Resolved safari bugs

[gwcmk]

Animations on perspective don't work in safari if the parent container has a background-color, details here:

• https://stackoverflow.com/questions/40865842/transformed-child-clipped-by-parent-background-in-safari-irrespective-of-z-inde#
• https://bugs.webkit.org/show_bug.cgi?id=88587

Web Animations API isn't supported by safari yet, so we have to use CSS animations