---
id: 5d822fd413a79914d39e98fd
title: Part 53
challengeType: 0
---
## Description
In the next few steps, you are going to use some tricks with CSS borders to turn the `bb2a` section into a triangle at the top of the building. First, remove the `background-color` from `bb2` since you don't need it anymore.
## Instructions
## Tests
```yml
tests:
- text: test-text
testString: const bb2 = code.match(/\.bb2\s*{[\s\S]+?[^}]}/g)[0]; assert(!/background-color/g.test(bb2));
```
## Challenge Seed
```html
freeCodeCamp Skyline Project
```