title: Root css is not working for IE browser
body: <p>I use root css to set my background image. It is supported by all other browser but in IE 9+ I am not able to apply background image to css. May be browser is supported for root css.
  I am setting root css variable using javascript.
  I use LESS and Sass css also but did'nt get any way to set css global variable via javascript or JQuery.
  This is my css code:-</p>
  
  <pre><code>:root{
  --mainbgimage: url("image.jpg");
  }
  body{
  background-image: var(--mainbgimage);
  }
  </code></pre>
  
  <p>Is there any way to make this code supported for IE browser
  Javascript code</p>
  
  <pre><code>var image = // image fetched from database;
  document.documentElement.style.setProperty("--mainbgimage", image);
  </code></pre>