Hi @FufsowyFufs, welcome to the forum.
You'll find the folk here very helpful but we really appreciate a good topic and correctly formatted code.
When you post code or a flow please put three back ticks on a line above and below, like this...
```
code here
```
Secondly, a more appropriate topic title really helps the right forum member understand if they can help. For example, this topic should probably be titled "can't change button background colour".
Anyhow, a quick search lead to this. Might be helpful?