My suggestion for Guru: increase the font size to something modern, bigger and easier to read across all devices, even if it will continue to be unconfigurable by customers themselves.
This goes especially for the font size in Card View.
You're using 14px font size, whereas modern online publishing and reading tools such as Medium use 21px!
I did some experiments on my local computer for a saved Guru version, and saw that even 19px seem just fine for your font family.
Thank you very much!