oda-framework/tools/styles/theme-editor/index.html

It's an ES Progressive Framework based on the technology of Web Components and designed especially for creating custom UI/UX of any complexity for web and cross-platform PWA mobile applications.

<style scope="tester">
    :root {
        --back-color: lightgray;
    }
</style>

<oda-tester>
    <oda-theme-editor></oda-theme-editor>
</oda-tester>

<script type="module">
    import '../../../oda.js';
    import '../styles.js';
    import './theme-editor.js';
</script>