How to change syntax highlighting in Jupyter Notebook?

Question

a = np.array([1,4,3]) 
b = np.array([2,-1,5]) 
a@b

df['A'].fillna(value=df['A'].mean())
df.fillna(value=df.mean())

For teaching purposes: I need to apply a special color in Jupyter Notebook for coding to differentiate them from variables:

• a, b: black by default, ok
• 1,4,3: Green by default, ok
• @: Purple by default, ok
• np.array( ): black >>> need to change it to a different color (blue).
• 'A': red by default, ok
• df[ ]: black by default, ok
• .fillna(value=: black >>> need to change it to a different color (blue).
• .mean(): black >>> need to change it to a different color (blue).