Function generate 

pub fn generate<'a>(
    sources: impl IntoIterator<Item = &'a str>,
    config: &Config,
) -> String

Generate the CSS styles needed based on the given sources.

Each source will be scanned in order to extract atomic classes, then CSS will be generated for each class found.

By default, it splits the source by spaces, double quotes, single quotes, backticks and new lines, while ignoring the content inside arbitrary values/variants and variant groups.

This function also removes duplicated selectors and sorts the generated CSS classes based on the order in which they were defined to avoid conflicts.