1. Our Questions
- How many pre-made themes can I download, how easy are they to install?
- Is theme customization though the U.I. available and easy?
- How to build a theme from scratch?
2. The Theming Story
There are a handful of pre-made themes for Plone, but with the new Diazo based theming engine built into Plone, it fairly easy for someone who knows HTML, CSS and JS to bring in a standard HTML based theme.
Adding a new theme to Plone can be started via the web.
Base themes vs sub themes
As of Fall 2016, there are 124 themes on drupal.org for Drupal 8.
Drupal 8 uses Twig for its default templating system. Twig is a template engine for the PHP programming language. Its syntax originates from Jinja and Django templates. It's an open source product licensed under a BSD License and maintained by Fabien Potencier. The initial version was created by Armin Ronacher. Symfony2 PHP framework comes with a bundled support for Twig as its default template engine.
The templating language looks very familiar to Jinja2 or Django Templates.