add local TailwindCSS, fix side bar folder view, add more function to Markdown editor and allow .markdown files

README.md

@@ -120,7 +120,12 @@ gobsidian/
 ### Building
 
 To build a standalone binary:
-
+```bash
+# in case you change CSS or add some, recompile tailwind.css
+wget https://github.com/tailwindlabs/tailwindcss/releases/download/v4.1.12/tailwindcss-linux-x64
+chmod +x tailwindcss-linux-x64
+./tailwindcss-linux-x64 -i ./web/static/tailwind.input.css -o ./web/static/tailwind.css --minify
+```
 ```bash
 go mod tidy
 go build -o gobsidian ./cmd