What is the best CMS or solution to use for a static gallery?

Question

CMS

Hello.
A situation arose, there is a site with a set of pages on which photographs of works are published, the site itself .
The problem is that there is a lot of work and everything needs to be edited by hand in the html / css code on each page.
I'm tired of this, I want to somehow transfer all this to automation, so that a person who is not familiar with html can add and delete photos from the admin panel.
What is available, a ready-made site with its own design, which must be saved. Pictures are displayed as thumbnails, when clicked, they open in a lightbox.
You need to embed a tool to add images without using html code, ideally CMS. Comments, links to social networks, slideshows, carousels are not needed.
I need advice on what can be done to make this dream come true, given that I only know html / css, a little JS, but I'm not averse to digging, learning the code if necessary.
I was looking at Wordpress + gallery plugins, but did not find adequate options.
I am considering the koken option, but it is not yet clear to me how much it is possible to embed this service into a ready-made website template.
Thank you in advance for your attention and help)

Answer 1

I would advise you to put the site on CMS Wordpress! and get by with the integration of scripts (lightboxes) to pop up images, the rest of the functionality is implemented by the functions of the engine.

Answer 2

Thank you all, let's try it on Wordpress. Even earlier I thought about whether to try Joomla, but as I understand it, the press will be simpler and better suited for this task.
Thanks for the cPortfolio idea, I'll also see what I can do with it.