內部DIV下Float後，外部DIV無法撐開

內部DIV下Float後，外部DIV無法撐開

可以在外部DIV加上class='clearfix'

.clearfix:after {
    content: ".";
    display: block;
    height: 0;
    clear: both;
    visibility: hidden;
}
IE
* html .clearfix {height: 1%;}

.clearfix:after {
    content: "";
    display: table;
    clear: both;
}

.clearfix {
    *zoom: 1;
}