Nephrylis

This is an initial release.

The pack has been tested by me in gameplay on 1.12.6 and 1.21.10, everything works as expected, but there are some things to be improved.

Known issues:

• Dark text is hard to read on a dark background
• Arrows on a servers page and a resource packs page aren't readable enough
• Arrows on a worlds page aren't styled according to the pack
• Some UI elements which don't appear often aren't styled according to the pack