Jukebox-card varible

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"
  - 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:
    name: Nature Sounds
  - 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.

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

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

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.