Refactor css implementation (#6)

Moves CSS from static files in the `public/assets` folder to the asset
pipeline.

Notes:

* I removed the `heroku-deflater` gem due to an asset compilation bug I
encountered on Heroku. The gem has [an open
issue](romanbsd/heroku-deflater#54), but it
doesn't seem worth worrying about right now (I'll likely use Cloudflare
eventually, which will handle the PageSpeed requirement for gzip
compression).

Gemfile

@@ -48,8 +48,6 @@ gem "bootsnap", require: false
 # Use Active Storage variants [https://guides.rubyonrails.org/active_storage_overview.html#transforming-images]
 # gem "image_processing", "~> 1.2"
 
-gem "heroku-deflater", group: :production
-
 group :development, :test do
   # See https://guides.rubyonrails.org/debugging_rails_applications.html#debugging-with-the-debug-gem
   gem "debug", platforms: %i[mri mingw x64_mingw]

Gemfile.lock

@@ -93,8 +93,6 @@ GEM
     erubi (1.12.0)
     globalid (1.2.1)
       activesupport (>= 6.1)
-    heroku-deflater (0.6.3)
-      rack (>= 1.4.5)
     i18n (1.14.1)
       concurrent-ruby (~> 1.0)
     importmap-rails (1.2.1)
@@ -288,7 +286,6 @@ DEPENDENCIES
   bootsnap
   capybara
   debug
-  heroku-deflater
   importmap-rails
   jbuilder
   pg (~> 1.1)

app/assets/stylesheets/theme_1.css

@@ -0,0 +1,15 @@
+/*
+ * This is a manifest file that'll be compiled into application.css, which will include all the files
+ * listed below.
+ *
+ * Any CSS (and SCSS, if configured) file within this directory, lib/assets/stylesheets, or any plugin's
+ * vendor/assets/stylesheets directory can be referenced here using a relative path.
+ *
+ * You're free to add application-wide styles to this file and they'll appear at the bottom of the
+ * compiled file so the styles you add here take precedence over styles defined in any other CSS
+ * files in this directory. Styles in this file should be added after the last require_* statement.
+ * It is generally better to create a new file per style scope.
+ *
+ *= require_tree ../theme_1/stylesheets
+ *= require_self
+ */

app/views/layouts/static.html.erb

@@ -39,15 +39,11 @@
     -->
 
     <!-- Sitewide Stylesheets and Scripts -->
-    <link rel="stylesheet" href="/assets/css/root.css">
-    <link rel="stylesheet" href="/assets/css/dark.css">
+    <%= stylesheet_link_tag "theme_1", "data-turbo-track": "reload" %>
     <script defer src="/assets/js/nav.js"></script>
     <script defer src="/assets/js/dark.js"></script>
 
     <!-- {% block head %}{% endblock %} -->
-    <% if content_for? :for_head %>
-      <%= yield :for_head %>
-    <% end %>
 
     <!--For home page, use service keywords for the title, including location for SEO.
         Other pages should just include the page name.

app/views/static/about.html.erb

@@ -10,10 +10,6 @@ eleventyNavigation:
 ---
 -->
 
-<% content_for :for_head do %>
-    <link rel="stylesheet" href="/assets/css/about.css">
-<% end %>
-
 <!-- {% block body %} -->
     <!-- ============================================ -->
     <!--                    LANDING                   -->

app/views/static/blog.html.erb

@@ -1,7 +1,4 @@
 
-<% content_for :for_head do %>
-    <link rel="stylesheet" href="/assets/css/blog.css">
-<% end %>
   <!-- ============================================ -->
   <!--                    LANDING                   -->
   <!-- ============================================ -->

app/views/static/contact.html.erb

@@ -6,10 +6,6 @@ preloadImg: '/assets/images/cabinets2.jpg'
 permalink: 'contact/'
 ---
 -->
-<% content_for :for_head do %>
-    <link rel="stylesheet" href="/assets/css/contact.css">
-<% end %>
-
     <!-- ============================================ -->
     <!--                    LANDING                   -->
     <!-- ============================================ -->

app/views/static/home.html.erb

@@ -10,11 +10,6 @@ eleventyNavigation:
 ---
 -->
 
-<% content_for :for_head do %>
-    <link rel="stylesheet" href="/assets/css/local.css" />
-    <link rel="stylesheet" href="/assets/css/critical.css" />
-<% end %>
-
 <!-- {% block body %} -->
 
     <!-- ============================================ -->

app/views/static/projects.html.erb

@@ -10,10 +10,6 @@ eleventyNavigation:
 ---
 -->
 
-<% content_for :for_head do %>
-    <link rel="stylesheet" href="/assets/css/projects.css">
-<% end %>
-
     <!-- ============================================ -->
     <!--                    LANDING                   -->
     <!-- ============================================ -->

app/views/static/reviews.html.erb

@@ -10,10 +10,6 @@ eleventyNavigation:
 ---
 -->
 
-<% content_for :for_head do %>
-    <link rel="stylesheet" href="/assets/css/reviews.css">
-<% end %>
-
     <!-- ============================================ -->
     <!--                    LANDING                   -->
     <!-- ============================================ -->