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Updated: 2026年5月31日
Grid 3 Columns
Original task (JA): Gridで3列
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Conclusion
Grid 3 Columns — free browser-based HTML/CSS/JS practice
Why it matters in real projects
Gridで格子状のレイアウトが作れます。 Similar patterns appear daily in code review and production UI work.Step-by-step workflow
1. Read the guide and understand the goal of "Grid 3 Columns" 2. Review the HTML/CSS/JS 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: grid, grid-template-columns. 6. After success, continue with adjacent exercises in the same categoryCore concept explained
Gridで格子状のレイアウトが作れます。Technical focus
Key HTML elements in this task: div, style.Hint before you peek at the solution
display: grid; grid-template-columns: 1fr 1fr 1fr;Sample solution walkthrough
The solution uses HTML tags such as div, style. Check nesting and closing tags. CSS properties include display, grid-template-columns, gap. Watch selector spelling and specificity. Explanation: Gridで格子状のレイアウトが作れます。 Hint recap: display: grid; grid-template-columns: 1fr 1fr 1fr;Solution code
📝 Sample code
<div class="grid"><div>1</div><div>2</div><div>3</div></div>
<style>.grid { display: grid; grid-template-columns: 1fr 1fr 1fr; gap: 10px; }</style>Common mistakes for this exact task
・Skipping the hint: display: grid; grid-template-columns: 1fr 1fr 1fr;Troubleshooting
Q: Preview does not change after Run A: Ensure you edited the HTML/CSS/JS pane and clicked Run. Q: Looks correct but check fails A: Auto-check looks for output containing: grid, grid-template-columns. 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 "Grid 3 Columns" in your own words within 30 seconds ・Practice walking through each line of the sample solution on a whiteboard ・Be ready to discuss tags: div, style ・Discuss CSS properties: display, grid-template-columns, gap ・Prepare one alternative approach and why you chose this oneWhat to do after you pass
Move to the next exercise in the css-layout track, then continue the learning roadmap at /en/learning/layout/.Keywords
Free hands-on exercise covering Gridで3列, css-layout, 初級, div, style, display, grid-template-columns, gap, grid 3 columns—search-friendly guide for Grid 3 Columns.🧪 Try it here — safe to break things
Use the editor below to write code and preview instantly.
Jump to editor■ Exercise task
親divをGridにして、子要素を3列に並べてください。
Hint if stuck
display: grid; grid-template-columns: 1fr 1fr 1fr;