Some CSS modifications

[Zuczek1]

Hello
I'm new here and new with Jellyfin, already installed ElegantFin theme and its perfect
All its running on my Windows PC and works great!
Just as a new in this I have few questions to make my Jellyfin looks perfect.

1) I turn on backdrops effect and its working, but on this theme ElegantFin photos are barely visible,
I tried to find at CSS but I could find any lines responsible for it? Someone has done something like that?

2) In One Seasons TV Show It's any solution to have instead of Season 1 icon complete list of episodes instead?

3) In some movies with longer description I have arrow to expand complete description, but how can I set or what
I can change in CSS to be always extended without clicking on that arrow.

4) I make Home and Favourite button bigger by CMS, but those 4 icons on right stayed small how can I make them bigger?
Same with menu list on the left where is start, media, movies settings etc. It's possible to make it bigger?

5) Last thing I can't make Custom background login to work. I paste it without success. Tried with Enable the splash screen on, off.
Code is below. Maybe I have a mistake somewhere?

:root{
  --loginPageBgUrl: url("http://10.217.5.37:8096/Branding/Splashscreen?format=webp&foregroundLayer=1&quality=33&width=3840&height=2160&blur=2");
}

Thank You for help!
Best regards!