How to set my webpage to have a perfect size for all devices?

Question

Hello everyone!
I faced another problem today, when I wrote everything in Solo Learn using my phone and the look and size was perfect.
The problem occurred when I tried to use the same codes to see the look of my webpage on my Laptop.
I have to rewrite some codes, and that made me feel bad.
Can someone share something with me to solve the problem??
Even piece of codes and links will mean the world..
..............................Thank You.....................

Answer 1

@Bagshot
hope I will get what I am looking for
Thank you

Answer 2

I already know how to make responsive websites.

Answer 3

@Bagshot
oh! that is it!
let me check

Answer 4

Search code playground for "responsive" and you should find what you're looking for, then study the code. Good luck.

Edit: I found this and it seems to be a great example of responsive design.

https://code.sololearn.com/WToZB17wyNzR/?ref=app

Answer 5

using bootstrap

Answer 6

Include this code in your CSS
.body{width: height:};

Put the size of your device respectively