javascript - Jquery dialog change background inside dialog -

i'm working on website , want have book similar dialog. styled dialog , all, , i'm trying make dialog change background open book when user clicks button. problem don't know how should that. i've been searching around couple of hours , haven't come anything.

.custom_dialog_menu {     background: url('01_meny_2.png') !important;      border:0px !important;     width:489px !important;     height:600px !important;     position:fixed !important; } 

that's css , want background change when user presses <div class="forward_button"></div> (which image).

$( "#meny_dialog0" ).dialog({      dialogclass:'custom_dialog_menu',                           resizable: false,      draggable: false,      modal: false,                    autoopen: false,  });  $( ".menu_text" ).click(function() {   $( "#meny_dialog0" ).dialog( "open" );   $(".div0").show(); });  $(".forward_button").click(function () {                              $("meny_dialog0").removeclass('custom_dialog_menu').addclass('custom_dialog_menu_open');              }); 

this dialog initializer , opener , click method.

edit: knew forgot, here click method...

i put hope in guys now, have no idea how fix this. i've tried css, remove , add classes , of without luck.

fiddle: http://jsfiddle.net/fusionsausage/a9y6v/2/

thanks!