#conteneur2 {
    display: grid;
    grid-template-columns: 1fr 2fr 3fr;
}

#conteneur2 div {
    display: flex;
    height: 50px;
    align-items: center;
    justify-content: center;
    border-style: solid;
    border-width: 1px;
}

#conteneur2 div:nth-child(odd) {
    background-color: rgb(227, 88, 88);
}

#conteneur2 div:nth-child(even) {
    background-color: rgb(122, 205, 130);
}