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10_Wiki/Topic_Programming/Topic_W3CSS/W3CSS_Dropdowns.md

@@ -0,0 +1,83 @@
+---
+id: w3css-dropdowns
+title: "W3CSS Dropdowns"
+category: "Programming_Language"
+status: "draft"
+verification_status: "conceptual"
+canonical_id: ""
+aliases: ["w3-dropdown-hover", "w3-dropdown-click", "W3.CSS 드롭다운"]
+duplicate_of: ""
+source_trust_level: "B"
+confidence_score: 0.87
+created_at: 2026-07-04
+updated_at: 2026-07-04
+review_reason: ""
+merge_history: []
+tags: ["w3css", "css-framework", "w3schools", "dropdown", "navigation"]
+raw_sources: ["https://www.w3schools.com/w3css/w3css_dropdowns.asp"]
+applied_in: []
+github_commit: ""
+---
+
+# [[W3CSS Dropdowns]]
+
+## 🎯 한 줄 통찰 (One-line insight)
+`w3-dropdown-hover` and `w3-dropdown-content` place NO constraint on element type — the source explicitly demonstrates the exact same dropdown behavior using `<button>`+`<div>`, then `<p>`+`<span>`, proving the pattern is a pure CSS relationship (hover state on parent reveals a positioned child), not tied to any specific semantic markup. [S1]
+
+## 🧠 핵심 개념 (Core concepts)
+- **`w3-dropdown-hover`** — marks an element as a hoverable dropdown trigger; any element type works. [S1]
+- **`w3-dropdown-content`** — the content revealed on hover/click; hidden by default, shown via CSS `:hover` or JS-toggled class. [S1]
+- **`w3-dropdown-click`** — clickable variant; requires JavaScript to explicitly toggle a `w3-show` class since there's no `:hover` state to rely on. [S1]
+- **`w3-show`** — the class JS toggles on/off to reveal/hide click-based dropdown content. [S1]
+- **Animation composability** — any `w3-animate-*` class can be added directly to `w3-dropdown-content` for a fade/zoom/slide reveal. [S1]
+- **Right-aligned positioning** — combining `w3-right` (float) with inline `right:0` CSS makes the dropdown content open right-to-left instead of left-to-right. [S1]
+
+## 📖 세부 내용 (Details)
+- Hover dropdown with any element types: `<p class="w3-dropdown-hover">Hover over me!<span class="w3-dropdown-content w3-green">Hello World!</span></p>`. [S1]
+- Click dropdown with JS toggle: `<div class="w3-dropdown-click"><button onclick="myFunction()" class="w3-button w3-black">Click Me!</button><div id="Demo" class="w3-dropdown-content w3-bar-block w3-border">...</div></div>` with `function myFunction() { var x = document.getElementById("Demo"); if (x.className.indexOf("w3-show") == -1) { x.className += " w3-show"; } else { x.className = x.className.replace(" w3-show", ""); } }`. [S1]
+- Animated dropdown content: `<div id="Demo" class="w3-dropdown-content w3-bar-block w3-animate-zoom">`. [S1]
+
+## ⚖️ 모순 및 업데이트 (Contradictions & updates)
+- **hover vs click 방식의 근본적 차이**: w3-dropdown-hover는 순수 CSS :hover로 동작하지만 w3-dropdown-click은 JavaScript로 w3-show 클래스를 수동 토글해야 한다는 구조적 차이가 있음. [S1]
+
+## 🛠️ 적용 사례 (Applied in summary)
+현재 발견된 실제 적용 사례가 없습니다 — 네비게이션 바 안에 드롭다운 메뉴를 넣는 조합이 다음 챕터(Navigation Bars)에서 본격적으로 다뤄지는 실전 활용의 시작점이다. [S1]
+
+## 💻 코드 패턴 (Code patterns)
+Clickable dropdown toggled via JavaScript's w3-show class (HTML/JS):
+```html
+<div class="w3-dropdown-click">
+  <button onclick="myFunction()" class="w3-button w3-black">Click Me!</button>
+  <div id="Demo" class="w3-dropdown-content w3-bar-block w3-border">
+    <a href="#" class="w3-bar-item w3-button">Link 1</a>
+  </div>
+</div>
+<script>
+function myFunction() {
+  var x = document.getElementById("Demo");
+  if (x.className.indexOf("w3-show") == -1) {
+    x.className += " w3-show";
+  } else {
+    x.className = x.className.replace(" w3-show", "");
+  }
+}
+</script>
+```
+
+## ✅ 검증 상태 및 신뢰도
+- **상태:** draft
+- **검증 단계:** conceptual
+- **출처 신뢰도:** B (W3Schools — widely used educational reference, not a primary standards body)
+- **신뢰 점수:** 0.87
+- **중복 검사 결과:** 신규 생성 (New discovery)
+
+## 🔗 지식 그래프 (Knowledge Graph)
+- **상위/루트:** [[W3.CSS Tutorial]]
+- **관련 개념:** [[W3CSS Bars]], [[W3CSS Accordions]], [[W3CSS Navigation]]
+- **참조 맥락:** hover/click 기반 콘텐츠 공개 패턴 — 아코디언(Accordions) 챕터와 직접 대비됨.
+
+## 📚 출처 (Sources)
+- [S1] W3Schools — W3.CSS Dropdowns — https://www.w3schools.com/w3css/w3css_dropdowns.asp
+
+## 📝 변경 이력 (Change history)
+- 2026-07-04: Initial draft synthesized from the W3Schools "W3.CSS Dropdowns" page (Astra wiki-curation, P-Reinforce v3.1 format).