How to Change Your Jupyter Notebook Theme

To change or modify your Jupyter Notebook default theme(from the white to your custom theme).You will need to make changes to your custom.css  file located in .jupyter/custom directory. But in most cases there will be no custom directory or folder ,hence you have to create one.
To Locate the folder .jupyter

•  Search for run in windows  or
• type .jupyter  in your terminal in unix based systems.(MacOs,Linux

Create a new folder or directory and rename it as custom

• mkdir custom

Navigate into the folder custom and paste your themes or css styles.

You can get some themes from Github(click here)
Rename your theme as custom.css (Very important)
Start Jupyter notebook with jupyter notebook

NB

You will have to comment out this div#maintoolbar {display: none !important;} to be able to see your main tool bar with the icons

Check the Video