diff --git a/lib/stylesheet/importer.rb b/lib/stylesheet/importer.rb
index f0b2c7b11c9..882ed5c5ebf 100644
--- a/lib/stylesheet/importer.rb
+++ b/lib/stylesheet/importer.rb
@@ -257,7 +257,8 @@ module Stylesheet
     end
 
     def category_css(category)
-      "body.category-#{category.slug}, body.category-#{category.full_slug} { background-image: url(#{upload_cdn_path(category.uploaded_background.url)}) }\n"
+      full_slug = category.full_slug.split("-")[0..-2].join("-")
+      "body.category-#{category.slug}, body.category-#{full_slug} { background-image: url(#{upload_cdn_path(category.uploaded_background.url)}) }\n"
     end
 
     def font_css(font)
diff --git a/spec/components/stylesheet/importer_spec.rb b/spec/components/stylesheet/importer_spec.rb
index e3a6312c98b..23d538a8cc2 100644
--- a/spec/components/stylesheet/importer_spec.rb
+++ b/spec/components/stylesheet/importer_spec.rb
@@ -13,12 +13,13 @@ describe Stylesheet::Importer do
     expect(compile_css("category_backgrounds")).to_not include("background-image")
 
     background = Fabricate(:upload)
-    category = Fabricate(:category, uploaded_background: background)
+    parent_category = Fabricate(:category)
+    category = Fabricate(:category, parent_category_id: parent_category.id, uploaded_background: background)
 
-    expect(compile_css("category_backgrounds")).to include("body.category-#{category.slug},body.category-#{category.full_slug}{background-image:url(#{background.url})}")
+    expect(compile_css("category_backgrounds")).to include("body.category-#{category.slug},body.category-#{parent_category.slug}-#{category.slug}{background-image:url(#{background.url})}")
 
     GlobalSetting.stubs(:cdn_url).returns("//awesome.cdn")
-    expect(compile_css("category_backgrounds")).to include("body.category-#{category.slug},body.category-#{category.full_slug}{background-image:url(//awesome.cdn#{background.url})}")
+    expect(compile_css("category_backgrounds")).to include("body.category-#{category.slug},body.category-#{parent_category.slug}-#{category.slug}{background-image:url(//awesome.cdn#{background.url})}")
   end
 
   it "applies S3 CDN to background category images" do
@@ -32,7 +33,7 @@ describe Stylesheet::Importer do
     background = Fabricate(:upload_s3)
     category = Fabricate(:category, uploaded_background: background)
 
-    expect(compile_css("category_backgrounds")).to include("body.category-#{category.full_slug}{background-image:url(https://s3.cdn/original")
+    expect(compile_css("category_backgrounds")).to include("body.category-#{category.slug}{background-image:url(https://s3.cdn/original")
   end
 
   it "includes font variable" do