body {
    font-family: Arial, sans-serif;
    text-align: center;
    margin: 0;
    padding: 0;
}

header {
    padding: 40px 20px;
}

main {
    max-width: 900px;
    margin: auto;
    padding: 20px;
}

section {
    margin: 30px 0;
}

h1 {
    font-size: 42px;
}

h2 {
    font-size: 28px;
}

h3 {
    font-size: 20px;
}

section div {
    margin: 20px 0;
}

footer {
    margin-top: 40px;
    padding: 20px;
}