I’m not sure if this is even a border, but I’m trying so hard to find out why is this appearing around the image when I use CSS Sprites on the middle image?

I did tried to set border = 0
#twitter-big {background-position: -0px -503px; width:32px; height:32px; border:0px;}
<a href='http://twitter.com/TwitterID; ?>'><img class="sprites1" id="twitter-big"/></a>
can this somehow coming from the a tag? or what it is really and how to fix that?
It is called outline rather than border. You can set the anchor’s outline property to none to remove it.
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