2nd/10_Wiki/Topic_CSS/CSS_Gradients_Linear.md

---
id: css-linear-gradients
title: "CSS Linear Gradients"
category: "Frontend"
status: "draft"
verification_status: "conceptual"
canonical_id: ""
aliases: ["linear-gradient", "CSS gradients", "repeating-linear-gradient", "gradient background", "CSS color transitions"]
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", "gradients", "linear-gradient", "background-image"]
raw_sources: ["https://www.w3schools.com/css/css3_gradients.asp"]
applied_in: []
github_commit: ""
---

# [[CSS Linear Gradients]]

## 🎯 한 줄 통찰 (One-line insight)
CSS gradients let you display smooth transitions between two or more specified colors; a linear gradient (`linear-gradient()`) runs along a straight line whose direction you set with keywords or an angle, and it is applied through the `background-image` property. [S1]

## 🧠 핵심 개념 (Core concepts)
- **Gradients = smooth color transitions** — CSS gradients display smooth transitions between two or more specified colors. [S1]
- **Three gradient types** — CSS defines linear gradients (going straight in a line), radial gradients (defined by a center point), and conic gradients (rotated around a center point). [S1]
- **Applied via `background-image`** — gradient functions are used as the value of the `background-image` property. [S1]
- **Linear gradient needs ≥ 2 color stops** — you must define at least two color stops; the gradient transitions between them. [S1]
- **Direction is optional** — you can specify a direction (with keywords like `to bottom`/`to right`) or an angle; if omitted, the default is top to bottom. [S1]

## 🧩 추출된 패턴 (Extracted patterns)
- **Direction-keyword pattern** — `linear-gradient(to <direction>, color1, color2)` to flow toward a side or corner. [S1]
- **Angle pattern** — `linear-gradient(<deg>, color1, color2)` for precise gradient angles. [S1]
- **Multi-stop pattern** — list more than two colors to create banded/rainbow transitions. [S1]
- **Transparency pattern** — use `rgba()` colors whose alpha varies to fade a gradient in or out. [S1]
- **Repeating pattern** — `repeating-linear-gradient()` repeats a percentage-defined color sequence. [S1]

## 📖 세부 내용 (Details)
**Syntax** [S1]
```
background-image: linear-gradient(direction, color-stop1, color-stop2, ...);
```
A linear gradient requires at least two color stops, and you may specify a direction or an angle.

**Top to Bottom (this is default)** [S1]
```css
#grad {
  background-image: linear-gradient(to bottom, red, yellow);
}
```

**Bottom to Top** [S1]
```css
#grad {
  background-image: linear-gradient(to top, red, yellow);
}
```

**Left to Right** [S1]
```css
#grad {
  background-image: linear-gradient(to right, red, yellow);
}
```

**Diagonal (top-left to bottom-right)** [S1]
```css
#grad {
  background-image: linear-gradient(to bottom right, red, yellow);
}
```

**Using Angles** [S1]
If you want more control over the direction of the gradient, you can define an angle instead of the predefined directions. The angle is specified as an angle between a horizontal line and the gradient line. Reference values: `0deg` = bottom to top, `90deg` = left to right, `180deg` = top to bottom, `270deg` = right to left.
```css
#grad {
  background-image: linear-gradient(180deg, red, yellow);
}
```

**Using Multiple Color Stops** [S1]
```css
#grad {
  background-image: linear-gradient(red, yellow, green);
}
```
Rainbow example:
```css
#grad {
  background-image: linear-gradient(to right, red, orange, yellow, green, blue, indigo, violet);
}
```

**Using Transparency** [S1]
CSS gradients also support transparency, which can be used to create fading effects. To add transparency, use the `rgba()` function to define the color stops. The last parameter in the `rgba()` function is the alpha value, defining the opacity: 0 indicates full transparency, 1 indicates full color (no transparency).
```css
#grad {
  background-image: linear-gradient(to right, rgba(255,0,0,0), rgba(255,0,0,1));
}
```

**Repeating a linear-gradient** [S1]
The `repeating-linear-gradient()` function is used to repeat linear gradients.
```css
#grad {
  background-image: repeating-linear-gradient(red, yellow 10%, green 20%);
}
```

## 🛠️ 적용 사례 (Applied in summary)
The page's own demonstrations (the `#grad` element styled with each direction, angle, multi-stop, transparency, and repeating example) serve as the applied examples. No external project/commit applications found in the source.

## 💻 코드 패턴 (Code patterns)
Linear gradient with a direction keyword (language: CSS):
```css
#grad {
  background-image: linear-gradient(to right, red, yellow);
}
```
Linear gradient by angle:
```css
#grad {
  background-image: linear-gradient(180deg, red, yellow);
}
```
Repeating linear gradient:
```css
#grad {
  background-image: repeating-linear-gradient(red, yellow 10%, green 20%);
}
```

## ⚖️ 비교 및 선택 기준 (Comparison & decision criteria)
- **Direction keyword vs angle** — keywords (`to bottom`, `to right`, `to bottom right`) cover the common axes and corners; an explicit angle (`0deg`/`90deg`/`180deg`/`270deg`) gives more precise control over the gradient direction. [S1]
- **Single gradient vs repeating** — use `linear-gradient()` for a one-time transition across the box; use `repeating-linear-gradient()` when the percentage-defined color sequence should tile/repeat. [S1]
- **Solid color stops vs `rgba()`** — use `rgba()` color stops when a fading (transparency) effect is desired rather than an opaque transition. [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:** 0.90
- **중복 검사 결과:** 신규 생성 (New discovery)

## 🔗 지식 그래프 (Knowledge Graph)
- **상위/루트:** [[CSS Tutorial]]
- **관련 개념:** [[CSS Radial Gradients]], [[CSS Conic Gradients]], [[CSS Box Shadow]]
- **참조 맥락:** Referenced whenever a smooth, direction-based color background is needed via `background-image`.

## 📚 출처 (Sources)
- [S1] W3Schools — CSS Linear Gradients — https://www.w3schools.com/css/css3_gradients.asp

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