.stamp {
  margin: 0 auto;
  padding: 10px 0;
  position: relative;
  width: 60%;
  height: auto;
  background: #add8e6;
  -webkit-filter: drop-shadow(3px 3px 1px black);
  filter: drop-shadow(0px 0px 5px white);
  display: block;
}
.stamp:before {
  position: absolute;
  top: -20px;
  display: block;
  content: "";
  background: radial-gradient(circle, transparent 15px, #add8e6 16px);
  background-size: 50px 40px;
  background-position: -20px -20px;
  width: 100%;
  height: 40px;
  z-index: -1;
}
.stamp:after {
  position: absolute;
  bottom: -20px;
  content: "";
  display: block;
  background: radial-gradient(circle, transparent 15px, #add8e6 16px);
  background-size: 50px 40px;
  background-position: -20px -20px;
  width: 100%;
  height: 40px;
  z-index: -1;
}

/*#ADD8E6
#ececec
*/
