html {
  --s: 150px; /* control the size */
  --c1: #CCBF82;
  --c2: #604848;
  
  --_g: var(--c1)        6.2%,var(--c2)  6.3% 18.7%,var(--c1) 18.8% 31.2%,
        var(--c2) 31.3% 43.7%,var(--c1) 43.8% 56.2%,var(--c2) 56.3% 68.7%,#0000 68.8%;
  background:
    radial-gradient(var(--s) at 100% 0   ,var(--_g)),
    radial-gradient(var(--s) at 0    0   ,var(--_g)),
    radial-gradient(var(--s) at 0    100%,var(--_g)),
    radial-gradient(var(--s) at 100% 100%,var(--_g)) var(--c1);
  background-size: var(--s) var(--s);
}

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