title: Css button pressing effect
body: <p>I have a button with a  box-shadow that makes it look like it's floating, and I would like to make a pressing effect when I click on it:</p>
  
  <p>Code(CSS):</p>
  
  <pre><code>#startBtn
  {
      font-family: OpenSans;
      color: #FFFFFF;
      background-color: #00FF7C;
      border: 1px solid #00FF7C;
      border-radius: 5px;
      box-shadow: 0px 5px 0px #00823F;
  }
  </code></pre>
  
  <p>Code(HTML):</p>
  
  <pre><code>&lt;input type="button" id="startBtn" value="Let's begin"&gt;
  </code></pre>
  
  <p>Screenshot:</p>
  
  <p><a href="https://i.stack.imgur.com/KaGS2.png" rel="noreferrer"><img src="https://i.stack.imgur.com/KaGS2.png" alt="Button"></a></p>