The cake on the tram

Text 1: Four More Stops, by Rupert Haldane

An original novel extract.

The cake had taken Nadia two evenings and most of her savings, and now it sat in a white box on her knees as the number 3 tram lurched out of Market Street. Two tiers, coconut and lime, with her grandmother’s name piped across the top in silver. At the next stop a school party poured on, all elbows and rucksacks. A boy swung round to shout to his friend and his bag skimmed the lid. Nadia hunched over the box like a goalkeeper. The tram braked hard at the lights, and she felt the top tier slide a centimetre towards the corner. Something sticky was already seeping through the cardboard by her thumb. Four more stops, she told herself, and pressed her palms flat against the sides to hold the whole thing still.

Give three words or phrases that show the cake is in danger on the journey.