Clairos Learn Interactive UNIX, Web, and AI Operations lessons for practical technical skills
Sandbox

Practice Web snippets freely.

Use the simulated Web editor for scratch snippets, preview checks, hints, resettable tasks, and launch habits.

Track progress 0/120 lessons 0/18 missions 12 courses
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Web fundamentals lab Simulated editor
New learnerrank 0XP 0%complete
Current edit

Open a project file

Choose a project file, make one bounded edit, and press Run.

Target
index.html
Evidence
The safe checker will report the pattern it found.
index.html html
Preview allowlisted render
Console text only
Sandbox prompts
  • Load an exact snippet, press Run, then use Check after all tasks are complete.
  • Build a tiny HTML section with one heading, one paragraph, and one clear class name.
  • Add CSS spacing with display: grid, gap, padding, and a responsive media query.
  • Practice a simulated JavaScript event with querySelector, addEventListener, and textContent.
  • Review a form label, required input, help text, and accessible confirmation state.
  • Finish a launch check with a title, meta description, canonical URL, and 404 route note.
Mission board
HTML basics builder

Finish every html basics lesson and complete its persistent projects.

250 XP
Semantic structure builder

Finish every semantic structure lesson and complete its persistent projects.

270 XP
Links and media builder

Finish every links and media lesson and complete its persistent projects.

290 XP
CSS basics builder

Finish every css basics lesson and complete its persistent projects.

310 XP
Layout and responsive builder

Finish every layout and responsive lesson and complete its persistent projects.

330 XP
Visual polish builder

Finish every visual polish lesson and complete its persistent projects.

350 XP
JavaScript basics builder

Finish every javascript basics lesson and complete its persistent projects.

370 XP
DOM and events builder

Finish every dom and events lesson and complete its persistent projects.

390 XP
Forms and validation builder

Finish every forms and validation lesson and complete its persistent projects.

410 XP
Accessibility builder

Finish every accessibility lesson and complete its persistent projects.

430 XP
SEO, performance, and hosting builder

Finish every seo, performance, and hosting lesson and complete its persistent projects.

450 XP
Capstone builds builder

Finish every capstone builds lesson and complete its persistent projects.

470 XP
First Web page

Complete the first HTML lesson and save the page-building loop.

100 XP
Structure checkpoint

Complete semantic structure and links/media foundations.

160 XP
CSS checkpoint

Complete the first CSS and responsive layout lessons.

180 XP
JavaScript checkpoint

Practice simulated JavaScript basics and DOM event patterns.

190 XP
Forms and accessibility

Complete form labels, validation hints, and accessibility naming.

200 XP
Launch review

Complete SEO/performance basics and a first capstone build.

240 XP