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Render a simulated preview from the current lesson snippet.
Buttons, focus states, hierarchy, rhythm, and professional restraint.
Build button hierarchy inside the persistent Learning journal: Button hierarchy starter project.
Core 02 Visual polish Visual polish: Focus ringsBuild focus rings inside the persistent Product changelog: Focus rings starter project.
Core 03 Visual polish Visual polish: Card rhythmBuild card rhythm inside the persistent Workshop signup: Card rhythm starter project.
Core 04 Visual polish Visual polish: Readable contrastBuild readable contrast inside the persistent Incident summary: Readable contrast starter project.
Core Checkpoint 05 Visual polish Visual polish: Status colorsBuild status colors inside the persistent Community workshop: Status colors starter project.
Core 06 Visual polish Visual polish: Subtle shadowsBuild subtle shadows inside the persistent Neighborhood library: Subtle shadows starter project.
Core 07 Visual polish Visual polish: Consistent radiiBuild consistent radii inside the persistent Volunteer check-in: Consistent radii starter project.
Core 08 Visual polish Visual polish: Visual polish checkpointBuild visual polish checkpoint inside the persistent Local event guide: Visual polish checkpoint starter project.
CoreCreate a free account to sync completed lessons, XP, streaks, course status, and your next lesson across sessions.
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Progress sync stores completion IDs, scores, streaks, badges, and game settings. Terminal contents, editor snippets, lab scratch, email, and real names are never published on leaderboards or share cards.
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Render a simulated preview from the current lesson snippet.
Check
Save the lesson after the required task snippets are complete.
Hint
Show the lesson hint without changing progress.
Reset
Clear local Web lab scratch state for this browser.
<!doctype html>
Start an HTML document with an explicit standards-mode marker.
<header> <main> <section> <footer>
Use semantic landmarks so pages have structure.