2nd/10_Wiki/Dev/Topic_CSS/CSS_Pseudo_Elements.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-pseudo-elements	CSS Pseudo-elements	Frontend	draft	conceptual		pseudo-elements ::before ::after ::first-line ::marker double-colon selectors		B	0.88	2026-06-23	2026-06-23			css web frontend w3schools pseudo-elements selectors	https://www.w3schools.com/css/css_pseudo_elements.asp

CSS Pseudo-elements

🎯 한 줄 통찰 (One-line insight)

A CSS pseudo-element is a keyword added to a selector that lets you style a specific part of an element — the first line, the first letter, inserted content, list markers, selected text, or a dialog backdrop. [S1]

🧠 핵심 개념 (Core concepts)

• Definition — A CSS pseudo-element is a keyword that can be added to a selector, to style a specific part of an element. [S1]
• Double-colon syntax — pseudo-elements are written with :: after the selector. [S1]
• Two families — text pseudo-elements (::first-line, ::first-letter) and content pseudo-elements (::before, ::after, ::marker, ::selection, ::backdrop). [S1]

🧩 추출된 패턴 (Extracted patterns)

• Style a part, not the whole — pseudo-elements address sub-parts of an element (a line, a letter, generated content) rather than the element as a whole. [S1]
• Syntax pattern — selector::pseudo-element-name { CSS properties }. [S1]

📖 세부 내용 (Details)

Definition [S1] A CSS pseudo-element is a keyword that can be added to a selector, to style a specific part of an element. Common uses include:

• Styling the first letter or first line of an element
• Inserting content before or after an element
• Styling list item markers
• Styling user-selected portions of an element
• Styling the viewbox behind a dialog box

Syntax [S1]

selector::pseudo-element-name {
  CSS properties
}

Text pseudo-elements [S1]

Pseudo-element	Description
::first-line	Style the first line of text
::first-letter	Style the first letter of text

Content pseudo-elements [S1]

Pseudo-element	Description
::before	Insert content before an element
::after	Insert content after an element
::marker	Style list item markers
::selection	Style user-selected text
::backdrop	Style dialog backdrop

The source references a complete CSS Pseudo-elements Reference for the full list. [S1]

🛠️ 적용 사례 (Applied in summary)

This page is an overview/index; the detailed applied examples live on the dedicated text and content pseudo-element pages. No external project/commit applications found in the source.

💻 코드 패턴 (Code patterns)

Pseudo-element syntax (language: CSS):

selector::pseudo-element-name {
  CSS properties
}

⚖️ 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 Text Pseudo-elements, CSS Content Pseudo-elements, CSS Structural Pseudo-classes
• 참조 맥락: The entry point whenever styling a specific part of an element rather than the whole.

📚 출처 (Sources)

• [S1] W3Schools — CSS Pseudo-elements — https://www.w3schools.com/css/css_pseudo_elements.asp

📝 변경 이력 (Change history)

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