* {
    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: #f5f5f5;
    padding: 20px;
}

main, body > * {
    max-width: 800px;
    margin: 0 auto;
}

h1 {
    font-size: 2.5em;
    margin: 30px 0 20px 0;
    color: #2c3e50;
    border-bottom: 3px solid #3498db;
    padding-bottom: 10px;
}

h2 {
    font-size: 1.8em;
    margin: 25px 0 15px 0;
    color: #34495e;
}

h3 {
    font-size: 1.3em;
    margin: 15px 0 10px 0;
    color: #34495e;
}

p {
    margin: 15px 0;
    text-align: justify;
}

ul {
    margin: 15px 0 15px 30px;
}

li {
    margin: 8px 0;
}

a {
    color: #3498db;
    text-decoration: none;
    transition: color 0.3s ease;
}

a:hover {
    color: #2980b9;
    text-decoration: none;
}

span {
    display: block;
    margin-top: 10px;
    font-weight: 600;
    color: #555;
}

br {
    margin-bottom: 10px;
}

strong, b {
    color: #2c3e50;
    font-weight: 600;
}