title: CSS or JavaScript to highlight certain area of image opacity
body: <p>I'm looking to do something <a href="https://stackoverflow.com/questions/4571059/is-it-possible-to-only-highlight-certain-part-of-image-opacity">like this</a> but with CSS or JavaScript.</p>
  
  <p>I need to highlight a certain part of an image but everything I find is how to do it in Photoshop. Can I do this with CSS or maybe JavaScript? </p>
  
  <p>Am I even asking the right question? </p>
  
  <p>EDIT:</p>
  
  <p>Well here is a <a href="http://jsfiddle.net/MT4T7/" rel="nofollow noreferrer">great submission</a> but I have a follow up question:</p>
  
  <p>I need this for a mobile device and portrait and landscape views as well for many devices like: iOS, iPad, Android, WebOS, Etc... So the fixed position I'm not sure will work.</p>
  
  <p>Any advice?</p>