The HTML pages of WordPress contain a lot of CSS classes to style them by default. Themes such as JBST 4 can overwrite WordPres's default HTML code and enable you to change the HTML structure of elements of your WordPress website.
You can read more about the WordPress template hierarchy at https://developer.wordpress.org/themes/basics/template-hierarchy/. Let's take the search form as an example. To display a site search form on your website you can call the WordPress
get_search_form() PHP function. This function returns a search form built with the HTML code as shown in the following:
<form role="search" method="get" id="searchform" class="searchform" action="<?php echo esc_url( home_url( ...