Graphing Energy

Hi Ildar,
thanks for these great examples back in december. I could achieve quite a lot but I am struggling at a simple task.

If I want to get the font in bold I have to do what ?

I have searched and looked through your example but did not find.
I have tried

font-style: bold; 
font_style: bold;

but did not succeed. font-style was just a guess after I had seen font-size …
I guess it is super easy but right now I have no clue what to try else.

Final question: if there is a chance to format the value of a sensor in the european number format like “#.##0,00” and not the british / american one ?

Here is an example where I would like to get 2 decimal and thousands for example for euro or cost

  ha-card .states.flex::after {
    color: white;
    font-style: bold;
    font-size: 24px;
    content: "Wh: {{ states('sensor.counter_1_Wh') }} pulses\A €: {{states('sensor.counter_1_euro')}}";
    white-space: pre;
    background-color: rgba(50,50,850,0.9);
    padding: 5px 5px 5px 5px;
    border-radius: 5px;
  }

thx