JSFiddle - React, Tailwind, and code Playground

HTML

<!Doctype html>
<html>
    <head>
<style type="text/css">
    /* Normal mode */
    .weight-display div.edit {display:none}
    /* Editor mode */
    .weight-edit div.show {display:none}
</style>
</head>
<body>
<div class="weight-display">
    <button onclick="toggle(this)">Edit this!</button>
    <div class="edit"><select name="Category">
<option value="Department">Department</option>
<option value="Accounts">Accounts</option><option value="Claims">HR</option><option value="Yachts UW">IT</option><option value="Marine Trade">Marketing</option></select></div>
    <div class="show" id='show'>I'm trying to get this to change to the value what is selected when you click "Edit this!" then Save</div>
</div>
<script type="text/javascript">
    function toggle(button)
    {
        // Change the button caption
        button.innerHTML = button.innerHTML=='Edit this!' ? 'Save' : 'Edit this!';
        // Change the parent div's CSS class
        var div = button.parentNode;
        div.className = div.className=='weight-display' ? 'weight-edit' : 'weight-display';
        var s = document.getElementsByTagName('select')[0];
        var val = s.options[s.selectedIndex].value;
        document.getElementById('show').innerHTML = val;
    }
</script>

</body>
</html>