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                <img src="" alt="Nasir al-Mulk Mosque in Iran">


                img {
  display: block;
  width: 100%; 
  mask-position: center;
  mask-repeat: no-repeat;
  mask-size: 100% 100%;
  mask-image: linear-gradient(to bottom, #009485 20%, #fff 20%, #fff 40%, #f44034 40%, #f44034 60%, #000 60%, #000 80%, #2196f3 0);
  mask-mode: luminance

@supports not (mask-mode: luminance) {
  body {
    padding-top: 2em;  
  body::before {    
    content: "Your browser doesn't support mask-mode property";
    display: block;
    color: #e43;
    font-weight: bold;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1;
    line-height: 2em;
    text-align: center;