<div class="main">
  <img src="https://dvyvvujm9h0uq.cloudfront.net/com/articles/1543483387-reinhart-julian-1145947-unsplash.jpg">
</div>
.main {
  position: relative;
  width: 450px;
  padding: 0;
}
.main img{
  width: 100%;
  border-radius: 10px;
}
.main:after {
  content: '';
  position: absolute;
  background: #fff;
  width: 100px;
  height: 50px;
  bottom: 0;
  right: 0;
  border-top-left-radius: 10px;
  text-align: center;
}

External CSS

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External JavaScript

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