remove sprite from thumbnail class

source/less/Core/GFX.less

@@ -2,18 +2,7 @@
 	GFX
 	Icons etc
 ----------------------------------------------------------------- */
-.thumbnail {
+
-	.base-sprite();
-}
-@media only screen and (-webkit-min-device-pixel-ratio: 2), 
-only screen and (min-device-pixel-ratio: 2) {
-	.thumbnail {
-		/* Reference the @2x Sprite */
-		.base-sprite2x();
-		/* Translate the @2x sprite's dimensions back to 1x */
-		background-size: 352px 260px; 
-	}
-}
 /*	Feature Navigation
 ----------------------------------------------------------------- */
 .icon-previous() {