I'm building my own web site as well as studying Web Development and I have questions for experienced devs.

Firstly I want to add a hamburger menu to my website to click and visit other pages and but not sure how to do it. Found some handy codes and tried to add them to my main HTML and CSS files but it didn't work. Do I need to create whole different HTML/CSS/JS files for the menu and then link them to the main ones? Or what is the solution?

Few examples I can use: https://codepen.io/brenden/pen/VLjKMQ/ https://codepen.io/netfuel/pen/rIlnB/ https://codepen.io/sergioandrade/pen/onkub

My second question is that I added share buttons to my web site through Add To Any. Twitter and WhatsApp buttons work pretty well but Facebook doesn't (see in the first ss). href code is href="https://www.addtoany.com/share" My web site is not online yet. Can that cause an error?

Also I want to make buttons smaller and responsive (see in the second ss). I tried style="font-size: .. ;" so far but didn't work.

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