gap - CSS | MDN
The gap CSS shorthand property sets the gaps (also called gutters) between rows and columns. This property applies to multi-column, flex, and grid containers.| MDN Web Docs
We are an open community of developers, technical writers, and learners building resources for a better Web, regardless of brand, browser, or platform. Anyone can contribute, and each person who does contribute has an impact on millions of readers. Learn how to contribute and drive innovation on the Open Web.| developer.mozilla.org
The gap CSS shorthand property sets the gaps (also called gutters) between rows and columns. This property applies to multi-column, flex, and grid containers.| MDN Web Docs
The :not() CSS pseudo-class represents elements that do not match a list of selectors. Since it prevents specific items from being selected, it is known as the negation pseudo-class.| MDN Web Docs
The border-radius CSS property rounds the corners of an element's outer border edge. You can set a single radius to make circular corners, or two radii to make elliptical corners.| MDN Web Docs
The Popover API provides developers with a standard, consistent, flexible mechanism for displaying popover content on top of other page content. Popover content can be controlled either declaratively using HTML attributes, or via JavaScript.| MDN Web Docs
