When it comes to CSS, everything is a box. It doesn’t matter if it’s a button, an input, a div, a span, etc. At the end of the day, they’re all boxes in the viewport. You can see this pretty easily…
A Look Into: CSS3 Box-sizing - Hongkiat
Box model
box-sizing CSS-Tricks - CSS-Tricks
CSS Box Sizing
CSS, Box Sizing
CSS Box Model, visually explained. : r/webdev
CSS Box Model :: CIS 526 Textbook
The Box Model Explained
Important Interview Question for Web Developer : Box Sizing Border Box in CSS in Dept
CSS Box Model - Coding Ninjas
CSS: Box Model Explained. As any Frontend Developer, UI/UX…, by Andrew Courter
The Box-Sizing Property: Difference between Content and Border
CSS Box Sizing Property (With Examples)