Untitled

  <div></div>

div {

  position: relative;

  background-image: url(http://placehold.it/500x200);

  width: 500px;

  height: 200px;

  box-shadow: inset 0 0 4px 1px black;

  overflow: hidden;

}

div::after, div::before {

  content: '';

  position: absolute;

  width: 50%;

  height: 30px;

  background-color: white;

  bottom: 0;

  box-shadow: 0 0 4px 1px black;

}

div::after {

  right: -15px;

  transform: skewX(-45deg);

}

div::before {

  left: -15px;

  transform: skewX(45deg);

}