// use for containers with absolutely positioned children 
@mixin relative-container ($padding-top: 0, $padding-bottom: 0) {
  position: relative;
 
  @if $padding-top != 0 {
    padding-top: $padding-top;
  }
 
  @if $padding-bottom != 0 {
    padding-bottom: $padding-bottom;
  }
}