line.css

div {
  background: 
    linear-gradient(45deg, red 25%, transparent 25%),
    linear-gradient(125deg, red 25%, transparent 25%);
}

line.html

div {
  background: linear-gradient(45deg, red 25%, transparent 25%),
    linear-gradient(125deg, red 25%, transparent 25%);
}

r.css

.repeat-radial {
  background: repeating-radial-gradient( circle at bottom left, white, white 10px, red 10px, red 20px);
}