UIView border layer color with shadow animation

gistfile1.m

        CALayer *layer = self.downloadContainerView.layer;
        layer.shadowOffset = CGSizeMake(2, 2);
        layer.shadowColor = [UIColor blackColor].CGColor;
        layer.shadowRadius = 4.0f;
        layer.shadowPath = [[UIBezierPath bezierPathWithRect:layer.bounds] CGPath];

        CABasicAnimation *color = [CABasicAnimation animationWithKeyPath:@"borderColor"];
        color.fromValue = (id)[UIColor redColor].CGColor;
        color.toValue   = (id)[UIColor lightGrayColor].CGColor;
        self.downloadContainerView.layer.borderColor = [UIColor lightGrayColor].CGColor;
        
        CABasicAnimation *shadowOpacity = [CABasicAnimation animationWithKeyPath:@"shadowOpacity"];
        shadowOpacity.fromValue = @0.3;
        shadowOpacity.toValue   = @0;
        self.downloadContainerView.layer.shadowOpacity = 0;

        CAAnimationGroup *both = [CAAnimationGroup animation];
        both.duration   = 1;
        both.animations = @[color, shadowOpacity];
        both.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionLinear];
        
        [self.downloadContainerView.layer addAnimation:both forKey:@"color and shadow"];