:root {
    --primary-color: #2c3e50;
    --secondary-color: #ecf0f1;
    --accent-color: #3498db;
    --text-color: #333;
    --light-gray: #f5f5f5;
    --medium-gray: #ddd;
    --dark-gray: #777;
}
        
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: #fff;
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
}

figcaption {
    color: var(--dark-gray);
    font-size: 80%;
}

header {
    text-align: left;
    margin-bottom: 2rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid var(--medium-gray);
}

h1 {
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

h2 {
    color: var(--primary-color);
    margin: 1.5rem 0 1rem 0;
    padding-bottom: 0.5rem;
    border-bottom: 1px solid var(--medium-gray);
}

h3 {
    color: var(--primary-color);
    margin: 1.2rem 0 0.5rem;
}

code {
    margin-bottom: 1em;
}

p {
    margin: 0 0 1.5em 0;
}

ul, ol {
    margin: 0 0 0.5em 0;
    padding-left: 2em;
}

li {
    margin-bottom: 0.5em;
}

@media (max-width: 600px) {
    .profile {
        flex-direction: column;
        text-align: center;
    }
    
    nav ul {
        flex-direction: column;
        align-items: center;
    }
    
    nav li {
        margin: 0.3rem 0;
    }
}