Bootstrap 3 layout design - layout

Question

How can I make a layout shown in this image
I could have done it easily with grid system but I want the first post's description off the grid system or below the both column. However, for mobile devices I want it to appear with the image or in the same grid like the image below

Answer 1

I don't expect you can do this with Bootstrap's CSS only cause the order of your elements change from desktop to mobile.
Try this html:
<div class="container">
<div class="row">
<div class="col-md-6 col-xs-12" style="background-color:red;">1</div>
<div class="rightblock col-md-6 col-xs-12">
<div class="row">
<div class="col-xs-12" style="background-color:lightgreen;">3</div>
<div class="col-xs-12" style="background-color:lightyellow;">4</div>
</div>
</div>
<div class="clearfix visible-md visible-lg"></div>
<div class="col-md-12 col-xs-12 lefttext" style="background-color:lightblue;">2</div>
</div>
</div>
Where 2 = the caption of your first item (1) and 3 and 4 are your second and third item.
For the mobile version use javascript to swap 2 (.lefttext) and the 3/4 block (.rightblock):
$(window).resize(function () {
if ($(window).width() < 992) {
$(".rightblock").insertAfter($(".lefttext"));
}
});
Demo: http://bootply.com/94560
Note 1: $(window).resize only will called on a real resize (from big to small) and not when opening the small screen direct. See here for better solution to react on screen size changes: How to detect responsive breakpoints of Twitter Bootstrap 3 using JavaScript?
Note 2: see http://getbootstrap.com/css/#grid-responsive-resets for explanation of the clearfix