How to develop your own theme for Drupal 8?

Question

CMS

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I want to make a theme for Drupal 8 exactly like here cs.stalker-game.ru/ru/ (copy first, then change everything). I downloaded a theme that was approximately similar in structure, I thought I would edit it (like firebug or in dreamweaver), but I didn’t understand something where it was. Found a bunch of css, php files and that's it. Structures something at all did not understand. Or is it better to develop a theme from scratch? Advise about the development of the theme, please.

Answer 1

Do not make a theme from scratch, it will not end in anything good. Take https://www.drupal.org/project/bootstrap_barrio as an example and edit it.

Answer 2

drupalbook.ru/drupal/8-temizaciya-drupal-8
here is the new version

Answer 3

Go to the Drupal documentation and everything is written there.