html layout: frame width/alignment and font size

I would suggest to update the site settings, namely the width of the main frame and/or font size.
This probably requires wrangling on the Hugo/CSS side.

In desktop computer browsers, tutorials and articles appear shifted to the left side; the frame just covers about half of the screen.
Font size is slightly increased, which leads to the odd situation that there are only 67 characters displayed in code boxes.

I suspect that this is beneficial for mobile compatibility; and large fonts might improve accessibility. However, it is a waste of space on regular computer screens. The font size in code blocks complicates reading code.

For comparison, refer to a plain vanilla quarto html export. I do not think that the main frame is actually that much wider. However, it is centered, and font size is normal. Some websites offer font size adjustment options.

If a general overhaul is required, this might be tackled together with the floating TOC (issue 215).

Start by inspecting the Hugo/CSS site settings that control the main frame, alignment, and code-block font size, then compare the desktop rendering with a plain vanilla Quarto HTML export. Done should mean that tutorials use screen space more effectively on desktop, remain usable on mobile, and make code boxes easier to read.