Feature request: Support for Dynamic class names/CSS style management

[zumoshi]

Currently there is no syntax highlighting, error reporting, auto completion, etc for css blocks as described here:

https://templ.guide/syntax-and-usage/css-style-management#dynamic-class-names

package main

css red() {
	background-color: #ff0000; // <-- No color picker on the left of line numbers, the same way it appears if this was in a .css file.
}

templ button(text string, isPrimary bool) {
	<button class={ red() }>{ text }</button>
}