Jukebox-card varible

Configuration Frontend
1

Hello, I am using the jukebox-card integration and it works quite well. I wanted to ask for a little help on how to use variables instead of writing the URL directly? This is my code:

type: "custom:jukebox-card"
links:
  - url: http://streams.greenhost.nl:8080/jazz
    name: Concertzender Jazz
  - url: http://fs-insidejazz.fast-serv.com:8282/;stream.nsv
    name: Inside Jazz
  - url: http://stream.srg-ssr.ch/m/rsj/mp3_128
    name: Radio Swiss Jazz
  - url: http://stream.beachlatinoradio.com:8030/;?d=
    name: Beach Latino Radio
  - url: http://streams.calmradio.com/api/43/128/stream/;?d=
    name: Calm Radio
  - url: http://swr-swr1-bw.cast.addradio.de/swr/swr1/bw/mp3/128/stream.mp3
    name: SWR 1
  - url: http://94.23.252.14:8067/stream
    name: Nature Sounds
entities:
  - media_player.wuerfel_wohnzimmer

Sorry, I’ve only recently started using Home Assistant and I would like to understand a bit about how to use variables. Thank you.
2

We need to know what does variables are.
Is it a file, a sensor or sometjong else?

3

I have multiple identical cards, one for each media play. I wanted to create a variable for each URL, so that I could change the URL only once and automatically update all the cards

4

You should be able to just move the links to an include and then use that everywhere.
Look at this video at around 11:08.