title: How to get back border radius of a button:
body: <p>I have this HTML:</p>
  
  <pre><code> &lt;div class="input-group"&gt;
    &lt;input type="email" placeholder="Your email" class="form-control input-lg" name="email"&gt;
     &lt;span class="input-group-btn input-space"&gt;
       &lt;button type="submit" class="btn btn-success btn-lg inline input-space"&gt;Join&lt;/button&gt;
     &lt;/span&gt;
   &lt;/div&gt;
  </code></pre>
  
  <p>where <code>input-space</code> is:</p>
  
  <pre><code>.input-group-btn.input-space {
    padding-left: 15px;
  }
  </code></pre>
  
  <p>Now, here's what I get:
  <a href="https://i.stack.imgur.com/FV4JC.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/FV4JC.jpg" alt="enter image description here"></a></p>
  
  <p>Notice on the left, the button edges are not rounded? It seems to be some rule that Bootstrap applies to <code>input-group-btn</code>, because it expects there will be no space between the input and the button. How can I remove this, so the button has rounded edges on the left side, that are same like the ones already on the right side? I use Bootstrap 3.</p>