Could really use help from a CSS person with getting a gravatar in my comments

I could use some help on getting a gravatar into the right spot in my comments; I’m not much of a CSS person.

I am using the Whitespace theme. It didn’t come with avatar support, and I am trying to add it somewhere that makes sense in the comments. I am trying to place at the top left within the comment text display box (#commenttext) and wrap the comment text around it.

Here is the avatar class I made:

#commenttext .avatar
{
float:left;
padding:2px;
margin:0 0 0.5em 0.5em;
background:none;
border: none;
}

Here is the comments.php snippet. I’ve added the bolded code:

<div class="commenttext">
<strong><span class="avatar">
<?php if(function_exists('get_avatar')){
  echo get_avatar($comment, '50');
} ?>
<span></strong>
<?php comment_text() ?>
</div>

I used SPAN, but also tried DIV.

The problem is that the comment text area shows the image at the top left, but then the comment text begins below the image, not wrapping around it.