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https://www.loom.com/share/183bfb7c3acf42e3af39e066daf975a7
Steps
Scroll to the Chart Colours section
Select Custom Colours instead of Makerble Colours
Click a colour to launch the Choose Colour Popup
Click the arrow to toggle between the different ways to enter colours
RGB
HSL
HEX
Alternatively, use the Colour Picker to select a colour from a document you are using
The other option is to use the slider and pick a colour from the spectrum
You must add a minimum of five colours but you can add additional colours
Press the Add Another Colour button to add additional colours
Press Submit to save your changes