Kilotest: Diagnoses of CSS invalid violation by HTML element 0 on Clean Air Task Force (CATF) donate page

Basics

About the page

• URL: https://give.catf.us/campaign/756949/donate
• Tested 3 days ago on 2026-10-07 at 19:54 by job 261007T1941-qiu
• Summary of results:
  • Rule engines:
    • Called: 12
    • Were able to test: 12
    • Reported any rule violations: 10
  • Violations: 515
  • Violators: 123
  • Issues: 38
• Download the full technical report (JSON)

About the issue

• Why it matters: Page cannot be properly displayed
• Priority: high
• Related WCAG standard: 4.1
• Reported by 1 rule engine (Html Checker API)
• Violations: 2
• Violators: 1

About the violator

• Tag name: HTML
• Text: [not applicable]
• Start tag: <html lang="en">
• XPath: /html
• Bounding box: x = 0, y = 0, width = 1920, height = 1080
• Reported by Html Checker API

Diagnoses

Here is how rule engines diagnose the CSS invalid issue for HTML element 0 of the Clean Air Task Force (CATF) donate page.

1. CSS: width: Invalid type: 100% + (var(--classy-section__padding-inline--mobile) * 2). Extract: e--mobile) * 2));}@supports (c

   Rule engine: Html Checker API (World Wide Web Consortium)

   Rule: CSS: width: Invalid type: 100% + (var(--classy-section__padding-inline--mobile) * 2).

2. CSS: width: Invalid type: 100% + (var(--classy-section__padding-inline--tablet) * 2). Extract: e--tablet) * 2));}}}</style><d

   Rule engine: Html Checker API (World Wide Web Consortium)

   Rule: CSS: width: Invalid type: 100% + (var(--classy-section__padding-inline--tablet) * 2).