JSFiddle - React, Tailwind, and code Playground

HTML

<div id="activityList">
    
<div class="aL_userBox">
<a href='profil.php?id=3'>
<img class='aL_userAvatar_small' src='http://thebsreport.files.wordpress.com/2009/07/bum.jpg'><br>
name
</a>
</div>
<div class="aL_Content">
<input class="delButton" type="submit" name="123" value="" style="display: none;">
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</div>

    <div style="clear: both"></div>
<div class="aL_userBox">
<a href='profil.php?id=3'>
<img class='aL_userAvatar_small' src='http://thebsreport.files.wordpress.com/2009/07/bum.jpg'><br>
name
</a>
    </div>
    <div class="aL_Content">
<input class="delButton" type="submit" name="123" value="" style="display: none;">
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</div>

CSS

#activityList{
width: 300px;
height: 300px;
border: 1px solid #000;
overflow: auto;

}
.aL_userAvatar_small{
border: 1px solid grey;
width: 31px;
height: 40px;
}
.aL_userBox{
width: 40px; 
float: left; 
margin: 2px;
}

.aL_Content{
    margin-left: 43px;
    display: block;
}
.delButton{
background: url(http://iconza.com/download/66/16x16/eb3a05/delete.png) no-repeat;
width: 16px;
height: 16px;
border: 0;
float: right;
}

JavaScript

jQuery(document).ready(function($) {
    $('.aL_Content').live('mouseover', function(event) {
      $(this).find('.delButton').show();
    }); 
    $('.aL_Content').live('mouseout', function(event) {
      $(this).find('.delButton').hide();
    }); 
});