diff --git a/Changelog.md b/Changelog.md
index 4e126ce..ca7e0c4 100644
--- a/Changelog.md
+++ b/Changelog.md
@@ -2,6 +2,8 @@
[full changelog](https://github.com/Mange/roadie/compare/v5.2.0...master)
+* Don't strip the [`:root` pseudo-class](https://developer.mozilla.org/en-US/docs/Web/CSS/:root) - [Asger Behncke Jacobsen](https://github.com/asgerb) (#173)
+
### 5.2.0
[full changelog](https://github.com/Mange/roadie/compare/v5.1.0...v5.2.0)
diff --git a/lib/roadie/selector.rb b/lib/roadie/selector.rb
index 895a98e..7503f20 100644
--- a/lib/roadie/selector.rb
+++ b/lib/roadie/selector.rb
@@ -71,6 +71,7 @@ def ==(other)
:before :after
:enabled :disabled :checked
:host
+ :root
].freeze
def pseudo_element?
diff --git a/spec/integration_spec.rb b/spec/integration_spec.rb
index f2f583f..fc458fe 100644
--- a/spec/integration_spec.rb
+++ b/spec/integration_spec.rb
@@ -67,6 +67,29 @@ def parse_html(html)
expect(styles).to include Roadie::Stylesheet.new("", css).to_s
end
+ it "does not strip :root pseudo-class" do
+ document = Roadie::Document.new <<-HTML
+
+
+ Hello world!
+
+
+ Hello world!
+
+
+ HTML
+ css = <<-CSS
+ :root { --color: red; }
+ CSS
+ document.add_css css
+
+ result = parse_html document.transform
+ expect(result).to have_selector("html > head > style")
+
+ styles = result.at_css("html > head > style").text
+ expect(styles).to include Roadie::Stylesheet.new("", css).to_s
+ end
+
it "can be configured to skip styles that cannot be inlined" do
document = Roadie::Document.new <<-HTML