twitter/bootstrap — pull request #1923 by hecticjeff (2012-02-12 13:22:35+00:00)
Title: Fix responsive css for 768px width

When a device is *exactly* 768px wide (e.g. a portrait iPad) it uses 2
sets of conflicting `@media` rules. This fix simply adds a pixel to
the "portrait tablet to default desktop" rule.

Before the fix is applied, `.row` has `margin-left: -20px` applied.

![Before fix](http://f.cl.ly/items/3E1X1H0c2g321b3D191o/photo%201.PNG)

With the fix, devices at 768px have correct alignment.

![After fix](http://f.cl.ly/items/0n0b2E1x121V1h3b0q0K/photo%202.PNG)