Can `!important` be used as an ID or class? YES IT CAN! HTML5LOLZFTW! https://dabblet.com/gist/3a1bcdb58326128f0a13b1424f14a7f4

dabblet.css

/**
 * Can `!important` be used as an ID or class? YES IT CAN! HTML5LOLZFTW!
 * 
 * Visit either:
 * - https://gist.github.com/Potherca/3a1bcdb58326128f0a13b1424f14a7f4
 * - http://dabblet.com/gist/3a1bcdb58326128f0a13b1424f14a7f4
 */

 div {
 	color: lime  !important;
 }
 
 #\!important {
 	color:blue !important;
 }
 .\!important {
 	color:red !important;
 }

dabblet.html

<div id="!important" class="!important">This is important!</div>

dabblet.js

// alert('Hello world!');

settings.json

{"view":"split","fontsize":"100","seethrough":"","prefixfree":"1","page":"all"}