---
id: 5d822fd413a79914d39e9923
title: Part 91
challengeType: 0
isBeta: true
---
## Description
Remove the `background-color` property and value from `fb3` and add them to `fb3a` and `fb3b`.
## Instructions
## Tests
```yml
tests:
- text: test-text
testString: const fb3 = code.match(/\.fb3\s*{[\s\S]+?[^}]}/g)[0]; const fb3a = code.match(/\.fb3a\s*{[\s\S]+?[^}]}/g)[0];const fb3b = code.match(/\.fb3b\s*{[\s\S]+?[^}]}/g)[0]; assert(!/background-color/g.test(fb3) && /background-color\s*:\s*var\(\s*--building-color1\s*\)\s*(;|})/g.test(fb3a) && /background-color\s*:\s*var\(\s*--building-color1\s*\)\s*(;|})/g.test(fb3b));
```
## Challenge Seed
```html
freeCodeCamp Skyline Project
```