---
layout: default
title: Custom CSS
parent: Customizing
nav_order: 99
permalink: /customizing/custom-css
---

## Custom-CSS

The custom.css file allows you to customize the appearance of Mainsail
without the need of rebuilding it. All you need to do is to place a file
named "custom.css" into the configuration directory ".theme" and define
your css rules in there.

![screenshot](../assets/img/customizing/screenshot-custom-css.png)