2nd/10_Wiki/Topic_CSS/CSS_Table_Borders.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-table-borders	CSS Table Borders	Frontend	draft	conceptual		table borders border-collapse border-spacing CSS tables table styling collapse borders		B	0.89	2026-06-23	2026-06-23			css web frontend w3schools tables borders	https://www.w3schools.com/css/css_table.asp

CSS Table Borders

🎯 한 줄 통찰 (One-line insight)

Adding borders to table, th, and td separately produces double borders by default; border-collapse: collapse merges them into a single border, while border-spacing (only with separate) controls the gap between separated cell borders. [S1]

🧠 핵심 개념 (Core concepts)

• Border shorthand — the CSS border property is a shorthand property for border-width, border-style, and border-color. [S1]
• Double borders by default — because the <table>, <th>, and <td> elements have separate borders, applying borders to all of them yields double borders. [S1]
• Collapsing — the border-collapse property sets whether table borders should collapse into a single border or be separated as in standard HTML. [S1]

🧩 추출된 패턴 (Extracted patterns)

• Single-border table — apply border-collapse: collapse to the table to merge adjacent cell borders. [S1]
• Spaced cells — set border-collapse: separate and use border-spacing to control distance between cell borders. [S1]
• Outer border only — apply the border property only to the <table> element (not to th/td) to draw a border around just the table. [S1]

📖 세부 내용 (Details)

Table Borders — to add borders to a table, use the CSS border property. The CSS border property is a shorthand property for border-width, border-style, and border-color. The example below specifies a black border for <table>, <th>, and <td> elements: [S1]

table, th, td {
  border: 1px solid;
}

A border color can be added in the same shorthand: [S1]

table, th, td {
  border: 1px solid green;
}

Collapse Table Borders — the tables above have double borders. This is because both the <table>, <th>, and <td> elements have separate borders. To remove double borders, use the border-collapse property: [S1]

table {
  border-collapse: collapse;
}

The border-collapse property can have one of the following values: [S1]

Value	Description
separate	Default value. Borders are separated; each cell will display its own borders
collapse	Borders are collapsed into a single border when possible

Border Spacing — the border-spacing property sets the distance between the borders of adjacent cells. This property works only when border-collapse is set to separate: [S1]

table {
  border-collapse: separate;
  border-spacing: 15px;
}

Borders Around the Table Only — if you only want a border around the table, the border property should only be specified for the <table> element: [S1]

table {
  border: 1px solid;
}

Dotted/styled or rounded border examples: "Not found in source" within the borders portion of this page. [S1]

🛠️ 적용 사례 (Applied in summary)

The page's own examples apply borders to table/th/td, collapse them with border-collapse: collapse, add spacing with border-spacing, and draw a border around the table only. No external project/commit applications found in the source.

💻 코드 패턴 (Code patterns)

Single (collapsed) border table (language: CSS):

table, th, td {
  border: 1px solid;
}
table {
  border-collapse: collapse;
}

Spaced separate borders:

table {
  border-collapse: separate;
  border-spacing: 15px;
}

⚖️ 비교 및 선택 기준 (Comparison & decision criteria)

The page contrasts the two border-collapse values. separate (the default) keeps each cell's borders independent and is the only mode in which border-spacing has any effect — choose it when you want visible gaps between cells. collapse merges adjacent borders into a single line — choose it to eliminate the default double-border appearance. The decision is whether spaced, individually-bordered cells or a single clean grid line is desired. [S1]

⚖️ 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: 0.89
• 중복 검사 결과: 신규 생성 (New discovery)

🔗 지식 그래프 (Knowledge Graph)

• 상위/루트: CSS Tutorial
• 관련 개념: CSS Styling Lists, CSS Styling Links, CSS Font Shorthand
• 참조 맥락: Referenced when applying and collapsing borders on HTML tables.

📚 출처 (Sources)

• [S1] W3Schools — CSS Table Borders — https://www.w3schools.com/css/css_table.asp

📝 변경 이력 (Change history)

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