Hello World!

Resize the browser window to see the effect.

.col-xs-7 .col-sm-6 .col-lg-8

.col-xs-5 .col-sm-6 .col-lg-4

.col-xs-6 .col-sm-8 .col-lg-10

.col-xs-6 .col-sm-4 .col-lg-2

.col-xs-6 .col-sm-8 .col-lg-10

.col-xs-6 .col-sm-12 .col-lg-2

.col-xs-6

.col-xs-6