About
good-css is a list of modern CSS techniques, written for coding agents to know and reach for, with a live specimen for each one.
The list is one Markdown document. Each entry says when to use a technique, gives the CSS, explains why it works, sets out the rules for using it, and names who it is borrowed from.
This site draws that document as a page and runs every entry in a frame beside it. A specimen uses the entry's own code blocks, verbatim, inside a small fixture, so what you see is what the entry says. Open a specimen in its own tab to test it in another browser or on a phone.
None of the techniques started here. Every entry credits the people it is borrowed from and links to their writing and to the documentation. If a credit is wrong or missing, write to me.
The list is collected and maintained by Vojta Holik. An agent can read the whole list as Markdown and the instructions for agents.