Main source:

http://backrooms-wiki.wikidot.com/normal-levels-i

Video sources:

https://www.pexels.com/video/woman-drinking-coffee-in-a-yellow-flowering-fields-5271945/
https://pixabay.com/videos/beach-ocean-water-waves-palm-trees-42894/
https://pixabay.com/videos/sea-beach-coast-view-nature-peace-20223/
https://www.pexels.com/video/variety-of-trees-and-plants-in-a-botanical-garden-12906376/
https://www.pexels.com/video/a-green-butterfly-feeding-on-flower-5645610/
https://www.pexels.com/video/crow-flying-from-a-trunk-tree-6137742/
https://www.pexels.com/video/video-of-forest-1448735/
https://pixabay.com/videos/sierra-guadarrama-madrid-oak-trees-21759/
https://pixabay.com/videos/clouds-sky-spin-nature-air-solar-44102/
https://www.pexels.com/video/wooden-bridge-and-a-river-4849125/
https://pixabay.com/videos/man-clouds-mirror-lake-sky-lonely-64729/
https://www.pexels.com/video/woman-doing-a-meditation-on-the-shore-4779429/