demo page for basic css 'crt-like' phosphor dot overlay with various shadow mask types and customization
looks best on high-dpi displays at 1080p+
svg masks have a scaling bug in firefox, there will be gaps sometimes
released under cc0 1.0, public domain
/css/phosphor.css and /images/mask can be copied into another project and the overlay elements you want to use (marked with a comment in index.html) can be put anywhere in your HTML, then modify the css based on the styles set using the interactive controls