.favicon-preview {
  width: 72px;
  height: 72px;
  display: grid;
  place-items: center;
  border-radius: 10px;
  background-color: #fff;
  background-image:
    linear-gradient(45deg, #edf2f4 25%, transparent 25%),
    linear-gradient(-45deg, #edf2f4 25%, transparent 25%),
    linear-gradient(45deg, transparent 75%, #edf2f4 75%),
    linear-gradient(-45deg, transparent 75%, #edf2f4 75%);
  background-size: 12px 12px;
  background-position: 0 0, 0 6px, 6px -6px, -6px 0;
}

.favicon-grid a[data-rendering="smooth"] img { image-rendering: auto; }
.favicon-grid a[data-rendering="pixel"] img { image-rendering: pixelated; }