title: transition effects not happening in Firefox and Opera
body: <p>i tried to create a drop down menu effect using transition effects in css3 .the effects were not being produced in firefox and opera although it was in safari and chrome </p>
  
  <p>for transition i used
  o-transition:height 0.5s;
  -webkit-transition:height 0.5s;
  -moz-transition:height 0.5s;</p>
  
  <p>and the browser i used was mozilla 3.6.15 and opera 10.63
  so please help me why is the transition effect not happening in firefox</p>