Drupal 8 Example Page (Inner HTML) template

page.html.twig

    {#
    /**
     * @file
     * Example subtheme implementation to display a single page.
     *
     * The doctype, html, head and body tags are not in this template. Instead they
     * can be found in the html.html.twig template in this directory.
     *
     * Available variables:
     *
     * General utility variables:
     * - base_path: The base URL path of the Drupal installation. Will usually be
     *   "/" unless you have installed Drupal in a sub-directory.
     * - is_front: A flag indicating if the current page is the front page.
     * - logged_in: A flag indicating if the user is registered and signed in.
     * - is_admin: A flag indicating if the user has permission to access
     *   administration pages.
     *
     * Site identity:
     * - front_page: The URL of the front page. Use this instead of base_path when
     *   linking to the front page. This includes the language domain or prefix.
     *
     * Page content (in order of occurrence in the default page.html.twig):
     * - messages: Status and error messages. Should be displayed prominently.
     * - node: Fully loaded node, if there is an automatically-loaded node
     *   associated with the page and the node ID is the second argument in the
     *   page's path (e.g. node/12345 and node/12345/revisions, but not
     *   comment/reply/12345).
     *
     * Regions:
     * - page.header: Items for the header region.
     * - page.primary_menu: Items for the primary menu region.
     * - page.secondary_menu: Items for the secondary menu region.
     * - page.highlighted: Items for the highlighted content region.
     * - page.help: Dynamic help text, mostly for admin pages.
     * - page.content: The main content of the current page.
     * - page.sidebar_first: Items for the first sidebar.
     * - page.sidebar_second: Items for the second sidebar.
     * - page.footer: Items for the footer region.
     * - page.breadcrumb: Items for the breadcrumb region.
     *
     * @see template_preprocess_page()
     * @see html.html.twig
     *
     * @ingroup themeable
     */
    #}


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