Fills container height containing floating elements without setting `overflow: hidden`.

fill-container-floats.css

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

//or as a mixin
@mixin clearfix {
    &:after {
        content: "";
        clear: both;
        display: table;
    }
}

//usage:
.container {
  @include clearfix;
}