Hello!
Since your working with the grid everything should and will stack it's self accordingly to how you code it, laptop and desktop screens are relatively the same size so you wont get that type of layout
It it will only shrink the layout to suit things like tablets, iphones, ipads and smartphones everything should really be done for you
Code:
<div class="row-fluid">
<!-- like to have 12 rows already set up-->
<div class="col-md-12">
<!--I prefer using md rather than xs,lg and sm -->
<div class="col-md-3">
<!-- your content for area "A"-->
</div>
<div class="col-md-3">
<!-- your content for area "B"-->
</div>
<div class="col-md-3">
<!-- your content for area "C"-->
</div>
<div class="col-md-3">
<!-- your content for area "D"-->
</div>
</div>
</div>
and with in each of those cols you could put this to fill in the gaps , it automatically will space and what not, they will display 4 per horizontal row
Code:
<div class="row">
<div class="col-sm-3">
<div class="thumbnail">
<img src="..." alt="...">
<div class="caption">
<h3>Thumbnail label</h3>
<p>...</p>
<p><a href="#" class="btn btn-primary" role="button">Button</a> <a href="#" class="btn btn-default" role="button">Button</a></p>
</div>
</div>
</div>
</div>