Rotate a div with CSS by adding a class to it.

css_transform_rotate.css

/* Compass .scss for rotating the div when the class of .open is added to it and rotating back when it is removed */

#direction_arrow {
  position: absolute;
  right: 5px;
  top: 135px;
  cursor: pointer;
  z-index: 999999;
  -webkit-transition: all 0.1s linear;
  &.open {
    -webkit-transform: rotate(-180deg);
    -moz-transform: rotate(-180deg);
    filter: progid:DXImageTransform.Microsoft.BasicImage(rotation=3);
    -webkit-transition: all 0.1s linear;
  }
}