I've heard this story countless times in the health-sphere.

Cutting out all blue light (LEDs, screens) and sticking exclusively to warm light (yellow/red, toxin-free candles) is a game-changer for improving sleep and healing your natural circadian rhythm.

Fixing the light itself should be priority #1, but if you have no choice (ex: working late somewhere that has piercing LED light), blue-blocker glasses are a must. You will likely notice a sizeable improvement in sleep quality very quickly.