> For the complete documentation index, see [llms.txt](https://docs.lottielab.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.lottielab.com/editor/properties/fill-color/color-model.md).
# Color model
Color models provide numerical representations of colours so we can easily reference them across systems. Lottielab supports three common models for referencing specific colors, the Hex code, RGB values and HSL.
To change color model and update its value:
* Select a layer with a Fill, and open the color picker
* On the bottom left, click the dropdown (see below) and toggle between color models.
* Enter the value of the color in the input field next to the color model.
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