*{
    box-sizing: border-box;
}

body{
    background-color: aquamarine;
}

#padre{
    width: 90%;
    height: 300px;
    margin: 10px auto;
    background-color: blue;
    padding: 16px;
    display: flex;
}

#hijo1{
    width: 20%;
    height: 270px;
    background-color: rgb(145, 30, 97);
}

#hijo2{
    width: 60%;
    height: 270px;
    background-color: rgb(202, 199, 18);
    margin-left: 16px;
}

#hijo3{
    width: 20%;
    height: 270px;
    background-color: rgb(32, 133, 216);
    margin-left: 16px;
}