:before, :after

У заголовка по бокам линии.

by akogch

HTML

<h1 class="line">Текст поверх линии</h1>

CSS

.line {
  position: relative;
  z-index: 1;
  overflow: hidden;
  text-align: center;
}

.line:before,
.line:after {
  content: "";
  display: inline-block;
  width: 100%;
  height: 1px;
  background: #000;
  z-index: -1;
  position: relative;
  vertical-align: middle;
}

.line:before {
  right: 15px;
  margin: 0 0 0 -100%;
}

.line:after {
  left: 15px;
  margin: 0 -100% 0 0;
}