#wrapper { width: 300px; height: 300px; border-radius: 100px; overflow: hidden; position: absolute; /* this breaks the overflow:hidden in Chrome/Opera */ -webkit-mask-image: url(data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAIAAACQd1PeAAAAGXRFWHRTb2Z0d2FyZQBBZG9iZSBJbWFnZVJlYWR5ccllPAAAAA5JREFUeNpiYGBgAAgwAAAEAAGbA+oJAAAAAElFTkSuQmCC); /* this fixes the overflow:hidden in Chrome/Opera */ } #box { width: 300px; height: 300px; background-color: #cde; }