JSFiddle - React, Tailwind, and code Playground

JavaScript

const styles = {
      width: "100%",
      height: "100%",
      background: "this.props.background",
      //"--progress-bar-height": "black"
 };
 
 const props = {
      "--progress-bar-height": "white"
 }
 
 for(let i in props)
 {
   	styles[i] = props[i];   
 }
 
 for(let i in styles)
 {
   	console.log(styles[i]);   
 }