You can download the pattern or use the CSS3 code below (you can copy the text).
body {
/* CSS3 pattern provided by JonesPatterns.com */
background:
linear-gradient(90deg,transparent 18%, #a63a50 18%, #a63a50 25%, transparent 25%),
conic-gradient(from 45deg, #a63a50 90deg, transparent 90deg),
conic-gradient(from -135deg, #a63a50 90deg, transparent 90deg) 55px 0 #fff;
background-size: 130px 130px;
}