Input with Disappearing Background Image

This replicates the functionality of the standard embeddable Google Search fields. They have an image in the background and when the input is clicked into, the image disappears.

<form name="searchform" id="search-form">
   <div>
       <b>Search</b>
       <input type="text" name="txtInput" title="Enter the terms you wish to search for." />
       <input type="submit" value="GO!" class="submit" style="cursor: pointer;" />
   </div>
</form>

JavaScript underneath form markup:

<script type="text/javascript" language="javascript">
 (function() {
    var id = document.getElementById('search-form');
    if (id && id.txtInput) {
      var name = id.txtInput;
      var unclicked = function() {
          if (name.value == '') {
              name.style.background = '#FFFFFF url(images/googbg.png) left no-repeat';
          }
       };
       var clicked = function() {
          name.style.background = '#ffffff';
       };
    name.onfocus = clicked;
    name.onblur = unclicked;
    unclicked();
    }
  })();
</script>

View Demo