h2 {
  position: relative;
  padding: 1.5rem 2rem;
  border: 3px solid #d8d8d8;
  border-radius: 10px;
  background: #f9f9f9;
}

h2:before {
  position: absolute;
  bottom: -14px;
  left: 1em;
  width: 0;
  height: 0;
  content: '';
  border-width: 14px 12px 0 12px;
  border-style: solid;
  border-color: #d8d8d8 transparent transparent transparent;
}

h2:after {
  position: absolute;
  bottom: -10px;
  left: 1em;
  width: 0;
  height: 0;
  content: '';
  border-width: 14px 12px 0 12px;
  border-style: solid;
  border-color: #f9f9f9 transparent transparent transparent;
}