Add a new CSS file `back-form.css` defining a two-column grid layout for the back button and generic form, with the button positioned at (1,1) with 30px margins and z-index 1. Update both `login.html` and `register.html` to include the stylesheet in the head block and wrap the existing `fancy-button` and `generic-form` elements in a `div.back-form` container, replacing the previous standalone button placement.
Insert an empty Jinja2 block named 'head' inside the <head> element of base.html, enabling child templates to inject custom meta tags, styles, or scripts before the closing head tag.
Add six new meta elements to the HTML head in base.html: theme-color set to black,
application-name and description both set to "Snek chat by Molodetz", author set to
"Molodetz", keywords including "snek, chat, molodetz", and color-scheme set to dark.
Also insert a blank line after the title block for improved readability.
Set a default "Snek chat by Molodetz" title in base.html and override it with
"Login - Snek chat by Molodetz" and "Register - Snek chat by Molodetz" in their
respective templates, improving user-facing page identification.