To test something for CSS borders in nested DIVs, 50 DIVs need to be generated.
In other words, generate

```
<div>
  <div>
    <div>
      ...  total 50 of them nested
    </div>
  </div>
</div>

```

because

```
- 50.times do
  %div 

```

won't do, as they all will be parallel, not nested.