In #6396 we accepted the current syntax for style queries using the basic (property: value) declaration syntax. That's a good start for properties with discreet values - but there are many use-cases where a more powerful syntax is required:

• For number/size values, we might want to support a range syntax? [edit: done in https://github.com/[css-contain-4] Define a range syntax for style container queries #8376]
• For more complex multi-value properties, we might consider something more like the attribute selector syntax?
• For colors, it might be useful to query their luminosity or contrast in some way?

More discussion and use-cases are in #6396, but we resolved to open a new issue for addressing these questions.