2nd/10_Wiki/Topics/Topic_Programming/Topic_CSS/CSS_Accessibility.md

id, title, category, status, verification_status, canonical_id, aliases, duplicate_of, source_trust_level, confidence_score, created_at, updated_at, review_reason, merge_history, tags, raw_sources, applied_in, github_commit

id	title	category	status	verification_status	canonical_id	aliases	duplicate_of	source_trust_level	confidence_score	created_at	updated_at	review_reason	merge_history	tags	raw_sources	applied_in	github_commit
css-accessibility	CSS Accessibility	Frontend	draft	conceptual		CSS a11y accessible CSS focus styles color contrast prefers-reduced-motion		B	0.88	2026-06-23	2026-06-23			css web frontend w3schools accessibility a11y focus	https://www.w3schools.com/css/css_accessibility.asp

CSS Accessibility

🎯 한 줄 통찰 (One-line insight)

Accessible CSS rests on a few habits: high color contrast, readable fonts, visible focus indicators, semantic HTML, and respecting user preferences such as reduced motion. [S1]

🧠 핵심 개념 (Core concepts)

• High color contrast — ensure foreground text stands out strongly against the background. [S1]
• Readable typography — use legible font families, adequate font sizes, and generous line height. [S1]
• Visible focus indicators — interactive elements must have a clear visual focus style. [S1]
• Don't hide focus — never remove the focus outline without providing a visible replacement. [S1]
• Semantic HTML — style semantic elements (<nav>, <aside>) rather than generic <div>s. [S1]
• Respect user preferences — honor settings like reduced motion. [S1]

🧩 추출된 패턴 (Extracted patterns)

• Focus-ring pattern — apply a visible outline on :focus for links, buttons, and inputs. [S1]
• Reduced-motion pattern — wrap a global animation/transition kill-switch in a prefers-reduced-motion: reduce media query. [S1]

📖 세부 내용 (Details)

High color contrast. Use a strong contrast between text and background. The good example uses an #ffffff background with #000000 text; the bad example uses an #eeeeee background with #cccccc text (too low contrast). [S1]

Font, size, and line height. Choose readable typography. The good example uses Arial/sans-serif at 1rem with 1.6 line-height; the bad example uses Georgia/serif at 12px, italic, small-caps variant, with 90% line-height. [S1]

Visible focus indicators. Always use the :focus pseudo-class to ensure that interactive elements (like links, buttons, input fields) have a clear visual focus style. [S1]

a:focus, button:focus, input:focus {
  outline: 2px solid orange;
}

Avoid hiding focus. Never use outline: none without replacement styling. Use a visible alternative such as outline: 2px solid orange. [S1]

Semantic HTML with CSS. Style <nav> and <aside> elements (for example with backgrounds) instead of generic <div> tags, so the document remains meaningful to assistive technology. [S1]

Respect user preferences (reduced motion). Honor a user's reduced-motion preference by disabling animations and transitions inside a media query. [S1]

@media (prefers-reduced-motion: reduce) {
  * {
    animation: none !important;
    transition: none !important;
  }
}

(Note: the exact color/font example code boxes for the contrast and typography sections were described but not captured verbatim from the source. — Not found in source.)

🛠️ 적용 사례 (Applied in summary)

The page's applied demonstrations contrast accessible vs inaccessible choices (white-on-black vs grey-on-light-grey; Arial 1rem/1.6 vs Georgia 12px italic), add a visible orange focus outline to links/buttons/inputs, and disable motion for users who request reduced motion. No external project/commit applications found in the source.

💻 코드 패턴 (Code patterns)

Visible focus ring (language: CSS):

a:focus, button:focus, input:focus {
  outline: 2px solid orange;
}

Respect reduced-motion preference (language: CSS):

@media (prefers-reduced-motion: reduce) {
  * {
    animation: none !important;
    transition: none !important;
  }
}

⚖️ 모순 및 업데이트 (Contradictions & updates)

No contradictions found in the source.

✅ 검증 상태 및 신뢰도

• 상태: draft
• 검증 단계: conceptual (실제 적용 사례 발견 시 applied/validated로 승격 가능)
• 출처 신뢰도: B (W3Schools — widely used educational reference, not a primary standards body)
• 신뢰 점수: 0.88
• 중복 검사 결과: 신규 생성 (New discovery)

🔗 지식 그래프 (Knowledge Graph)

• 상위/루트: CSS Tutorial
• 관련 개념: CSS !important, CSS Optimization, CSS Website Layout
• 참조 맥락: Consulted when making a page usable for keyboard users, low-vision users, and people sensitive to motion.

📚 출처 (Sources)

• [S1] W3Schools — CSS Accessibility — https://www.w3schools.com/css/css_accessibility.asp

📝 변경 이력 (Change history)

• 2026-06-23: Initial draft synthesized from the W3Schools "CSS Accessibility" page (Astra wiki-curation, P-Reinforce v3.1 format).