Not sure if this question even makes sense, but here goes.
I like some of the features of W3-CSS, particularly Menus.
Would I be better off to start with a Foundation, Boostrap, or maybe Materialize theme?
Also, would you expect conflict problems caused by loading the W3-CSS page?
I'm using SD V3.
Jim

I would go with Materialize.

if I've got you right,
unlike what Twinstream says, the question doesn't really make sense,
and W3.CSS isn't supported by CC, just the three

as is laid out on the description page https://www.w3schools.com/w3css/

W3.CSS is just yet another framework, just like maybe a score of other frameworks, like Bootstrap, Foundation, Materialize, SemanticUI (?), etc etc etc etc ....

develop your own set of html/css classes; or go with a framework to save yourself a lot of work, each has its own set of "strengths", and "shortcomings", depending on the particular task you have in mind (and there are lots of comparison reviews out there)

mixing frameworks is NOT a good idea, but is "theoretically possible", but too much for me, and for most

using templates can help with a lot of things, but using multiple stylesheets -- one developed by a third party for the template -- like a blog page as part of a bigger, overall website, is something discussed here on stackoverflow
https://stackoverflow.com/questions/4284499/use-multiple-css-stylesheets-in-the-same-html-page

is not without problems of its own

Actually if you can open a rsd 1.5 project in sd3 I would have a look at that too....of course top down but only pure coffeegrinder.

One thing that I've noticed is that a lot of people seem to confuse "front-end" (confusing where processing is done on the page vs on the server) for "framework" with how the developer wants the result to look, or what tool the person wants to use to produce a look, with each tool having its strengths and limitations -- "website builders" (like CC) are inherently much less powerful than a truly knowledgeable developer -- the more experience you have with a range of builders, the more you'll be surprised by some of the questions people ask --- you'll be saying to yourself -- "but I can do that easily in the free ...." (name the builder).
but for the less knowledgeable, the builders enable people to do things they might not otherwise EVER get to do.

thanks everybody,
I suspected I might be asking a meaningless question due to ignorance.
What led to it was that I was having trouble making a dropdown nav system that I liked using Bootstrap, so I started surfing around. Finally found one made using W3-CSS, and fell in love with it.
BUT, I really don't want to start doing everything by hand, not with my low level of expertise.
So I will stick to the Bootstrap in SDV3 and do my best.

Again, thanks for the helping comments,

Jim

Hi Jim, I discounted using bootstrap for the same reason not being able to create a menu I liked.
In the end I favoured Foundation. Just a demo, but below is a test link for a menu I made? See if you like that. All done on SD3 using Foundation.
http://phildias.com/master.html
Regards Phil

Hello Phil,
I like the way you made the menu, I have been having a hard time trying to get one to work on one of my sites. I do use FF and am in the process of learning SD-3. if it okay with you I will check the source code of the test menu page you made and hopefully I can try and duplicate it and try to get it to work for me.
Great job looks good.
Ray

Hi Ray, I followed this tutorial below using RSD2 and imported to SD3 deleting some of the row classes. You do have to follow it exactly and make you read the important bottom paragraph. Regards Phil

https://www.coffeecup.com/help/articles/create-a-nested-menu-from-scratch/

Thanks Phil, will try that again have tried doing that previously but never could it to work correctly even with help from so many on the forum. Will start again working on it after I get to know SD3 better. Once again thanks.