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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f5f5f7;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
    flex: 1;
    display: flex;
    flex-direction: column;
}

/* Header */
header {
    text-align: center;
    padding: 40px 20px;
    margin-bottom: 40px;
}

header h1 {
    font-size: 2.5rem;
    font-weight: 700;
    color: #1d1d1f;
    margin-bottom: 10px;
}

.subtitle {
    font-size: 1.2rem;
    color: #86868b;
}

/* Main Content */
main {
    flex: 1;
}

/* Card Grid */
.card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    margin-bottom: 40px;
}

.card {
    background: white;
    border-radius: 12px;
    padding: 30px;
    text-decoration: none;
    color: inherit;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    transition: transform 0.2s, box-shadow 0.2s;
    display: block;
}

.card:hover {
    transform: translateY(-4px);
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.15);
}

.card h2 {
    font-size: 1.5rem;
    margin-bottom: 12px;
    color: #1d1d1f;
}

.card p {
    color: #86868b;
    font-size: 1rem;
}

/* Content Pages */
.content-page {
    background: white;
    border-radius: 12px;
    padding: 40px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    max-width: 800px;
    margin: 0 auto;
}

.content-page h1 {
    font-size: 2rem;
    margin-bottom: 20px;
    color: #1d1d1f;
    border-bottom: 2px solid #f5f5f7;
    padding-bottom: 15px;
}

.content-page h2 {
    font-size: 1.5rem;
    margin-top: 30px;
    margin-bottom: 15px;
    color: #1d1d1f;
}

.content-page h3 {
    font-size: 1.2rem;
    margin-top: 20px;
    margin-bottom: 10px;
    color: #1d1d1f;
}

.content-page p {
    margin-bottom: 15px;
    line-height: 1.8;
    color: #333;
}

.content-page ul, .content-page ol {
    margin-left: 20px;
    margin-bottom: 15px;
    line-height: 1.8;
}

.content-page li {
    margin-bottom: 8px;
    color: #333;
}

.content-page a {
    color: #0071e3;
    text-decoration: none;
}

.content-page a:hover {
    text-decoration: underline;
}

.content-page .last-updated {
    color: #86868b;
    font-size: 0.9rem;
    font-style: italic;
    margin-top: 30px;
    padding-top: 20px;
    border-top: 1px solid #f5f5f7;
}

.back-link {
    display: inline-block;
    margin-bottom: 20px;
    color: #0071e3;
    text-decoration: none;
    font-weight: 500;
}

.back-link:hover {
    text-decoration: underline;
}

.back-link::before {
    content: "← ";
    margin-right: 5px;
}

/* Footer */
footer {
    text-align: center;
    padding: 30px 20px;
    color: #86868b;
    font-size: 0.9rem;
    margin-top: 40px;
}

/* Responsive Design */
@media (max-width: 768px) {
    header h1 {
        font-size: 2rem;
    }
    
    .subtitle {
        font-size: 1rem;
    }
    
    .card-grid {
        grid-template-columns: 1fr;
        gap: 20px;
    }
    
    .content-page {
        padding: 20px;
    }
    
    .content-page h1 {
        font-size: 1.75rem;
    }
    
    .content-page h2 {
        font-size: 1.3rem;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 15px;
    }
    
    header {
        padding: 30px 15px;
    }
    
    header h1 {
        font-size: 1.75rem;
    }
    
    .content-page {
        padding: 15px;
    }
}