Moonlight edition

• New dark style contributed by @EwanGreen4 (personally love the look!!)
• Background light animations in dark mode (shift+D to toggle)
• Adjust the colours in the ptcollage style to be more balanced.
• Allow styles to adjust the unit note colours.
• Don't draw highlights on the left side of notes for background units, to make it easier to see the foreground unit.
• Bugfix: clicking on the left piano doesn't accidentally trigger sounds from other units
• Bugfix: playhead following works on 2x zoom now

Check out the new style and animations below!

untitled.mp4