Missing background color when using variables and @media

[depth42]

Describe the bug
Using a @media rule makes background color disappear in combination with using a CSS variable.

To Reproduce
Paginate the attached file "test.html" with Vivliostyle.

test.html.zip

Expected behavior
The box containing the text "test" should have a green background color. Instead it does not have a background color.

Desktop (please complete the following information):

• macOS 14.4
• Safari 17.4

Additional context

• When I remove the @media rule, the green background is shown.
• When I replace the test variable in the @media rule with a literal color, the green background is shown.
• When opening test.html directly in Safari without pagination, the green background is shown.

[MurakamiShinyu]

@depth42 Thanks for reporting the bug! I will investigate the problem.

[MurakamiShinyu]

Fixed in #1315.

Test: (GitHub Gist: https://gist.github.com/MurakamiShinyu/1d1bdbb88903baf3617b14ad1cd5c09b )

• Before the fix (v2.18.1): https://vivliostyle.github.io/viewer/v2.28.1/#src=https://gist.githack.com/MurakamiShinyu/1d1bdbb88903baf3617b14ad1cd5c09b/raw/issue1313-test.html
• After the fix: https://vivliostyle-git-fix-issue1313-vivliostyle.vercel.app/#src=https://gist.githack.com/MurakamiShinyu/1d1bdbb88903baf3617b14ad1cd5c09b/raw/issue1313-test.html