According to the guidelines your signature is against the rules
Avatars and signatures
Avatars may not be larger than 80x80 pixels. We will request you to edit excessive or inappropriate avatars. Failure to comply will lead to avatar removal, restricted account access and possible suspension.
Signatures may not contain graphics, links or commercially-related material. We will request you to edit excessive or inappropriate signatures. Failure to comply will lead to signature removal, restricted account access and possible suspension. You may request an exception regarding this rule, provided there is an explicitly valid reason.