docs(10_Wiki): W3Schools 위키화 — HTML/CSS/JavaScript(core)
W3Schools 튜토리얼을 P-Reinforce v3.1 포맷으로 위키화(영어 본문, 한/영 섹션 헤더). - Topic_HTML: 59문서 (튜토리얼+예제, 레퍼런스/메타 제외) - Topic_CSS: 190문서 (메인 + Advanced/Flexbox/Grid/RWD 전체) - Topic_JavaScript: 120문서 (코어 언어; Temporal/DOM상세/BOM/WebAPI/AJAX/jQuery/Graphics 등은 후속) 각 폴더 00_INDEX.md(MOC) 포함. 코드 verbatim, 미확인분은 "Not found in source" 표기. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
This commit is contained in:
@@ -0,0 +1,170 @@
|
||||
---
|
||||
id: css-dropdowns
|
||||
title: "CSS Dropdowns"
|
||||
category: "Frontend"
|
||||
status: "draft"
|
||||
verification_status: "conceptual"
|
||||
canonical_id: ""
|
||||
aliases: ["dropdown", "CSS dropdown menu", "hover dropdown", "dropdown box", "pure CSS dropdown"]
|
||||
duplicate_of: ""
|
||||
source_trust_level: "B"
|
||||
confidence_score: 0.89
|
||||
created_at: 2026-06-23
|
||||
updated_at: 2026-06-23
|
||||
review_reason: ""
|
||||
merge_history: []
|
||||
tags: ["css", "web", "frontend", "w3schools", "dropdown", "hover", "menu"]
|
||||
raw_sources: ["https://www.w3schools.com/css/css_dropdowns.asp"]
|
||||
applied_in: []
|
||||
github_commit: ""
|
||||
---
|
||||
|
||||
# [[CSS Dropdowns]]
|
||||
|
||||
## 🎯 한 줄 통찰 (One-line insight)
|
||||
A CSS dropdown reveals hidden content on hover by combining a `position: relative` wrapper, an absolutely positioned `display: none` content box, and a `:hover` rule that flips it to `display: block` — no JavaScript required. [S1]
|
||||
|
||||
## 🧠 핵심 개념 (Core concepts)
|
||||
- **Dropdown** — a UI element that displays content (text, links, images) when the user moves over or interacts with a trigger element such as a `div`, `button`, `p`, or `a`. [S1]
|
||||
- **Wrapper positioning** — the outer `.dropdown` container is given `position: relative` so the dropdown content can be positioned relative to it. [S1]
|
||||
- **Hidden-by-default content** — `.dropdown-content` starts at `display: none` and `position: absolute`, so it does not occupy space until shown. [S1]
|
||||
- **Hover reveal** — the `.dropdown:hover .dropdown-content` rule sets `display: block`, exposing the content while the pointer is over the wrapper. [S1]
|
||||
- **Visual depth** — a `box-shadow` is used to give the dropdown box a floating, layered appearance. [S1]
|
||||
|
||||
## 🧩 추출된 패턴 (Extracted patterns)
|
||||
- **Relative-parent / absolute-child** — pair a `position: relative` wrapper with a `position: absolute` content box so the box anchors to the wrapper. [S1]
|
||||
- **Hover toggle** — switch a child from `display: none` to `display: block` via a parent `:hover` descendant selector, achieving show/hide without scripting. [S1]
|
||||
- **Styled trigger button** — a `.dropbtn` class styles the trigger (background color, padding, no border, pointer cursor) and changes color on parent hover. [S1]
|
||||
|
||||
## 📖 세부 내용 (Details)
|
||||
**What is a CSS dropdown?**
|
||||
A CSS dropdown is a UI element that displays content when users click or hover over a trigger element like a button or link. The trigger can be a `div`, `button`, `p`, or `a` tag, and the hidden dropdown content displays on interaction. [S1]
|
||||
|
||||
**Example 1 — Dropdown Box with Text**
|
||||
A basic hoverable dropdown. The parent uses `position: relative`; the `.dropdown-content` is hidden (`display: none`) and absolutely positioned, with a `min-width` of `130px` and a `box-shadow` for depth. The `:hover` selector reveals it: [S1]
|
||||
```html
|
||||
<style>
|
||||
.dropdown {
|
||||
position: relative;
|
||||
}
|
||||
|
||||
.dropdown-content {
|
||||
display: none;
|
||||
position: absolute;
|
||||
background-color: #f9f9f9;
|
||||
min-width: 130px;
|
||||
box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
|
||||
padding: 12px 16px;
|
||||
}
|
||||
|
||||
.dropdown:hover .dropdown-content {
|
||||
display: block;
|
||||
}
|
||||
</style>
|
||||
|
||||
<div class="dropdown">Mouse over me!
|
||||
<div class="dropdown-content">Hello World!</div>
|
||||
</div>
|
||||
```
|
||||
|
||||
**Example 2 — Dropdown Menu**
|
||||
Extends the dropdown into an interactive menu. A styled `.dropbtn` button (green `#4CAF50` background, white text, `16px` padding) triggers the menu; links inside `.dropdown-content` are block-level with padding and no underline, and change background on hover. The button darkens (`#3e8e41`) when the dropdown is hovered: [S1]
|
||||
```html
|
||||
<style>
|
||||
.dropdown {
|
||||
position: relative;
|
||||
}
|
||||
|
||||
/* Style the dropdown button */
|
||||
.dropbtn {
|
||||
background-color: #4CAF50;
|
||||
color: white;
|
||||
padding: 16px;
|
||||
font-size: 16px;
|
||||
border: none;
|
||||
cursor: pointer;
|
||||
}
|
||||
|
||||
/* Dropdown content */
|
||||
.dropdown-content {
|
||||
display: none;
|
||||
position: absolute;
|
||||
background-color: #f9f9f9;
|
||||
min-width: 200px;
|
||||
box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
|
||||
}
|
||||
|
||||
/* Links inside dropdown content */
|
||||
.dropdown-content a {
|
||||
color: black;
|
||||
padding: 12px 16px;
|
||||
text-decoration: none;
|
||||
display: block;
|
||||
}
|
||||
|
||||
/* Change color of dropdown links on hover */
|
||||
.dropdown-content a:hover {
|
||||
background-color: #f1f1f1
|
||||
}
|
||||
|
||||
/* Show the dropdown content on hover */
|
||||
.dropdown:hover .dropdown-content {
|
||||
display: block;
|
||||
}
|
||||
|
||||
/* Change background color of dropdown button on hover */
|
||||
.dropdown:hover .dropbtn {
|
||||
background-color: #3e8e41;
|
||||
}
|
||||
</style>
|
||||
|
||||
<div class="dropdown">
|
||||
<button class="dropbtn">Dropdown Menu</button>
|
||||
<div class="dropdown-content">
|
||||
<a href="#">Link 1</a>
|
||||
<a href="#">Link 2</a>
|
||||
<a href="#">Link 3</a>
|
||||
</div>
|
||||
</div>
|
||||
```
|
||||
|
||||
## 🛠️ 적용 사례 (Applied in summary)
|
||||
The two examples on the page are the applied demonstrations: a text dropdown box and a link-based dropdown menu, both shown as complete self-contained markup. No external project/commit applications found in the source.
|
||||
|
||||
## 💻 코드 패턴 (Code patterns)
|
||||
Core relative-parent / hover-reveal pattern (language: CSS):
|
||||
```css
|
||||
.dropdown {
|
||||
position: relative;
|
||||
}
|
||||
|
||||
.dropdown-content {
|
||||
display: none;
|
||||
position: absolute;
|
||||
}
|
||||
|
||||
.dropdown:hover .dropdown-content {
|
||||
display: block;
|
||||
}
|
||||
```
|
||||
|
||||
## ⚖️ 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 Advanced Dropdowns]], [[CSS Position]], [[CSS Navigation Bar]]
|
||||
- **참조 맥락:** Referenced whenever building hoverable menus, tooltips, or pop-over content panels in pure CSS.
|
||||
|
||||
## 📚 출처 (Sources)
|
||||
- [S1] W3Schools — CSS Dropdowns — https://www.w3schools.com/css/css_dropdowns.asp
|
||||
|
||||
## 📝 변경 이력 (Change history)
|
||||
- 2026-06-23: Initial draft synthesized from the W3Schools "CSS Dropdowns" page (Astra wiki-curation, P-Reinforce v3.1 format).
|
||||
Reference in New Issue
Block a user