[class^="span"]{float:left;box-sizing:border-box;padding:0 20px;width:100%}@media all and (min-width:768px){.span12,.span6{width:100%}.span8,.span4,.span3{width:50%}}@media all and (min-width:980px){.span12{width:100%}.span8{width:calc(100% / 3 * 2)}.span6{width:50%}.span4{width:calc(100% / 3)}.span3{width:25%}}