function searchBoxDefault() {

  var searchBox = document.getElementById( 'search_query' );
  var searchBoxText = 'Search';

  if ( !searchBox ) { return }

  if ( searchBox.value == '' || searchBox.value == searchBoxText ) {
    searchBox.style.color = '#ccc';
    searchBox.value = searchBoxText; 
  }

  searchBox.onfocus = function() {
    searchBox.style.color = '#000';
    if ( searchBox.value == searchBoxText ) { searchBox.value = ''; }
  }

  searchBox.onblur = function() {
    if ( searchBox.value == '' ) {
      searchBox.style.color = '#ccc';
      searchBox.value = searchBoxText;
    }
  };

}

if ( window.addEventListener ) {
  window.addEventListener( "load", searchBoxDefault, false ); 
} else if ( window.attachEvent ) {
  window.attachEvent( "onload", searchBoxDefault );
}