Hi there, 24°! Please do sleep more, but also note, that, firstly, what changes navbar's "height" is the .top-nav-collapse class, and therefore this is where you should apply some funky styling to see it when the page gets scrolled. Secondly, but what is perhaps more important, at least in terms of animation fluency - please note that what changes with the above mentioned CSS class is not actually navbar's "height" property, but its padding-top and padding-down. This is what the transition targets - changing a different property without adding appropriate CSS transition to it shall grant no animating goodies for anyone. Hope what you achieve with this knowledge will reward you with some sweet sleep, longevity and prosperity in the long run. With Best Regards, Kuba

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