Element jumps when using jQuery slideToggle

Question

So, first #metext_hiddentext is hidden until you press #btn_more_metext and then height: 50% will be overwritten by height: auto.

jquery:

<script type="text/javascript">
    $( document ).ready(function() {
        $('#metext_hiddentext').hide();
        $('#btn_more_metext').click(function(){
            $('#me').css( "height", "auto" );
            $('#metext_hiddentext').slideToggle('slow');
        });
    });
</script>

html:

<div id="me">
    <div id="me_content">
     <div id="meimg"></div>
     <div class="metext">
      <h1>I'm Lazor Zombie</h1>
      <h2>Lorem ipsum dolor sit amet.</h2>
      <div id="metext_hiddentext">
      <h2>Lorem ipsum dolor sit amet.</h2>
     </div>
     <div id="btn_more_metext">...</div>
    </div>
</div>

css:

#me {
    background: #ff8400;
    height: 50%;
}


#btn_more_metext { 
    font: 20px/10px "Rosario", 'Ubuntu', sans-serif;
    cursor: pointer;
    width: 80px;
    height: 35px;
    line-height: 22px;

}

Answer 1

Give padding:0 and margin:0 or Add custom margin and padding to <h2> because they have default margins and that is causing jump behavior in your slideToggle().

h2{
   margin:0;
   padding:0;
}

Here is the demo having <h2> tag with custom margin and padding

Answer 2

I think the problem here is, that when div is animated, it has overflow:hidden; And the h2 has some margin on it... so try to remove margin form h2 and add it on the div that is toggeld:

here the fiddle: http://jsfiddle.net/qk8nq/

#me {
    background: #ff8400;
    height: 50%;
}
#metext_hiddentext {
    margin:1em 0;
}

#btn_more_metext { 
    font: 20px/10px "Rosario", 'Ubuntu', sans-serif;
    cursor: pointer;
    width: 80px;
    height: 35px;
    line-height: 22px;

}
h2 {
    padding:0;
    margin:0;
}