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Updated: 2026年5月31日
Semantic Html
Original task (JA): セマンティックHTML
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Conclusion
Semantic Html — free browser-based HTML practice
Why it matters in real projects
セマンティックタグで構造が伝わりやすくなり、SEOやアクセシビリティに有利です。 Similar patterns appear daily in code review and production UI work.Step-by-step workflow
1. Read the guide and understand the goal of "Semantic Html" 2. Review the HTML editor pane and start from the starter code 3. Open hints if stuck; compare your diff with the sample solution 4. Click Run and inspect preview/console output 5. Auto-check looks for output containing: <header>, <main>, <footer>. 6. After success, continue with adjacent exercises in the same categoryCore concept explained
セマンティックタグで構造が伝わりやすくなり、SEOやアクセシビリティに有利です。Technical focus
Key HTML elements in this task: header, main, footer.Hint before you peek at the solution
headerが上、mainが中央、footerが下です。Sample solution walkthrough
The solution uses HTML tags such as header, main, footer. Check nesting and closing tags. Explanation: セマンティックタグで構造が伝わりやすくなり、SEOやアクセシビリティに有利です。 Hint recap: headerが上、mainが中央、footerが下です。Solution code
📝 Sample code
<header>ヘッダー</header>
<main>メインコンテンツ</main>
<footer>フッター</footer>Common mistakes for this exact task
・Skipping the hint: headerが上、mainが中央、footerが下です。Troubleshooting
Q: Preview does not change after Run A: Ensure you edited the HTML pane and clicked Run. Q: Looks correct but check fails A: Auto-check looks for output containing: <header>, <main>, <footer>. Look for typos, full-width spaces, or unclosed tags. Q: Console shows errors A: Open DevTools Console and fix bracket/quote mismatches at the reported line. Q: Hard to type on mobile A: Use landscape mode or continue on desktop—the same URL keeps progress in localStorage.Interview / portfolio tips
・Explain the techniques in "Semantic Html" in your own words within 30 seconds ・Practice walking through each line of the sample solution on a whiteboard ・Be ready to discuss tags: header, main, footer ・Mention responsive or accessibility trade-offs ・Prepare one alternative approach and why you chose this oneWhat to do after you pass
Move to the next exercise in the html-basic track, then continue the learning roadmap at /en/learning/html-basic/.Keywords
Free hands-on exercise covering セマンティックHTML, html-basic, 初級, header, main, footer, semantic html—search-friendly guide for Semantic Html.🧪 Try it here — safe to break things
Use the editor below to write code and preview instantly.
Jump to editor■ Exercise task
header, main, footer を使った基本構造を作ってください。mainの中身は自由です。
Hint if stuck
headerが上、mainが中央、footerが下です。