Edit in JSFiddle

body{
  background: -moz-linear-gradient(45deg,rgba(0, 0, 0, 0) 48%,rgba(0, 0, 0, 0.2) 50%,rgba(0, 0, 0, 0) 52%),-moz-linear-gradient(-45deg,rgba(0, 0, 0, 0) 48%,rgba(0, 0, 0, 0.2) 50%,rgba(0, 0, 0, 0) 52%);
  background: -webkit-linear-gradient(45deg,rgba(0, 0, 0, 0) 48%,rgba(0, 0, 0, 0.2) 50%,rgba(0, 0, 0, 0) 52%),-webkit-linear-gradient(-45deg,rgba(0, 0, 0, 0) 48%,rgba(0, 0, 0, 0.2) 50%,rgba(0, 0, 0, 0) 52%);
  background: -ms-linear-gradient(45deg,rgba(0, 0, 0, 0) 48%,rgba(0, 0, 0, 0.2) 50%,rgba(0, 0, 0, 0) 52%),-ms-linear-gradient(-45deg,rgba(0, 0, 0, 0) 48%,rgba(0, 0, 0, 0.2) 50%,rgba(0, 0, 0, 0) 52%);
  background: linear-gradient(45deg,rgba(0, 0, 0, 0) 48%,rgba(0, 0, 0, 0.2) 50%,rgba(0, 0, 0, 0) 52%),linear-gradient(-45deg,rgba(0, 0, 0, 0) 48%,rgba(0, 0, 0, 0.2) 50%,rgba(0, 0, 0, 0) 52%);
  background-size: 1em 1em;
  background-color: #fff;
}