The mobile version of my site pulls the same gradient image file as the normal version for my +add button, but my iPhone 4 displays the image as black instead of pink!  I have opened my site on an android phone and it displays pink like it should... What is going on here?!   Please help!!!    www.sororitypin.com         My gradient file URL is: http://sororitypin.com/sites/all/themes/pinboard2/img/button-bg-r.png