html, body {
  width: 100vw;
  height: 100vh;
  background: #2C3E50; /* fallback for old browsers */
  background: -webkit-linear-gradient(to left, #2C3E50 , #FD746C); /* Chrome 10-25, Safari 5.1-6 */
  background: linear-gradient(to left, #2C3E50 , #FD746C); /* W3C, IE 10+/ Edge, Firefox 16+, Chrome 26+, Opera 12+, Safari 7+ */
}
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