Just remove the float in the media query CSS. :)
@media (max-width: 320px) {
.containerright {
float: right; /* remove the float on the mobile media query */
margin: 5px 5px 5px 10px;
position:relative;
}
}
jsFiddle example here.. resize the screen to see what it would look like on a mobile < 320px.
Alternatively, you could just override it in the media query..
@media (max-width: 320px) {
.containerright {
float:none;
}
}