syntax higlighting

package.json

@@ -39,6 +39,7 @@
     "preact-render-to-string": "^6.0.3",
     "pretty-time": "^1.1.0",
     "rehype-katex": "^6.0.3",
+    "rehype-pretty-code": "^0.9.6",
     "rehype-raw": "^6.1.1",
     "remark": "^14.0.2",
     "remark-frontmatter": "^4.0.1",
@@ -50,6 +51,7 @@
     "require-from-string": "^2.0.2",
     "rimraf": "^5.0.1",
     "serve-handler": "^6.1.5",
+    "shiki": "^0.14.2",
     "to-vfile": "^7.2.4",
     "unified": "^10.1.2",
     "unist-util-visit": "^4.1.2",