More website loading speed and code improvements

website/templates/book.html

@@ -5,7 +5,7 @@
 {%- set meta_article_type = true -%}
 {%- set meta_description = page.extra.summary | default(value = page.content | striptags | safe | linebreaksbr | replace(from = "<br>", to = " ") | replace(from = "  ", to = " ") | trim | truncate(length = 200)) -%}
 {%- set linked_css = ["/syntax-highlighting.css"] -%}
-{%- set css = ["/book.css"] -%}
+{%- set css = ["/template/book.css", "/layout/reading-material.css", "/component/code-snippet.css"] -%}
 {%- set js = ["/js/book.js"] -%}
 {%- endblock head -%}