title: Extend floating div to 100% width of parent container
body: <p>I have a div container that contains a comment. It is set to float left and the avatar container is next to it (which also floats to the left).
  Here is a screenshot.</p>
  
  <p><img src="https://i.stack.imgur.com/YH0cQ.jpg" alt="enter image description here"></p>
  
  <p>The css of the white comment container:</p>
  
  <pre><code>.comment_content{
      float: left;
  /*
      width: 86%;
  */
      margin-left:5px;
      padding-left: 15px;
      background: url(http://video.chubbyparade.com/img/arrow_left.png) no-repeat 0 8px;
  }
  </code></pre>
  
  <p>I want to set this container to fill 100% of the remaining space in the parent container.</p>
  
  <p>If I set it to width:100%, I get a line break (because it now fills 100% of the parent container's width).</p>
  
  <p>How can I set the comment container to fill the remaining space? I used to do this by setting it to width:86%. But that does not look nice if I resize the window (the layout is NOT fixed width).</p>
  
  <p>A table would be the easy way out. But isn't there a solution with css?</p>