title: optimizing images/css for speed performance
body: <p>I have a background image, 1000x666px, and only 93kb. I use it as a background image, with this code:</p>
  
  <pre><code>url(/Optimized-image1.png) no-repeat center center fixed;
  -webkit-background-size: cover;
  -moz-background-size: cover;
  -o-background-size: cover;
  background-size: cover;
  </code></pre>
  
  <p>When i set this image as a background, my jquery effects are very slow and not smooth at all. The same happens with my google maps stuff.</p>
  
  <p>When i set the background just white or any other color, it's all smooth, so I think my CSS-code isn't that good.</p>
  
  <p>I've tried to preload the image with javascript, but that's not good. Also base64 is not working.</p>
  
  <p>Any tips?</p>