width: 33%;
margin: .25em 1em .5em 0;
}
+ .left .left, .left .right,
+ .right .left, .right .right,
+ .half .left, .half .right {
+ float: none;
+ width: 100%;
+ margin: .25em 0 .5em 0;
+ }
section.left > :first-child,
section.right > :first-child {
float: none;