Hi @john f102 thanks for posting in the community! Unfortunately if you are using the Mind Map options to set a colour for each level it is not possible have separate colours for different nodes. 

However it is possible to draw a selection box over the nodes in the level you'd like to style and select a colour for them using the colour fill option. If you use this option the colour of these nodes will not change when you update the colours in the 'advanced options' view above. For more information about styling your mind map I recommend taking a look at the Style your mind map section of the Create mind maps in Lucidchart help center article.

That said I can certainly see how the option to have different colours within a level would be helpful when creating complex mind maps. I've gone ahead and logged this feedback with our development team! If there is any additional details you'd like to share regarding this feature request please feel free to comment on this thread and we would be happy to pass this onto the relevant teams.

I hope this helps. Feel free to let us know if you have any questions!