# Maintainable CSS with visual regression testing and functional CSS

- Institution: CERN
- Department: Developers@CERN Forum
- Speaker: Sebastian Witowski
- Year: 2017
- Language: English
- Source: [CERN](https://videos.cern.ch/record/3014417)
- Licence: [CERN](http://copyright.web.cern.ch)
- Who can watch: Teens profiles and older (sources give no ratings; placed by Invisible Network from the source's own words)

Maintaining CSS is hard. Once your CSS files grows big, they become full of duplicated rules and unused code. What can we do to solve this problem?

In this talk I will describe two concepts that can help us writing maintainable CSS:

* Visual regression tests that can help us refactor our CSS with confidence * Functional CSS - a different way of writing CSS that can help us produce more maintainable code in the long term.

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## Lectures

1. [Maintainable CSS with visual regression testing and functional CSS](https://invisiblenetwork.ai/learn/cern/3014417/9522bd17f20e), 25 min (CERN's player)