How to Optimize Font Size and Content Width to Minimize Blank Space on the Right Side

[zhi-xuan-chen]

Describe the bug
The right side of the website has a large blank area. How can I adjust the font size and content display width to reduce the blank space?

Screenshots

[jakesong15]

I've also had issues with some pages showing the blank space and some pages not showing the blank space, and managed to find a work-around solution for this (YMMV):

For pages where you want to remove the empty space on the right, begin the page files in your _pages directory with layout: archive
For pages where you want to insert the empty space on the right, begin the page files in your _pages directory with layout: single