vaadin theme demo app is not working for safari browser ,but it is working

Hi ,
      I try to run the vaadin theme demo application in safari browser ,but here themes are not applying when i change the themes while it is working fine for chrome and mozilla browsers.
     Iam also using vaadin themes ,for my application also not working for safari browser. Please give me a solution .
     please find the below link for vaadin theme demo application

        http://demo.vaadin.com/valo-theme/#!common