f4f4f4;
    padding: 1rem;
    border-radius: 5px;
    margin-top: 1rem;
}

.file-structure h4 {
    margin-bottom: 0.5rem;
    color: #2c3e50;
}

.preparation-steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin: 2rem 0;
}

.preparation-steps .step {
    background-color: #f8f9fa;
    padding: 1.5rem;
    border-radius: 8px;
    border-left: 4px solid #27ae60;
}

.examples-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin: 2rem 0;
}

.example-card {
    background-color: white;
    padding: 2rem;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    text-align: center;
}

.example-card h3 {
    color: #2c3e50;
    margin-bottom: 1rem;
}

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

.quick-start {
    padding: 60px 0;
    background-color: #f8f9fa;
}

.code-example {
    background-color: white;
    padding: 2rem;
    border-radius: 10px;
    margin: 1rem 0;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.code-example h3 {
    color: #2c3e50;
    margin-bottom: 1rem;
}

.public-data-info {
    background-color: #e8f4f8;
    padding: 2rem;
    border-radius: 10px;
    margin: 2rem 0;
}