Move to custom SSG instead of eleventy.

docs/renderer/util/google-fonts.js

@@ -0,0 +1,45 @@
+import https from 'node:https'
+
+const UA = 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/83.0.4103.61 Safari/537.36'
+
+const isValidURL = url => {
+  return /fonts.googleapis.com/.test(url)
+}
+
+const downloadFont = url => {
+  return new Promise((resolve) => {
+    let rawData = ''
+    https.get(
+      url,
+      {
+        headers: {
+          'user-agent': UA,
+        },
+      },
+      res => {
+        res.on('data', chunk => {
+          rawData += chunk
+        })
+        res.on('end', () => {
+          resolve(rawData.toString('utf8'))
+        })
+      }
+    )
+  })
+}
+
+const createInlineCss = async url => {
+  if (!isValidURL(url)) {
+    throw new Error('Invalid Google Fonts URL')
+  }
+
+  const content = await downloadFont(url)
+
+  return (
+    `<link rel="preconnect" href="https://fonts.gstatic.com">`+
+    `<link data-href="${url}" rel="stylesheet">`+
+    `<style data-href='${url}'>${content}</style>`
+  )
+}
+
+export default createInlineCss