feat: add github corners

Author: Shirajuki

src/partials/head.html

@@ -17,3 +17,60 @@
   </script>
   {{/if}}
 </head>
+<a
+  href="https://github.com/Shirajuki/js-game-rendering-benchmark"
+  class="github-corner"
+  aria-label="View source on GitHub"
+  ><svg
+    width="80"
+    height="80"
+    viewBox="0 0 250 250"
+    style="
+      fill: #151513;
+      color: #fff;
+      position: absolute;
+      top: 0;
+      border: 0;
+      right: 0;
+    "
+    aria-hidden="true"
+  >
+    <path d="M0,0 L115,115 L130,115 L142,142 L250,250 L250,0 Z"></path>
+    <path
+      d="M128.3,109.0 C113.8,99.7 119.0,89.6 119.0,89.6 C122.0,82.7 120.5,78.6 120.5,78.6 C119.2,72.0 123.4,76.3 123.4,76.3 C127.3,80.9 125.5,87.3 125.5,87.3 C122.9,97.6 130.6,101.9 134.4,103.2"
+      fill="currentColor"
+      style="transform-origin: 130px 106px"
+      class="octo-arm"
+    ></path>
+    <path
+      d="M115.0,115.0 C114.9,115.1 118.7,116.5 119.8,115.4 L133.7,101.6 C136.9,99.2 139.9,98.4 142.2,98.6 C133.8,88.0 127.5,74.4 143.8,58.0 C148.5,53.4 154.0,51.2 159.7,51.0 C160.3,49.4 163.2,43.6 171.4,40.1 C171.4,40.1 176.1,42.5 178.8,56.2 C183.1,58.6 187.2,61.8 190.9,65.4 C194.5,69.0 197.7,73.2 200.1,77.6 C213.8,80.2 216.3,84.9 216.3,84.9 C212.7,93.1 206.9,96.0 205.4,96.6 C205.1,102.4 203.0,107.8 198.3,112.5 C181.9,128.9 168.3,122.5 157.7,114.1 C157.9,116.9 156.7,120.9 152.7,124.9 L141.0,136.5 C139.8,137.7 141.6,141.9 141.8,141.8 Z"
+      fill="currentColor"
+      class="octo-body"
+    ></path></svg></a
+><style>
+  .github-corner:hover .octo-arm {
+    animation: octocat-wave 560ms ease-in-out;
+  }
+  @keyframes octocat-wave {
+    0%,
+    100% {
+      transform: rotate(0);
+    }
+    20%,
+    60% {
+      transform: rotate(-25deg);
+    }
+    40%,
+    80% {
+      transform: rotate(10deg);
+    }
+  }
+  @media (max-width: 500px) {
+    .github-corner:hover .octo-arm {
+      animation: none;
+    }
+    .github-corner .octo-arm {
+      animation: octocat-wave 560ms ease-in-out;
+    }
+  }
+</style>