In 2021 appeared a new CSS trick which is called the flexbox gap. This property is borrowed from Grid CSS and is called grid-gap. The gap is used to create space between cells.
Responsive CSS Flexbox Guide and Tutorial: From Basics to Advanced
Nikki Siapno on X: 📌 Frontend Development Fundamentals: CSS
javascript - css columns / flexbox with no gaps between items
css-flexbox] issue with the references for gap-006-*? · Issue
gap CSS-Tricks - CSS-Tricks
CSS gap property vs. margin property - LogRocket Blog
The CSS Flexbox Handbook – Complete Guide with Practical Examples
Chromium lands Flexbox gap, Blog
Calculate the Percentage Width of Flex Items When Using Gap
Minding the gap CSS-Tricks - CSS-Tricks