Standardize icon classes

Author: choldgraf

src/sphinx_book_theme/header_buttons/__init__.py

@@ -117,6 +117,7 @@ def add_header_buttons(app, pagename, templatename, context, doctree):
                 "tooltip": translation("Fullscreen mode"),
                 "icon": "fas fa-expand",
                 "label": "fullscreen-button",
+                "classes": "pst-navbar-icon",
             }
         )
 

src/sphinx_book_theme/theme/sphinx_book_theme/components/toggle-secondary-sidebar.html

@@ -1,7 +1,7 @@
 {# The in-page Table of Contents -#}
 {% set page_toc = generate_toc_html() -%}
 {% if page_toc -%}
-<button class="sidebar-toggle secondary-toggle btn btn-sm" title="Toggle secondary sidebar" data-bs-placement="bottom" data-bs-toggle="tooltip">
+<button class="sidebar-toggle secondary-toggle btn btn-sm pst-navbar-icon" title="Toggle secondary sidebar" data-bs-placement="bottom" data-bs-toggle="tooltip">
     <span class="fa-solid fa-list"></span>
 </button>
 {%- endif %}