Place an object in a corner

There's a red triangle in the bottom right corner of this site. Here's how it is done.
First, paste this HTML into a code block in the footer.

<div>
<a id="corner" href="https://designby.red"></a>
</div>

Add this CSS into the your Custom CSS. Then change the image URL and whatever.

#corner {
    position: fixed;
    bottom: 0;
    z-index: 99999 !important;
    right: 0;
    width: 180px;
    height: 180px;
    text-align: right;
    transition: @transition-fast;
    background: url(https://static1.squarespace.com/static/5914319b1b631b14766825d5/t/5a0ae829e4966b7f020e2d67/1510664233568/red-corner_360.png);
    background-size: contain;
    background-position: center;
    background-repeat: no-repeat;
}

#corner:hover {
  opacity: @opacity-high;
}

@media @640 {
  #corner {
  width: 90px;
  height: 90px; 
    }
}