How to prevent "the blink" in Visual Website Optimizer

vwo-blink-prevention.css

.ab-hidden {
    opacity:0 !important;
    filter:alpha(opacity=0) !important;
    background:none !important;
}

vwo-blink-prevention.html

<div id="wrapper" class="ab-hidden">
<!-- YOUR CONTENT HERE -->
</div>

vwo-blink-prevention.js

$(function (){ //Fallback if VWO lib fails to load or control is selected.
   setTimeout(function () {
      $("#wrapper").removeClass("ab-hidden");
  }, 1000); //Change this timer at your will
});