@sdetweil
OK, I looked into it, thank you.
Now, I have this images from Fontawesome. It looks nice, but I would like to be able to use other image if needed.

For example, I would replace the “sun” with a picture “04n.png” in the “icons” forder on my raspberry.

I tried to change line 251 with 250 in the custom.css file

Now, the result is, that the sun has disappeared (correct), but just has been replaced with a gap.

do you maybe see a mistake in my custom.css file? the problem is maybe between lines 221 and 240. this is strange…