title: Flutter: Remove padding in buttons - FlatButton, ElevatedButton, OutlinedButton
body: <p>I am looking to remove the default margin of the FlatButton but can't seem to set/override it.</p>
  
  <p><a href="https://i.stack.imgur.com/auKR7.png" rel="noreferrer"><img src="https://i.stack.imgur.com/auKR7.png" alt="buttons with padding"></a></p>
  
  <pre><code>Column(children: &lt;Widget&gt;[
        Container(
            children: [
              FractionallySizedBox(
                widthFactor: 0.6,
                child: FlatButton(
                    color: Color(0xFF00A0BE),
                    textColor: Color(0xFFFFFFFF),
                    child: Text('LOGIN', style: TextStyle(letterSpacing: 4.0)),
                    shape: RoundedRectangleBorder(side: BorderSide.none)))),
        Container(
            margin: const EdgeInsets.only(top: 0.0),
            child: FractionallySizedBox(
                widthFactor: 0.6,
                child: FlatButton(
                    color: Color(0xFF00A0BE),
                    textColor: Color(0xFF525252),
                    child: Text('SIGN UP',
                        style: TextStyle(
                            fontFamily: 'Lato',
                            fontSize: 12.0,
                            color: Color(0xFF525252),
                            letterSpacing: 2.0)))))
      ])
  </code></pre>
  
  <p>I've come across things like <code>ButtonTheme</code> and even <code>debugDumpRenderTree()</code> but haven't been able to implement them properly.</p>