Keep improving one project from an empty folder to a responsive one-page site with an introduction, projects, and contact details. Every lesson adds a visible result or a check toward that finish line.
Curriculum
Personal brand site build path
01
Start With Codex
Set up Codex and build the hero section of your personal brand site.
Implement the approved theme switch only after defining visible, checkable completion criteria. This closes the plan-to-proof loop from the previous lesson.
Before you start
Open the approved theme-switch plan from the previous task.
Preview index.html and confirm the Projects button still moves to the right section before editing.
Do it now
Good prompt
Codex, implement the approved accessible light/dark theme switch in index.html. Keep one file, add no packages, and preserve the existing Projects button. Done when: (1) the theme control has a clear accessible label, (2) switching twice visibly returns to the starting theme, (3) the Projects button works in both themes, (4) wide and narrow layouts have no horizontal overflow, and (5) you report the changed file plus the result of every check.
What success looks like
A clearly labeled control switches the page between light and dark themes.
The Projects button still works in both themes.
The page works at wide and narrow widths, and the final report lists each check separately.
Stuck? Try this
If Codex says “done” without evidence, paste the checklist again and ask for one result per condition.
If the original button breaks, ask Codex to reproduce that regression before making the smallest fix.
Plain-language explanation
“Done” should mean more than “Codex stopped editing.” A good done condition says what behavior changed and what evidence proves it.
Done-when criteria can include passing tests, a successful build, a screenshot, a browser check, or a clear explanation of remaining risk.
Why it matters
Completion criteria protect you from vague success. Codex can report exact evidence instead of asking you to trust that the change worked.
Common beginner mistake
The common mistake is accepting a confident final message without a command, output, or manual check you can verify.
Try this
Take a task and add two done-when bullets: one automated check and one human-readable behavior check.
Completion checklist
Your request includes at least two done conditions.
The final evidence can be checked without reading every edited line.