Enable custom submit button styling in Safari mobile

submit.css

/*
*In order to remove native style is possible to set “appearance” to none, 
*thus to enable complete custom styling of our submit buttons we can write the following CSS statement:
*Some notes:
*vendors-specific declarations (-webkit, -moz) may be removed
*do not reset appearance for all the HTML elements (ie: “*”) or you will have to work hard to restyling complex components like select!
*/
input[type='submit']
{
   -webkit-appearance: none;
   -moz-appearance: none;
   appearance: none;  
}