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.
Data from commit:
e42ee1f Fix off-screen culling bounds applying node location twice (#1342) (2026-10-30)
| Area | Interop Score | Tests | Test % | Subtests | Subtest % |
|---|---|---|---|---|---|
| Total | 54.10% | (18610/35608) | 52.26% | (118868/223315) | 53.22% |
| css-grid | 55.59% | (1389/2572) | 54.00% | (13731/17681) | 77.65% |
| css-anchor-position | 16.55% | (74/547) | 13.52% | (1933/13944) | 13.86% |
| css-typed-om | 4.04% | (15/411) | 3.64% | (60/13485) | 0.44% |
| css-color | 89.67% | (323/380) | 85.00% | (11623/13045) | 89.09% |
| css-values | 64.44% | (303/521) | 58.15% | (5786/10629) | 54.43% |
| css-fonts | 55.85% | (286/568) | 50.35% | (6636/9061) | 73.23% |
| CSS2 | 73.86% | (4714/6393) | 73.73% | (6954/8868) | 78.41% |
| css-shapes | 17.56% | (67/391) | 17.13% | (718/7771) | 9.23% |
| css-text | 71.43% | (1407/1994) | 70.56% | (4682/7349) | 63.70% |
| css-backgrounds | 70.93% | (595/879) | 67.69% | (5131/6983) | 73.47% |
| css-sizing | 56.25% | (428/824) | 51.94% | (4324/6940) | 62.30% |
| css-masking | 42.19% | (227/571) | 39.75% | (3747/6906) | 54.25% |
| selectors | 52.44% | (419/836) | 50.11% | (2505/6601) | 37.94% |
| css-transforms | 55.83% | (498/934) | 53.31% | (4161/6342) | 65.61% |
| css-flexbox | 86.95% | (1208/1430) | 84.47% | (5190/5835) | 88.94% |
| css-align | 83.93% | (231/304) | 75.98% | (4948/5495) | 90.04% |
| motion | 17.57% | (14/148) | 9.45% | (2475/5061) | 48.90% |
| css-gaps | 10.30% | (64/641) | 9.98% | (383/4721) | 8.11% |
| cssom | 52.32% | (129/303) | 42.57% | (3448/4488) | 76.82% |
| css-images | 40.90% | (206/523) | 39.38% | (3557/4076) | 87.26% |
| css-conditional | 44.16% | (198/468) | 42.30% | (1870/3494) | 53.52% |
| css-transitions | 42.18% | (53/144) | 36.80% | (925/3456) | 26.76% |
| css-ui | 89.06% | (950/1086) | 87.47% | (2697/3432) | 78.58% |
| filter-effects | 46.31% | (187/428) | 43.69% | (1763/3397) | 51.89% |
| cssom-view | 36.15% | (76/250) | 30.39% | (1479/2653) | 55.74% |
| css-multicol | 42.70% | (304/724) | 41.98% | (889/2246) | 39.58% |
| css-break | 21.06% | (273/1310) | 20.83% | (320/1979) | 16.16% |
| css-overflow | 30.57% | (277/940) | 29.46% | (677/1927) | 35.13% |
| css-borders | 53.87% | (165/312) | 52.88% | (1115/1829) | 60.96% |
| mediaqueries | 51.57% | (49/95) | 51.57% | (49/1827) | 2.68% |
| css-cascade | 57.74% | (87/164) | 53.04% | (786/1816) | 43.28% |
| css-view-transitions | 9.93% | (52/528) | 9.84% | (126/1801) | 6.99% |
| css-position | 50.53% | (186/394) | 47.20% | (1149/1787) | 64.29% |
| css-text-decor | 38.84% | (141/374) | 37.70% | (1123/1702) | 65.98% |
| css-writing-modes | 40.87% | (511/1257) | 40.65% | (691/1591) | 43.43% |
| geometry | 87.04% | (26/31) | 83.87% | (1089/1575) | 69.14% |
| css-animations | 54.96% | (109/210) | 51.90% | (831/1512) | 54.96% |
| css-logical | 84.50% | (64/92) | 69.56% | (1265/1454) | 87.00% |
| css-properties-values-api | 33.67% | (35/125) | 28.00% | (536/1407) | 38.09% |
| css-inline | 25.55% | (100/436) | 22.93% | (455/1234) | 36.87% |
| css-lists | 49.04% | (111/236) | 47.03% | (812/1171) | 69.34% |
| css-pseudo | 35.45% | (126/362) | 34.80% | (193/1166) | 16.55% |
| css-tables | 57.73% | (181/353) | 51.27% | (597/1157) | 51.59% |
| css-box | 31.64% | (33/151) | 21.85% | (704/1135) | 62.02% |
| css-contain | 53.93% | (313/593) | 52.78% | (465/993) | 46.82% |
| css-viewport | 70.04% | (99/145) | 68.27% | (314/903) | 34.77% |
| css-scroll-snap | 8.70% | (16/216) | 7.40% | (156/873) | 17.86% |
| css-display | 42.60% | (109/265) | 41.13% | (366/828) | 44.20% |
| css-variables | 89.37% | (214/250) | 85.60% | (600/771) | 77.82% |
| css-mixins | 9.46% | (1/57) | 1.75% | (66/618) | 10.67% |
| css-shadow | 7.05% | (14/208) | 6.73% | (24/494) | 4.85% |
| css-syntax | 59.53% | (28/52) | 53.84% | (414/448) | 92.41% |
| css-counter-styles | 8.17% | (17/271) | 6.27% | (83/417) | 19.90% |
| css-page | 41.73% | (109/263) | 41.44% | (122/413) | 29.53% |
| fill-stroke | 22.15% | (2/11) | 18.18% | (94/410) | 22.92% |
| css-content | 20.20% | (15/80) | 18.75% | (248/324) | 76.54% |
| WOFF2 | 98.32% | (293/298) | 98.32% | (293/298) | 98.32% |
| css-highlight-api | 11.36% | (15/135) | 11.11% | (23/291) | 7.90% |
| css-font-loading | 23.79% | (8/34) | 23.52% | (21/251) | 8.36% |
| css-ruby | 35.75% | (64/179) | 35.75% | (92/248) | 37.09% |
| compositing | 56.58% | (45/81) | 55.55% | (177/233) | 75.96% |
| css-will-change | 60.37% | (32/53) | 60.37% | (200/221) | 90.49% |
| css-size-adjust | 20.00% | (1/5) | 20.00% | (4/215) | 1.86% |
| css-rhythm | 25.50% | (8/35) | 22.85% | (71/201) | 35.32% |
| css-color-adjust | 41.56% | (15/41) | 36.58% | (137/197) | 69.54% |
| css-easing | 75.22% | (9/15) | 60.00% | (127/169) | 75.14% |
| css-layout-api | 13.76% | (20/153) | 13.07% | (24/159) | 15.09% |
| css-nesting | 78.90% | (34/47) | 72.34% | (120/149) | 80.53% |
| css-paint-api | 81.31% | (95/118) | 80.50% | (114/144) | 79.16% |
| css-color-hdr | 14.65% | (0/4) | 0.00% | (17/116) | 14.65% |
| css-scrollbars | 44.44% | (22/57) | 38.59% | (68/115) | 59.13% |
| css-forms | 7.69% | (2/26) | 7.69% | (2/110) | 1.81% |
| css-overscroll-behavior | 41.66% | (5/12) | 41.66% | (82/109) | 75.22% |
| css-scroll-anchoring | 8.13% | (7/86) | 8.13% | (8/107) | 7.47% |
| css-link-params | 17.76% | (1/9) | 11.11% | (17/98) | 17.34% |
| css-navigation | 25.49% | (4/26) | 15.38% | (30/88) | 34.09% |
| css-parser-api | 7.00% | (0/1) | 0.00% | (5/71) | 7.04% |
| css-env | 94.62% | (9/11) | 81.81% | (48/53) | 90.56% |
| printing | 82.05% | (32/39) | 82.05% | (32/39) | 82.05% |
| css-image-animation | 65.21% | (15/23) | 65.21% | (15/27) | 55.55% |
| css-namespaces | 100.00% | (23/23) | 100.00% | (23/23) | 100.00% |
| css-style-attr | 93.75% | (15/16) | 93.75% | (15/16) | 93.75% |
| css-exclusions | 0.00% | (0/12) | 0.00% | (0/15) | 0.00% |
| css-forced-color-adjust | 83.30% | (2/4) | 50.00% | (12/14) | 85.71% |
| css-device-adapt | 28.57% | (2/7) | 28.57% | (2/7) | 28.57% |
| fetching | 0.00% | (0/1) | 0.00% | (0/4) | 0.00% |
| reference | 66.66% | (2/3) | 66.66% | (2/3) | 66.66% |
| css-motion-path | 100.00% | (1/1) | 100.00% | (1/1) | 100.00% |
| css-painting | 0.00% | (0/1) | 0.00% | (0/1) | 0.00% |
| css-zoom | 100.00% | (1/1) | 100.00% | (1/1) | 100.00% |