NSDictionary Obj-C to Swift

Dictionary.swift

// attempt to recreate the dictionary in Swift
var style:[String:NSDictionary] = [
            "$default" : [NSFontAttributeName : UIFont(name: "Raleway", size: 12)],
            "strong" : [NSFontAttributeName : UIFont(name: "Raleway-Bold", size: 12)],
            "h1" : [NSFontAttributeName : UIFont(name: "Raleway-Bold", size: 14)]
        ]
        
// use as an NSDictionary fails at runtime
style._bridgeToObjectiveC() as NSMutableDictionary 

NSDictionary.m

NSDictionary *style = @{
    @"$default" : @{NSFontAttributeName  : [UIFont fontWithName:@"Raleway" size:12]},
    @"strong"   : @{NSFontAttributeName  : [UIFont fontWithName:@"Raleway-Bold" size:12]},
    @"h1"       : @{NSFontAttributeName  : [UIFont fontWithName:@"Raleway-Bold" size:14]}
};