Fixed: life counter buttons hidden on mobile

If you tried the new full-screen life counter on your phone and couldn't reach the Cancel, Reset, or Conclude buttons, that's fixed now. The buttons were rendering just off the top of the screen on some mobile browsers, only reappearing after pinch-zooming out. The action bar now stays put no matter how you scrolled to get there, and there's extra spacing at the top for phones with a notch or camera cutout.