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//No JS code available, check HTML and CSS codes

<div class="sidebar">
    This is the sidebar containing some stuff
</div>
 
<div class="content">
    This is the content section. Note that is has no predifined width to it!
</div>

.sidebar{ 
    float:left; 
    width:200px;
    border:1px solid #000000;
    height:200px;
}
 
.content{ 
    overflow:hidden; 
    border:1px solid #333333;
    height:500px;
}