<input type="checkbox" aria-label="Open the menu">
input {
  --s: 150px; /* size */
  width: var(--s);
  aspect-ratio: 1;
  padding: calc(var(--s)*.1);
  box-sizing: border-box;
  background:
    radial-gradient(closest-side at 12.5% 25%,#000 96%,#0000) 0 0/80% 40%,
    linear-gradient(#000 50%,#0000 0) top/80% 40% repeat-y;
  
  -webkit-appearance:none;
  -moz-appearance:none;
  appearance:none;
  cursor:pointer;
}
input:checked {
  background: 
    radial-gradient(closest-side at 50% 12.5%,#000 96%,#0000) top /20% 80% repeat-y,
    radial-gradient(closest-side at 12.5% 50%,#000 96%,#0000) left/80% 20% repeat-x,
    conic-gradient(from 90deg at 33% 33%, #0000 90deg, #000 0)
     100% 100%/60% 60% padding-box content-box;
  transform: translateZ(0) rotate(45deg);
}

body {
  min-height: 100vh;
  margin: 0;
  display: grid;
  place-content: center;
}
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