title: html5 button background image states
body: <p>I have a button and im trying to apply this image to its background, the green is the off state and yellow is the on click state.  Can I use this image where both states are in same file or do I need to separate them? What is the standard for this situation and how does the css work?</p>
  
  <p><img src="https://i.stack.imgur.com/BSVeQ.gif" alt="enter image description here"></p>
  
  <pre><code>&lt;button&gt;click me&lt;/button&gt;
  button {
      background-image:url('button.png');
  }
  </code></pre>