it works

this plugin make a css file in (plugin) directory. but plugin is necessary in any way… only if wordpress make a function inside admin panel is possible to replace plugin with custom css code without plugin. otherwise, if u make a simple file with code via ftp, u neet to edit theme manually or to make a plugin to insert code in header and include css file. with this small plugin u have color syntax, css file and no theme edit require (no ftp, never)!
i think, is a good plugin (not simply, another plugin).

Agreed, @darkwoof. No FTP needed. No hacking/customizations needed to force WP to look for the new CSS file. No worries about overwrites by theme updates.

Yes. It’s “another plugin”, but like many other plugs, it’s all about making life easier.