title: Divide div to left, right , bottom in html
body: <p>This is the layout i want,</p>
  
  <p><img src="https://i.stack.imgur.com/Gqpcj.png" alt="enter image description here"></p>
  
  <p>I made some with code, but i'm not sure how to do after this.</p>
  
  <p>[html]</p>
  
  <pre><code>  &lt;div id="content"&gt;
          &lt;div id="left"&gt;left&lt;/div&gt;
          &lt;div id="right"&gt;right&lt;/div&gt;
          &lt;div id="bottom"&gt;bottom&lt;/div&gt;    
      &lt;/div&gt;
  </code></pre>
  
  <p>[css]</p>
  
  <pre><code>  #content{
          /* the width in here will be changed 
          width: this requirment will be changed
          i dont' want to type my left, right content static
          is there a way? */
      }
      #left{
          float:left;
          width: 50px;
      }
      #right{
          float:left;
          width: 50px;
      }
      #bottom{
          /*what do i have to do in here?
          float:*/
      }
  </code></pre>