JSFiddle - React, Tailwind, and code Playground

HTML

<button onclick="countDown();">-</button>
<span id="counter">0</span>
<button onclick="countUp();">+</button>

<script type="text/javascript">
    var minVal = 0, maxVal = 10, clicks = 0,
 display = document.getElementById("counter");

    function countUp() {
        clicks = Math.min(maxVal, clicks + 1);
        display.innerHTML = clicks;
    }

    function countDown() {
        clicks = Math.max(minVal, clicks - 1);
        display.innerHTML = clicks;
       }
</script>