I want to add some space between blocks. I am using bootstrap grid system.

whem I add margin the third div gets down under block 1.

below is my code:

[![enter image description here](https://i.stack.imgur.com/Aufnh.png)](https://i.stack.imgur.com/Aufnh.png)

```
<div style='border:solid black 1px' class='col-md-6'>
  <h1>Block 1</h1>
</div>
<div style='border:solid black 1px' class='col-md-3'>
  <h1>Block 2</h1>
</div>
<div style='border:solid black 1px' class='col-md-3'>
  <h1>Block 3</h1>
</div>

```