*{
        box-sizing: border-box;
}

body{
        background-color: aquamarine;
}

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

}

#hijo1{
        width: 20%;
        height: 268px;
        background-color: lightyellow;
}

#hijo2{
        width: 80%;
        height: 268px;
        background-color: rgb(100, 255, 100);
        margin-left: 16px;
        padding: 16px;
}

#nieto1{
        width: 100%;
        height: 236px;
        background-color: rgb(10, 25, 100);
}