У вашего броузера проблема в совместимости с HTML5
Hey, in this Bootstrap 4 tutorial I'll be going over the basics of the Bootstrap 4 grid system (which is very similar to the original Bootstrap 3 grid). This will prep us for taking a look at some of the added flexbox features in the next lesson.
----- COURSE LINKS:
+ Repo - https://github.com/iamshaunjp/bootstrap-4-playlist
+ Atom editor - https://atom.io/a
+ Download GIT - https://git-scm.com/
+ Bootstrap 4 Docs - https://v4-alpha.getbootstrap.com/getting-started/introduction/
Bootstrap 3 Playlist - https://www.youtube.com/playlist?list=PL4cUxeGkcC9g_69kOfXICzT_hZ79_td99
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========== PSD to WordPress Playlist ==========
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============ Node.js for Beginners Playlist =============
https://www.youtube.com/playlist?list=PL4cUxeGkcC9gcy9lrvMJ75z9maRw4byYp
============== The Net Ninja =====================
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