How I can use PHP code in a javascript variable?

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Javascript

PHP

HTML5

Hay I want to use my PHP code in a Javascript. Here is my code:

     <script>
    
        var clicked = false;
        val="<?php echo $final; ?> € <?php if ($proz > 0) {echo "<span class=\"badge 
             badge-success\"> $proz %</span>";} else { echo "<span class=\"badge badge- 
             success\"> $minus_cal %</span>";}?>";
        function toggle(){
            if(!clicked){
                clicked = true;
                document.getElementById("btn").innerHTML = "Shown";
                document.getElementById("output").innerHTML = "***";
            } else{
                clicked = false;
                document.getElementById("btn").innerHTML = "Hide";
                document.getElementById("output").innerHTML = val;
            }
        }
</script>

What I have tried:

I think that I know where the issue is. It's the classes inside the span Tag.I tried also so, here it's work but my span is now not formatted.

     <script>
    
        var clicked = false;
        val="<?php echo $final; ?> € <?php if ($proz > 0) {echo "<span> $proz % 
             </span>";} else { echo "<span> $minus_cal %</span>";}?>";
        function toggle(){
            if(!clicked){
                clicked = true;
                document.getElementById("btn").innerHTML = "Shown";
                document.getElementById("output").innerHTML = "***";
            } else{
                clicked = false;
                document.getElementById("btn").innerHTML = "Hide";
                document.getElementById("output").innerHTML = val;
            }
        }
</script>

Thanks for any Help!
Wishes Aaron.