html {
  --s: 200px; /* control the size */
  --c: #fff; /* first color */
  
  --_g: #0000 8%,var(--c) 0 17%,#0000 0 58%;
  background: 
    linear-gradient(135deg,#0000 20.5%,var(--c) 0 29.5%,#0000 0) 0 calc(var(--s)/4),
    linear-gradient( 45deg,var(--_g)) calc(var(--s)/2) 0,
    linear-gradient(135deg,var(--_g),var(--c) 0 67%,#0000 0),        
    linear-gradient( 45deg,var(--_g),var(--c) 0 67%,#0000 0 83%,var(--c) 0 92%,#0000 0),
    #1095c1; /* second color */
  background-size: var(--s) var(--s);
}

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