// Sky top ? bottom gradient:
skyTop    = #050c18 // upper sky
skyBottom = #0d1a30 // horizon

// Ground material colours:
groundTop = #3a6b3a // grass top face
platTop   = #3a5a8a // platform top face

// Presets: 🌲 Forest / 🌊 Ocean / 🌋 Volcano / 🌙 Night
// Forest:  sky #071a07 / #0d2e0d  ground #2d6b2d plat #5a4a2a
// Ocean:   sky #050e1a / #0d2040  ground #1a5a7a plat #2a3a9a
// Volcano: sky #1a0505 / #2a0d0d  ground #5a2a1a plat #6a3a1a
// Night:   sky #020208 / #05050f  ground #1a1a3a plat #2a1a4a