Change Sidebar width in Quintus

better ask in the theme’s forum at https://www.ads-software.com/support/theme/quintus/

what customisations have you done so far?

it is generally recommended to create a child theme for customisation of the templates, or use a ‘custom CSS’ plugin for changes to the formatting.

ok thank you! I’ve only done color customizations. I’ll try to figure out the jetpack edit css feature.