1. https://runjs.app

    RunJS is a modern JavaScript and TypeScript playground, displaying instant results as you type and providing access to Node and browser APIs

  2. https://github.com/dwyl/learn-elm-architecture-in-javascript

    Learn how to build web applications using the Elm ("Model Update View") Architecture in plain JavaScript. if you're getting into react/redux, this'll help you learn that too.

  3. https://www.designbetter.co/design-systems-handbook

    Design Systems Handbook: Learn how you can create your design system and help your team improve product quality while reducing design debt.

  4. http://javascript.info

    The Modern Javascript Tutorial, how its done now. From the basics to advanced topics with simple, but detailed explanations. Main course contains 2 parts which cover JavaScript as a programming language and working with a browser. There are also additional series of thematic articles.

  5. www.buildwithreact.com

    a periodical of tutorials and advanced articles for the react.js library. If youre new to React, this site has a really good interactive tutorial.

  6. https://css-tricks.com/svg-path-syntax-illustrated-guide/

    an illustrated guide to using the SVG path element.

  7. https://checklist.design

    a comprehensive list of UI elements and states to ensure you have the baseline for a satisfying user experience

  8. https://zellwk.com/blog/nunjucks-with-gulp/

    How To Modularize HTML Using Template Engines and Gulp This article walks you through using the template engine Nunjucks and the task runner Gulp to do some modular HTML.

  9. http://animista.net

    On-demand CSS animations. Play around til you get what you want, then export to CSS for your project!

  10. https://learnjavascript.online

    learn Javascript from scratch in an intuitive environment. First 40 lessons free.

  11. https://zellwk.com/blog/rem-vs-em/

    REM vs. EM: a nice explanation on these two units, and how you can use them in building modular components.

  12. http://jigsaw.w3.org/css-validator/

    The W3C CSS Validation Service: check the validity of your CSS (or HTML with CSS).

  13. http://validator.w3.org/

    The W3C Markup Validation Service: check the markup of web docs in HTML, XHTML, SMIL, MathML, etc.

  14. https://css-tricks.com/specifics-on-css-specificity/

    Specificity of css selectors can get confusing. This article explains how it works.

  15. https://zendev.com/ultimate-guide-to-learning-css.html

    This article is intended to be a resource for learning, finding the best resources around to learn each area of CSS. Topics are arranged in an order that makes sense for learning from scratch. So if youre brand new to CSS, you should be able to start at the top and work downwards, gradually increasing your understanding.

  16. https://css-tricks.com/almanac/

    a reference guide to the many features of CSS.

  17. http://learnlayout.com/

    this site teaches the CSS fundamentals that are used in any websites layout.

  18. https://wizardzines.com

    Programming and CLI "zines"

  19. https://www.sitepoint.com/object-oriented-javascript-deep-dive-es6-classes/

    Object-oriented JavaScript: A Deep Dive into ES6 Classes

  20. http://www.pixelmob.co

    royalty-free images from multiple sources, including Unsplash, Pixabay and Pexels.