However, I am very stupid and also a Minecraft tourist who only plays once every few years. The solution to the problem was as follows:
It is the resource pack’s top block texture that determines the colour If you want to change the colour you will have to make a resource pack that does so
While it might be outside of the purview of this channel/server, could someone please explain (very slowly and easily because, as mentioned, I'm an idiot) how to do this? Thanks to anyone who helps in advance!!