twbs/bootstrap — pull request #13519 by Dakuan (2014-05-06 09:54:00+00:00)
Title: at-breakpoint

This feature allows you to apply different styles to elements based on the screen width:

Usage:

``` LESS
// arbitrary width
.thing {
.at-breakpoint(100px, {
background-color: red;
});
.at-breakpoint(200px, {
background-color: green;
});
}

// bootstrap cols
.thing {
background-color: blue;
.at-md({
background-color: yellow;
});
}
```