Optional local web fonts for the payment form.

For each font selected in plugin settings, add a matching CSS file here.
Example: for "Kanit" add kanit.css with @font-face rules pointing to local woff2 files.

Supported font slugs match the admin font dropdown (e.g. kanit.css, noto-sans-thai.css, sarabun.css).

If no local CSS file exists for a selected font, the plugin applies the font-family name using system fallbacks only.
