---
id: css-border-style
title: "CSS Border Style"
category: "Frontend"
status: "draft"
verification_status: "conceptual"
canonical_id: ""
aliases: ["border-style", "CSS border style", "border types", "dotted border", "solid border"]
duplicate_of: ""
source_trust_level: "B"
confidence_score: 0.9
created_at: 2026-06-23
updated_at: 2026-06-23
review_reason: ""
merge_history: []
tags: ["css", "web", "frontend", "w3schools", "border", "border-style"]
raw_sources: ["https://www.w3schools.com/css/css_border.asp"]
applied_in: []
github_commit: ""
---

# [[CSS Border Style]]

## 🎯 한 줄 통찰 (One-line insight)
The `border-style` property specifies what kind of border to display and is the gatekeeper of all border styling — none of the other border properties (width, color) have any effect unless `border-style` is set. [S1]

## 🧠 핵심 개념 (Core concepts)
- **CSS border properties** allow you to specify the style, width, and color of an element's border. [S1]
- **`border-style`** specifies what kind of border to display. [S1]
- **`border-style` is required** — none of the other CSS border properties will have any effect unless `border-style` is set. [S1]
- **Per-side values** — the `border-style` property can take from one to four values, applied to the top, right, bottom, and left borders respectively. [S1]

## 🧩 추출된 패턴 (Extracted patterns)
- **Style-first rule** — always declare `border-style` before width/color; the others are inert without it. [S1]
- **One-to-four value shorthand** — a single `border-style` declaration can style all four sides at once (e.g. `dotted dashed solid double`). [S1]

## 📖 세부 내용 (Details)
**Border Style** [S1]
The `border-style` property specifies what kind of border to display.

The following values are allowed: [S1]

| Value | Meaning |
|-------|---------|
| `dotted` | Defines a dotted border |
| `dashed` | Defines a dashed border |
| `solid` | Defines a solid border |
| `double` | Defines a double border |
| `groove` | Defines a 3D grooved border (effect depends on the border-color value) |
| `ridge` | Defines a 3D ridged border (effect depends on the border-color value) |
| `inset` | Defines a 3D inset border (effect depends on the border-color value) |
| `outset` | Defines a 3D outset border (effect depends on the border-color value) |
| `none` | Defines no border |
| `hidden` | Defines a hidden border |

The `border-style` property can have from one to four values (for the top border, right border, bottom border, and the left border). [S1]

**Example** — demonstrating all of the border-style values, including a `mix` class that supplies four values: [S1]
```css
p.dotted {border-style: dotted;}
p.dashed {border-style: dashed;}
p.solid {border-style: solid;}
p.double {border-style: double;}
p.groove {border-style: groove;}
p.ridge {border-style: ridge;}
p.inset {border-style: inset;}
p.outset {border-style: outset;}
p.none {border-style: none;}
p.hidden {border-style: hidden;}
p.mix {border-style: dotted dashed solid double;}
```

**Note:** None of the OTHER CSS border properties (which you will learn more about in the next chapters) will have ANY effect unless the `border-style` property is set! [S1]

## 🛠️ 적용 사례 (Applied in summary)
The example stylesheet above is the page's own applied example: a set of paragraph classes each demonstrating one `border-style` value, plus a `mix` class applying four values at once. No external project/commit applications found in the source.

## 💻 코드 패턴 (Code patterns)
Single value applied to all four sides (language: CSS):
```css
p.solid {border-style: solid;}
```
Four values, one per side (top, right, bottom, left):
```css
p.mix {border-style: dotted dashed solid double;}
```

## ⚖️ 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:** 0.90
- **중복 검사 결과:** 신규 생성 (New discovery)

## 🔗 지식 그래프 (Knowledge Graph)
- **상위/루트:** [[CSS Tutorial]]
- **관련 개념:** [[CSS Border Width]], [[CSS Border Color]], [[CSS Border Sides]], [[CSS Border Shorthand]]
- **참조 맥락:** The mandatory first step for any element border; referenced whenever width or color is applied.

## 📚 출처 (Sources)
- [S1] W3Schools — CSS Border Style — https://www.w3schools.com/css/css_border.asp

## 📝 변경 이력 (Change history)
- 2026-06-23: Initial draft synthesized from the W3Schools "CSS Border Style" page (Astra wiki-curation, P-Reinforce v3.1 format).
