Change css style HTML5 form required attribute required message

i work with `RTLbootstrap` for `RTL` project. now i have any form with HTML5 form required attribute required message. in action i have this ballon for input: I need To change Like This For RTL: HTML: ``` <div class="controls"> <input class="span4" type="text" name="title" placeholder="Title" value="" required oninvalid="this.setCustomValidity(\'User ID is a must\')"> </div> ``` NOTE:This is not custom tooltip or ballon! if we add required html tag in form input. before submit form `HTML5 form required attribute` show this ballon message automaticly. I need To edit/change/Set CSS For validation message? How To change Display Of required field message for show in `right` of `input` field?