title: Change variable X & Y value based on scroll wheel event across browser
body: <p>I'm trying to listen to the scroll wheel event to get the "expected number of pixels scrolled" in a deltaX and deltaY value, and this across browser.
  I am surprised about how few documentation and libraries there is to make this.
  (only the Mozilla MDN even talks about the "wheel" event).</p>
  
  <p>I found two scripts supposed to make this work across browser but I can't make any of those operate properly.</p>
  
  <p><a href="https://developer.mozilla.org/fr/docs/Web/Events/wheel" rel="nofollow noreferrer">https://developer.mozilla.org/fr/docs/Web/Events/wheel</a><br>
  On this page "Listening to this event across browser" section provides a script supposed to solves this issue. 
  I get this error</p>
  
  <pre><code>wheel.js:30 Uncaught TypeError: elem[_addEventListener] is not a function.
  </code></pre>
  
  <p>and also </p>
  
  <p><a href="https://github.com/anvaka/wheel/blob/master/index.js" rel="nofollow noreferrer">https://github.com/anvaka/wheel/blob/master/index.js</a><br>
  With this one, just as the other one I get errors too :</p>
  
  <pre><code>wheel.js:17 Uncaught ReferenceError: module is not defined
  index.js:144 Uncaught ReferenceError: require is not defined
  </code></pre>
  
  <p>Can someone manages to make it work or have another solution ?</p>