excalidraw/src/components/GitHubCorner.tsx

import oc from "open-color";
import React from "react";

// https://github.com/tholman/github-corners
export const GitHubCorner = React.memo(
  ({ appearance }: { appearance: "light" | "dark" }) => (
    <svg
      xmlns="http://www.w3.org/2000/svg"
      width="40"
      height="40"
      viewBox="0 0 250 250"
      className="github-corner rtl-mirror"
    >
      <a
        href="https://github.com/excalidraw/excalidraw"
        target="_blank"
        rel="noopener noreferrer"
        aria-label="GitHub repository"
      >
        <path
          d="M0 0l115 115h15l12 27 108 108V0z"
          fill={appearance === "light" ? oc.gray[6] : oc.gray[8]}
        />
        <path
          className="octo-arm"
          d="M128 109c-15-9-9-19-9-19 3-7 2-11 2-11-1-7 3-2 3-2 4 5 2 11 2 11-3 10 5 15 9 16"
          style={{ transformOrigin: "130px 106px" }}
          fill={appearance === "light" ? oc.white : oc.black}
        />
        <path
          className="octo-body"
          d="M115 115s4 2 5 0l14-14c3-2 6-3 8-3-8-11-15-24 2-41 5-5 10-7 16-7 1-2 3-7 12-11 0 0 5 3 7 16 4 2 8 5 12 9s7 8 9 12c14 3 17 7 17 7-4 8-9 11-11 11 0 6-2 11-7 16-16 16-30 10-41 2 0 3-1 7-5 11l-12 11c-1 1 1 5 1 5z"
          fill={appearance === "light" ? oc.white : oc.black}
        />
      </a>
    </svg>
  ),
);