<h2 class="header__right-pulse">Header H2 Long</h2>
<h2 class="header__center-pulse">Header H2</h2>

.header__right-pulse,
.header__center-pulse {
  display: flex;
  text-transform: uppercase;
}
.header__right-pulse:after {
  content: "";
  flex: 1;
  margin-left: 2rem;
  background: red;
}
.header__center-pulse:before {
  content: "";
  flex: 1;
  margin-right: 2rem;
  background: blue;
}
.header__center-pulse:after {
  content: "";
  flex: 1;
  margin-left: 2rem;
  background: green;
}