If you decide to adjust the sequence of elements, a pure CSS/HTML approach could look like this:
Take a look at this jsFiddle example - experiment by resizing the window
HTML
<div class='box'>
<div class='right'>content right</div>
<div class='left'>content left</div>
</div>
CSS
.left {
background:red;
height:200px;
width:50%;
float:left;
}
.right {
background:blue;
height:200px;
width:50%;
float:right;
}
@media screen and (max-width: 481px) {
.left {
width:100%;
float:none;
}
.right {
width:100%;
float:none;
}
}
If that method doesn't suit your needs, there's an alternative where the element order remains unchanged. Since you're interested in jQuery, check out this solution:
Here's another jsFiddle example - resize the window to see it in action
HTML
<div class='box'>
<div class='left'>content left</div>
<div class='right'>content right</div>
</div>
jQuery
$(window).resize(function(){
if ($(window).width() <= 481){
$('.right').insertBefore('.left');
}
else {
$('.right').insertAfter('.left');
}
});