body {
    margin: 0;
    padding: 0;
}

#container1 {
    position: fixed;
    height: 90%;
    width: 100%;
    background-color: green;
}

#inside1{
    position: absolute;
    width: 20%;
    height: 20%;
    background-color: lightgreen;
    bottom: 0;
}

#inside2{
    position: absolute;
    width: 20%;
    height: 20%;
    background-color: lightblue;
    bottom: 0;
    right: 0;
}