* {
    margin: 0;
    padding: 0;
}

form {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-self: center;
    margin: 2rem auto;
    width: 25rem;
}

form fieldset {
    padding: 2rem;
    border: 1px solid salmon;
}

fieldset+fieldset {
    margin-top: 1rem;
}

.choix {
    display: flex;
    flex-direction: column;
}

.choix label {
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 5.5rem;
    cursor: pointer;
    padding: .25rem .5rem;
}

.choix>label+label {
    margin-top: 1rem;
}

form button {
    display: block;
    margin: 0 auto;
    padding: .5rem 1rem;
}

.error {
    color: red;
    font-weight: 600;
}

.error:empty {
    display: none;
}

div {
    width: 30rem;
    margin: 1rem auto;
}