aside {
    position:fixed;
}

.a-left{
    left:0px;
    bottom:0px;
    width:240px;
    height:240px;
}

.a-left > img {
    width:100%;
    height:100%;
}

.a-right{
    right:0px;
    bottom:0px;
    width:420px;
    height:420px;
}

.a-right > img {
    width:100%;
    height:100%;
}

@media screen and (max-width:1200px) {
    aside {
        display:none;
    }
}

@media screen and (max-width:1200px) {
    aside {
        display:none;
    }
}

@media screen and (max-width:1400px) {
    .a-right {
        right: -70px;
    }
}