body{
    display: block;
    margin: 8px;
}

main{
    width: 40em;
    margin: auto;
}

form{
    display: grid;
    grid-template-columns: [labels] auto [controls]1fr;
    grid-auto-flow: row;
    grid-gap: 10px;
}

form > fieldset {
    grid-column: span 2;
}