&gt; JavaScript has shown us the value of designing new features in a way that they can be polyfilled or emulated via a preprocessor, so that features can gain adoption without developers having to wait for older browsers to die.<p>Funny you should mention that, I have such a polyfill to introduce Element Query syntax to all browsers IE8 and up, and one of the features we just added was the ability to use variables in your CSS supplied from JavaScript running on the page.<p>Demo: <a href="http:&#x2F;&#x2F;codepen.io&#x2F;tomhodgins&#x2F;pen&#x2F;MKWOWW" rel="nofollow">http:&#x2F;&#x2F;codepen.io&#x2F;tomhodgins&#x2F;pen&#x2F;MKWOWW</a><p>Oh, and we also added a $parent selector to CSS, just for giggles :)<p><a href="http:&#x2F;&#x2F;github.com&#x2F;eqcss&#x2F;eqcss" rel="nofollow">http:&#x2F;&#x2F;github.com&#x2F;eqcss&#x2F;eqcss</a> &lt; it&#x27;s under MIT so feel free to use it and build on it