Fading a div when scrolling

Fading a div when scrolling

Hello! Hope you're fine! I'm new to jquery. For a couple of hours ago I tried to make a script which fading a div when scrolling down. But I can't make it work. I want the div to fade out more, and more when scrolling. And when scroll back up, I want it to fade in again. Hope you can help me! Thankful for all help!

Please see " Demo".

Div called fade_me
  2. <script src="jquery-1.9.1.js"></script>

  4. <script>

  6. function fade_div() {

  8.   window_scroll = $(this).scrollTop();

  10.   $('#fade_me').css({
  11. 'opacity' : 1-(window_scroll/100)
  12.    });
  13.    
  14. }

  16. </script>