fix: validate archive path and use berkeley rose color variable

Agent-Logs-Url: https://github.com/berkeley-cdss/berkeley-class-site/sessions/3cf00aba-dd2e-446c-ba39-1db759bf2bf3

Co-authored-by: cycomachead <1505907+cycomachead@users.noreply.github.com>

Author: Copilot

_config.yml

@@ -44,9 +44,8 @@ logo: /assets/images/berkeley_walking_bear.png
 # This should be one of eecs, dsus, stat
 # (Future) This will control some footer text, and later custom styling.
 course_department: dsus
-# This should be the page of all class archives
-# Typically just / for DS courses (with a visible index page), or /archives if you're hosting your own, or a link to the inst.eecs page
-# If you have no archive page, comment this line out or leave blank.
+# This path/URL is used by the archive banner shown when the site date is outside the semester window.
+# Keep this key present. Default `/` is fine for class-listing homepages, and `/archive` is also a good option.
 # We recommend listing archived offerings as "Archive" or "Not Updated" in course listings.
 class_archive_path: /
 

_plugins/config_validator.rb

@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
 require 'date'
+require 'uri'
 
 # A UC Berkeley-specific validator for Jekyll sites
 # This class validates the following options:
@@ -48,7 +49,8 @@ class ConfigValidator
       course_department: :inclusion_validator,
       color_scheme: :inclusion_validator,
       semester_start_date: :validate_iso8601_date,
-      semester_end_date: :validate_iso8601_date
+      semester_end_date: :validate_iso8601_date,
+      class_archive_path: :validate_archive_path
     }.freeze
 
     attr_accessor :config, :errors
@@ -73,7 +75,7 @@ def validate
     end
 
     def validate_keys!
-      required_keys = %i[baseurl course_department semester_start_date semester_end_date]
+      required_keys = %i[baseurl course_department semester_start_date semester_end_date class_archive_path]
       required_keys.each do |key|
         errors << "#{key} is missing from site config" unless @config.key?(key.to_s)
       end
@@ -117,6 +119,19 @@ def validate_semester_date_range
       errors << '`semester_start_date` must be on or before `semester_end_date`'
     end
 
+    def validate_archive_path(_key, value)
+      path = value.to_s.strip
+      return errors << '`class_archive_path` cannot be blank' if path.empty?
+      return if path.match?(%r{^/})
+
+      uri = URI.parse(path)
+      return if uri.is_a?(URI::HTTP) && uri.host
+
+      errors << "`class_archive_path` must be an absolute path starting with `/` or a full URL, not '#{value}'"
+    rescue URI::InvalidURIError
+      errors << "`class_archive_path` must be an absolute path starting with `/` or a full URL, not '#{value}'"
+    end
+
     def parse_iso8601_date(value)
       Date.iso8601(value.to_s)
     rescue Date::Error

_sass/berkeley/variables.scss

@@ -12,6 +12,7 @@ $serif-font-family: 'Source Serif 4', 'Georiga', 'Baskerville', serif;
 
 $berkeley-blue-old: #003262;
 $berkeley-blue: #002676; // rgb(0, 38, 118);
+$berkeley-rose-medium: #d02670;
 
 // Colors
 $link-color: $berkeley-blue;

_sass/custom/custom.scss

@@ -149,7 +149,7 @@ p.note::before {
   left: 0;
   z-index: 999;
   padding: 0.75rem 1rem;
-  background-color: #d02670;
+  background-color: $berkeley-rose-medium;
   color: #fff;
   font-weight: 700;
   text-align: center;

spec/jekyll/config_validator_spec.rb

@@ -9,7 +9,8 @@
       'baseurl' => '/sp26',
       'course_department' => 'dsus',
       'semester_start_date' => '2026-01-21',
-      'semester_end_date' => '2026-05-09'
+      'semester_end_date' => '2026-05-09',
+      'class_archive_path' => '/'
     }
   end
 
@@ -27,6 +28,25 @@
       .to raise_error(ConfigValidationError, /semester_start_date is missing.*semester_end_date is missing/m)
   end
 
+  it 'requires class_archive_path' do
+    validator = described_class.new(base_config.except('class_archive_path'))
+
+    expect { validator.validate }
+      .to raise_error(ConfigValidationError, /class_archive_path is missing from site config/)
+  end
+
+  it 'allows class_archive_path as a full URL' do
+    validator = described_class.new(base_config.merge('class_archive_path' => 'https://c88c.org/archive'))
+
+    expect { validator.validate }.not_to raise_error
+  end
+
+  it 'rejects class_archive_path values that are not paths or full URLs' do
+    validator = described_class.new(base_config.merge('class_archive_path' => 'archive'))
+    expected = %r{`class_archive_path` must be an absolute path starting with `/` or a full URL}
+    expect { validator.validate }.to raise_error(ConfigValidationError, expected)
+  end
+
   it 'validates ISO-8601 semester dates' do
     validator = described_class.new(base_config.merge('semester_start_date' => 'spring-2026'))