Brittle CSS rules

[korny]

Color style rules can conflict, eg. when you have two kinds defining a .content sub-token. The issue appeared in the Lua scanner: #22 (comment)

To fix this, we would need to make the CSS selectors more strict (using the > operator, for example), but this has to be tested and supported by the CSS mini-interpreter in Encoders::HTML::CSS#get_style_for_css_classes.