<div class="header">
    <div class="box">
        <h1>Header</h1>
    </div>
    <div class="box">
        <h2>Sub-header</h2>
    </div>
</div>
Find all elements with the class "box" in the given html section, and remove them. Output the entire html section without the class "box" boxes.
After removing all the elements with the class "box", the resulting HTML section looks like this:

```
<div class="header">
</div>
```