atom seems to hang during compilation

[kingma-sbw]

in the console it says:
:14 Popping rule because it loops at column 131 of line ' background-image: url(data:image/gif;base64,R0lGODlhFQAJAIAAACMtMP///yH5BAEAAAEALAAAAAAVAAkAAAIXjI+AywnaYnhUMoqt3gZXPmVg94yJVQAAOw==);' Array(4)