.contChoix {
    display: flex;
    justify-content: space-between;
}

.choix {
    padding: 2em;
    text-align: center;
    width: 50%;
}

.choix p {
    font-size: 1em;
    line-height: 1.3em;
    min-height: 6em;
}

@media (max-width: 640px) {  
    .contChoix {
        display: block;
    }
    .choix {
        padding: 0px;
        text-align: center;
        width: 90%;
        margin: 0px auto;
    }
    .choix p {
        font-size: 1em;
        line-height: 1.3em;
        min-height: none;
    }
    
}