I am trying to implement something like a pager here:

And here’s my markup:
<div id="tour-marker-icon-container" class="pagination-centered row-fluid">
<div class="span1">
<button class="btn"><i class="icon-arrow-left"></i></button>
</div>
<div class="span6" id="current-marker-icon-page" data-page-id="1">
@foreach (var markerIcon in Model)
{
<img src="@Url.Content(markerIcon.Path)" data-id="@markerIcon.Id" class="marker-icon"/>
}
</div>
<div class="span1">
<button class="btn"><i class="icon-arrow-right"></i></button>
</div>
</div>
How can I specify the middle column to expand and still keep it responsive? It should look like this:

Update :
span10 seems to work for now but I the right div is out of its parent. Why does this happen?

Also I want to know if there is a way to keep buttons on sides when I resize the window. Here’s the current situation.

Assuming that you want to take up the entire row…
Try changing:
to
There are 12 columns, so span1 + span10 + span1 will give you a total of span12
See the jsFiddle: http://jsfiddle.net/NzSCH/