Creating Dark Mode Button

[nshah1729]

Prerequisites

• I have searched for duplicate or closed feature requests
• I have read the contributing guidelines

Proposal

Creating a Dark mode button applicable to all pages

Motivation and context

As a user, I always use Dark mode for navigating websites

[sambhavsaxena]

@nshah1729 Its easy to implement dark mode by a toggle button, which will switch the classes on bootstrap from 'light' or 'danger' or anything else to say 'dark', why need an integrated function for that?