index.html

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>JS-P3</title>
    <link rel="stylesheet" href="style.css">
</head>

<body>

    <h2>Update CSS variable with JS</h2>

    <div class="controls">

        <label for="spacing">Spacing:</label>

        <input type="range" id="spacing" min="10" max="200" value="10" name="spacing" data-sizing="px">

        <label for="blur">Blur:</label>

        <input type="range" id="blur" name="blur" min="0" max="25" value="10" data-sizing="px">

        <label for="base">Base Color</label>

        <input type="color" name="base" id="base" value="#ffc600">

        <label for="height"> Height </label>

        <input type="range" name="height" id="height" min="10" max="100" data-sizing="vh" value="10">

        <label for="rotate"> Rotate </label>

        <input type="range" name="rotate" id="rotate" min="0" max="360" data-sizing="deg" value="0">

        <label for="radius"> Radius </label>

        <input type="range" name="radius" id="radius" min="0" max="100" data-sizing="px" value="0" >

    </div>

    <img src="82528602_845598082535414_6936156667733234811_n.jpg" alt="">

</body>
<script>

    var inputs = document.querySelectorAll(".controls input ");

    function handler(){
        const suffix =this.dataset.sizing || "";
        document.documentElement.style.setProperty(
            `--${this.name}`,
            this.value+suffix
        );
    }

    inputs.forEach(input=>input.addEventListener("change",handler));
    inputs.forEach(input=>input.addEventListener("mousemove",handler));

</script>

</html>