Status
This page documents the implementation status of various HTML and CSS features in Blitz.
This page documents Blitz's scores on the "css" subsuite of the Web Platform Tests.
Note: As it does not have a JavaScript engine, Blitz can only run about 20% of the total subtests. In the numbers below, tests that Blitz can't run are ignored and percentages are relative to the number of tests run.
Data from commit:
1093b86 wpt: skip non-UTF-8 test files instead of crashing (#659) (2026-08-09)
wpt / css / css-backgrounds
| Area | Interop Score | Tests | Test % | Subtests | Subtest % |
|---|---|---|---|---|---|
| Total | 36.50% | (261/714) | 36.55% | (261/714) | 36.55% |
| animations | 41.80% | (18/43) | 41.86% | (18/43) | 41.86% |
| background-attachment-local | 0.00% | (0/17) | 0.00% | (0/17) | 0.00% |
| background-clip | 24.00% | (12/50) | 24.00% | (12/50) | 24.00% |
| background-origin | 41.60% | (5/12) | 41.67% | (5/12) | 41.67% |
| background-position | 66.60% | (2/3) | 66.67% | (2/3) | 66.67% |
| background-repeat | 87.50% | (7/8) | 87.50% | (7/8) | 87.50% |
| background-size | 5.50% | (12/217) | 5.53% | (12/217) | 5.53% |
| box-shadow | 0.00% | (0/7) | 0.00% | (0/7) | 0.00% |
| crashtests | 100.00% | (2/2) | 100.00% | (2/2) | 100.00% |
| hidpi | 0.00% | (0/1) | 0.00% | (0/1) | 0.00% |