In this post Emmanuel Yusufu explains how to use PostCSS to let you improve your front-end workflow in 2019.
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By, by CSSNext, hello postcss-preset-env
As CSSNext is now deprecated you can use instead the Postcss plugin "PostCSS Preset Env" to lets you use modern CSS in your style sheet.
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Enhance is a web standards-based HTML framework. It’s designed to provide a dependable foundation for building lightweight, flexible, and future-proof web applications.
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Flat, simple, multi-themed, responsive and hackable Color-Picker library. No dependencies, no jQuery. Compatible with all CSS Frameworks e.g. Bootstrap, Materialize. Supports alpha channel, rgba, hsla, hsva and more!