iOS: Using CGColorRef to use an RGB color to add drop shadow

    //CGColorRef pixelColor = [[UIColor redColor] CGColor];

    // UIColor* color = [UIColor colorWithCGColor:pixelColor];

 
    CGColorRef*  aqua = [UIColor colorWithRed:0.521569 green:0.768627 blue:0.254902 alpha:1] CGColor];            
    layer.masksToBounds = NO;

    layer.shadowRadius = 1.0f;

    layer.shadowOpacity = 0.5f;

    layer.shadowColor = aqua; // (__bridge CGColorRef)([UIColor grayColor]); // use bridge when it's not a CGColorRef type

    layer.shadowOffset = CGSizeMake( 4.0f, 5.0f);

    layer.shouldRasterize = YES;

    layer.borderWidth = 0.8;