body {
    margin: 0;
    font-family: sans-serif;
}

header {
    padding: 1rem;
    background-color: #333;
    color: white;
}

h1 {
    margin: 0;
}

nav button {
    margin-bottom: 0.5rem;
    padding: 0.5rem;
    width: 100%;
    cursor: pointer;
    border: none;
    font-size: 1rem;
}

nav button.selected {
    background-color: #833;
    color: white;
}

main {
    display: flex;
}

ul {
    list-style-type: none;
    padding: 0 1rem;
}

section {
    margin: 1rem;
}