.main-box {
  position: relative;
  background: hsl(107, 80%, 86%);
  box-shadow: 0px 0px 0px 5px #d7f3d7;
  border: dashed 2px white;
  padding: 0.2em 0.5em;
  color: #454545;
  width: 40%;
  margin: 50px auto 0 auto;
  font-size: 20px;
}
.main-box:after {
  position: absolute;
  content: "";
  right: -7px;
  top: -7px;
  border-width: 0 15px 15px 0;
  border-style: solid;
  border-color: hsl(98, 100%, 77%) #fff hwb(105 53% 0%);
  box-shadow: -1px 1px 1px rgba(0, 0, 0, 0.15);
}
.main-box p {
  margin: 5px;
  padding: 0;
}