Line break (like <br>) using only css

Solution 1:

It works like this:

h4 {
    display:inline;
}
h4:after {
    content:"\a";
    white-space: pre;
}

Example: http://jsfiddle.net/Bb2d7/

The trick comes from here: https://stackoverflow.com/a/66000/509752 (to have more explanation)

Try

h4{ display:block;}

in your css

http://jsfiddle.net/ZrJP6/

You can use ::after to create a 0px-height block after the <h4>, which effectively moves anything after the <h4> to the next line:

h4 {
  display: inline;
}
h4::after {
  content: "";
  display: block;
}

<ul>
  <li>
    Text, text, text, text, text. <h4>Sub header</h4>
    Text, text, text, text, text.
  </li>
</ul>