Sorry james i am not agree with you because this is the css issue may be Idelle developer do some wrong because in this case we have to write different css for chrome and Firefox, if you want my help please feel fre to ask me.
I have seen your website slider is messed up it look like you give unwanted inline css like margin 2200% what is this this is not valid width margin-left 2200px; same not valid ad mess up the entire header remove it from website may be it is in header or index.php
you should talk to mindbody support they will solve it or give you some solution one time i faced same issue they help me and solve this in just in one day
Thanks
