Running time: 3:37
Grid layouts inherently have padding that prevents the contents in the columns of your grid from extending to the edges of the browser. If you need the contents of your grid to extend from edge to edge in your browser, you can create what is known as an expanded grid by assigned the "expanded" row class to any content section that is using a grid layout.
Note: You'll need to include the collapse row class if you are trying to position an image so that is flush with the left or right edge of the browser.