Card-mod - How to use selectors

Hello,
I want to change some elements on a thermostat card. Up to know I have this:

type: thermostat
entity: climate.thermostat_wohnzimmer
name: Wohnzimmer
card_mod:
  style: |
    ha-card {
    --ha-card-background: 
      {% set state = ((states('sensor.luften_wohnzimmer')) | string) %}
      {% if (state == "Egal" ) %}
        {% set color = 'var(var(--paper-toggle-button-unchecked-button-color))' %}
      {% elif (state == "Ja" ) %}
        {% set color = '#145A32' %}
      {% else %}
        {% set color = '#78281F' %}
      {% endif %}
      {{ color }};
    }

This changes the background color depending on a sensor state, works fine.

Now I also want to change the color of the temperature shown in the slider-center. I used the DOM inspector to copy the js path of the div slider-center, copied this to the card-mod-helper and got this as a selector:

“#view>hui-view>hui-masonry-view$#columns>div>hui-card-options>hui-thermostat-card$#slider-center”.

But now I have no idea how to use this selector to change the color. It would be great if someone could point me into the right direction.

Thanks!

ever figure this one out? im also ironically looking for help with the card-mod helper. no idea how im supposed to use the selector it churns out.