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It probably even happened multiple times, so Earth went from purple to green, back to purple and then green again. And there’s also been periodes where the Earth was mostly covered in ice, making it appear white, called Snowball Earth.
Geo Girl on YouTube has excellent videos about this topic: https://www.youtube.com/watch?v=5sQPcpsOWzg PBS Eons is a good source for a high level overview as well: https://www.youtube.com/watch?v=IIA-k_bBcL0