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UI · Frontend challenge · Frontend UI
Traffic Light
Difficulty
medium
Time
~25m
Format
Single
Grading
Human review
#ui#react#frontend#state#timers
Mission file // read carefullymedium
Build a Traffic Light that cycles green → yellow → red → green automatically on a timer, highlighting the active light (others dimmed). Use different durations per light if you like.
Build with
ReactLive preview as you type
Human review
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