public StyleDocument Mixin()
{
foreach(var rule in Rules)
{
foreach (var mixin in rule.Mixins)
{
StyleSelector mixin1 = mixin;
var mixinrule = Rules.Find(r => r.Selectors.Exists(s => s.Name == mixin1.Name));
rule.Properties.AddRange(mixinrule.Properties);
}
rule.Mixins.Clear();
}
return this;
}
}