はじめに

<html lang="en">
  <body>
    <main>
      <h1>Welcome</h1>
      <p style="color: #999999; background-color: #ffffff;">This text has low contrast.</p>
      <a href="/details">Click here</a>
    </main>
  </body>
</html>

$ npm install -g @surea11y/cli
$ surea11y scan ./index.html

surea11y scan: file:///path/to/index.html
  engine: @surea11y/core 1.14.1
  pass: 14   fail: 3   cantTell: 2   notApplicable: 126
  occurrences by tier: fail: 3   cantTell: 2
  needs review: likely fail: 0   likely pass: 0   needs a person: 2
FAIL (3 rule(s)):
  contrast-enhanced  (serious, 1 fail occurrence(s))
    - html > body > main > p
      Element has insufficient color contrast (AAA) of 2.85:1 (foreground:
      #999999, background: #ffffff, font size: 16px, font weight: normal).
      Expected contrast ratio of 7:1 (normal text).
      hint: Change the text color, the background color, or both, so the
      contrast ratio reaches at least 7:1.
  contrast-minimum  (serious, 1 fail occurrence(s))
    - html > body > main > p
      Element has insufficient color contrast of 2.85:1 (foreground:
      #999999, background: #ffffff, font size: 16px, font weight: normal).
      Expected contrast ratio of 4.5:1 (normal text).
      hint: Change the text color, the background color, or both, so the
      contrast ratio reaches at least 4.5:1.
  page-title-present  (serious, 1 fail occurrence(s))
    - head > title
      This page has no <title> element.
      hint: Add a <title> that says what the page is about or what it is for.
cantTell — needs human review (2 rule(s)): link-name-quality,
manual-review
criteria (WCAG 2.2):
  fail       1.4.3 Contrast: minimum; 1.4.6 Contrast: enhanced; 2.4.2 Page
             titled
  cantTell   1.1.1 Non-text content: text alternatives; 1.2.1 Audio-only
             and video-only (prerecorded): transcript; 1.2.2 Captions
             (Prerecorded); 1.3.1 Info and Relationships; 1.3.4
             Orientation; 1.3.5 Identify Input Purpose; 1.4.1 Use of
             Color; 1.4.2 Audio Control; 1.4.4 Resize Text; 1.4.5 Images
             of Text; 1.4.12 Text Spacing; 2.1.1 Keyboard; 2.1.3 Keyboard
             (No Exception); 2.2.1 Timing Adjustable; 2.2.2 Pause, Stop,
             Hide; 2.2.4 Interruptions; 2.4.1 Bypass Blocks; 2.4.3 Focus
             order; 2.4.4 Link Purpose (In Context); 2.4.6 Headings and
             Labels; 2.4.7 Focus visible; 2.4.9 Link Purpose (Link Only);
             2.5.8 Target size: minimum; 3.1.1 Language of page; 3.1.2
             Language of Parts; 3.2.5 Change on Request; 3.3.1 Error
             Identification; 3.3.2 Labels or Instructions; 3.3.8
             Accessible Authentication (Minimum); 4.1.2 Name, role, value:
             accessible name; 4.1.2 Name, role, value: ARIA validity;
             4.1.3 Status Messages
  notApplicable: 2
  A criterion that passes here means the checks that ran found nothing in
  it, not that the page conforms.