title: Text input with 100% width inside a td expands/continues outside the td
body: <p>Here is the <a href="http://jsbin.com/egusub/edit#source" rel="noreferrer">live demo</a></p>
  
  <p>I'm trying to put a padded text input inside a td, and I want it to occupy 100% of the width, but it goes outside of the td. 
  I don't understand why that happens, anybody knows?</p>
  
  <p>CSS</p>
  
  <pre><code>  table{
      border: solid 1px gray;
      width: 90%;
    }
    input{ width: 100%; padding:10px; }
  </code></pre>
  
  <p>HTML</p>
  
  <pre><code>&lt;table&gt;
    &lt;tr&gt;
      &lt;td style="width:150px;"&gt;Hello&lt;/td&gt;
      &lt;td&gt;&lt;input type='text' value='hihihih'/&gt;&lt;/td&gt;
    &lt;/tr&gt;
  &lt;/table&gt;
  </code></pre>