broken-img.css

img {
  min-height: 50px;
}

img::before { 
  content: " ";
  display: block;

  position: absolute;
  top: -10px;
  left: 0;
  height: calc(100% + 10px);
  width: 100%;
  background-color: rgb(230, 230, 230);
  border: 2px dotted rgb(200, 200, 200);
  border-radius: 5px;
}

img::after { 
  content: " Broken Image of " attr(alt);
  display: block;
  font-size: 16px;
  font-style: normal;
  font-family: inherit;
  color: rgb(100, 100, 100);
  
  position: absolute;
  top: 5px;
  left: 0;
  width: 100%;
  text-align: center;
}