Text size of item name different sizes on different pages

The version of zen cart is v1.5.5 a fresh install which has been working flawlessly for the past few months until today.
I am very familiar with the cart as well as editing pages on my server when needing to.

Today I had been adding some new products and their images. After adding the products I noticed a few of the images were a little hard to see so I thought I would enlarge them via the admin/images/Image - Product Listing Width and Height by doubling them to see how they looked. Changed height to 160 and width to 200. Looked a bit big so I changed it back to the default 80 by 100.
I also haven't placed any new products on the website for a couple of months or done any work or made changes in that time until the last week or so.

So here's the weird part.

The image changed back to the correct size but the product name info text appeared a little bigger than before (but I think it just appeared bigger).
I checked some products that I had placed on the website a few months ago and the text is way bigger than the other page.
The product info (not the description as that is turned off) is large and the headings - Product Image - Item Name - Price are larger on these older product pages as well.

Does the product info generally increase in size when enlarging the image?

I have not changed any code at all and all I did changed was the image size in the admin.

The new products and the text are all fine and have gone back to correct size.

The old product image can be changed bigger or smaller but the text still stays large on these old pages.
I have tried changing the Product Info - Image Width and Height but nothing changes.

Beats me maybe a problem with the install that didn't show up until now.
Any ideas any body.
Thanks,
Chris.

Are you using a responsive template? Did you change the size of your window screen? Did you zoom in or out using your mouse in all of this? (Ie. on a PC holding the control key and moving the scroll wheel on a mouse upward for example will zoom in, I don't know off hand how to do the same with a Macintosh).

Otherwise, changes that you have made to the template CSS could have not appeared until just now/recently by some refresh of the files and depending on what had been changed and how that change interrelates with what has been modified... Ie. sticky web situation, but I think the focus should be on the first paragraph above more so...

No not a responsive template. The template is Avignon. I checked everything I could think off, zooming in and out, deleting cache etc to see if it was just my pc and many other things including the original files but nothing has worked to get it all back to normal.
No, haven't changed any css files at all for quite some time. Made all the changes I wanted to in the first week of installing the fresh zencart and installing the template.
As I said the only thing I had changed was the image size in the admin to a larger size then back again.
The only pages affected are the all the products that I put in first and the pages were all fine at the time and there after. Now there not.
The new product pages are all fine.
As all the pages run from the same css files, how is it possible that pages are appearing differently, because I have no idea, unless there are separate css files that I am unaware of that handle later input.
Although I may check the database to see if anything looks weird in there.
Anyhow thanks for your suggestions, worse comes to worse I will have to try a new install using the backups.
Cheers,
Chris.

a link to your site would make it MUCH easier to diagnose the problem.

the template is a bit old (3 years) and the author no longer includes the demo on his website. while i am not saying it is a template problem, i just wanted to provide some information for you to think about.

best.