Add root route

app/Main.hs

@@ -62,7 +62,7 @@ app :: Application
 app = serve (Proxy :: Proxy API) server
 
 type API =
-  Header "Host" Text :> Get '[PlainText] RootModel
+  Header "Host" Text :> Get '[PlainText, HTML] RootModel
   :<|> "utf8" :> Capture "bytes" Text :> Get '[PlainText, HTML] Utf8Model
   :<|> "codepoints" :> Capture "codepoints" Text :> Get '[PlainText, HTML] CodepointsModel
   :<|> "text" :> Capture "text" Text :> Get '[PlainText, HTML] TextModel
@@ -102,13 +102,21 @@ instance MimeRender PlainText RootModel where
   mimeRender _ model = renderText $ Text.unlines $
     [ "⚞ utoy ⚟"
     , ""
-    , "This is utoy, a URL-based Unicode playground. You can try these paths:"
+    , "This is utoy, a URL-based Unicode playground. Examples:"
     , ""
     ] ++ map (urlBase <>) examples
     where
       -- We assume HTTPS here. Doesn't work for development on localhost.
       urlBase = "https://" <> model.host
 
+instance MimeRender HTML RootModel where
+  mimeRender _ model = renderHtml $ documentWithBody $ do
+    H.h1 $ H.toHtml ("⚞ utoy ⚟" :: Text)
+    H.p $ H.toHtml ("This is utoy, a URL-based Unicode playground. Examples:" :: Text)
+    H.ul $ for_ examples $ \example -> do
+      let url = "https://" <> model.host <> example
+      H.li $ H.a ! A.href (H.toValue url) $ H.toHtml example
+
 -- /bytes/<bytes>
 
 newtype Utf8Model = Utf8Model
@@ -270,7 +278,7 @@ documentWithBody body =
       H.meta ! A.charset "utf-8"
       H.title "utoy"
       H.style $ H.toHtml $ Encoding.decodeUtf8 $(embedFile "static/utoy.css")
-    H.body body
+    H.body $ H.main body
 
 -- HTML routes