Critical bug fix day

After seeing some people playing the game, I noticed some bugs that I've fixed.

• The game didn't scale properly in the itch.io web player if the monitor is set to scale (such as a 4K or a Retina display) or if the browser is zooming.
• By the way, there is a fullscreen button now, to make sure that it works on any resolution.
• The game over screen will not glitch and shake anymore.
• The font has more pixels to avoid it looking blurry.