:before {
  content: '';
  position: absolute;
  left: 0; right: 0;
  border-top: 1px solid red;
}
.e:after,
.f:after,
.k:after {
  content: '';
  left: 0; right: 0;
  position: absolute;
  border-top: transparent solid 1px;
  border-bottom: 1px solid blue;
  height: 1.2em;
}
div[style*=stretch] div:after {
  content: none;
}
div[style*=stretch] .f:before,
div[style*=stretch] .k:before,
article:last-of-type p:before {
  content: '';
  left: 0; right: 0;
  position: absolute;
  border-bottom: 1px solid blue;