v2 proposals

[gucio321]

Hi there.
I've analyzed the code. As far as it works well, some additional features would be appreciated.
Due to the fact that my proposals will (in most cases) be breaking changes, I suggest marking them v2.
Here are some suggestions:

• Rule type rework
  • here is a css reference https://www.w3schools.com/cssref/css_selectors.php
  • Example:
    Suppose we have:

p.foo#bar {...}

This could be parsed to the struct like

type Rule struct {
   Selector string // p
   ID       string // bar
   Class    string // foo
}

Then we can add String() method to easily restore stuff

This struct should be easily expendable

• Because style values could technically be list (like in tests for fontfamily), the field value should also be a list

@napsy what do you think about that?

[gucio321]

also, I think this behaviour is invalid:

func TestParseSelectors(t *testing.T) {
        ex1 := `.rule {
                style1: value1;
                style2: value2;
}
#rule1 sad asd {
        style3: value3;
        style4: value4;
}`

        css, err := Unmarshal([]byte(ex1))
        if err != nil {
                t.Fatal(err)
        }
        if _, ok := css[".rule"]; !ok {
                t.Fatal("Missing '.rule' rule")
        }
        if _, ok := css["#rule1"]; !ok {
                t.Fatal("Missing '.rule' rule")
        }
}

According to this https://www.w3schools.com/cssref/sel_element_element.php "space" is a "descendant" element