Challenge

Countdown Timer

Medium

javascript

Build a countdown timer that counts down from a set number of seconds, such as 60, and shows the time as MM:SS. It ticks down once a second and stops at 00:00.

Notes:

The starter's <p id="timer"> already reads 01:00. Update its text on every tick.
Both parts are always two digits, so five seconds reads 00:05.

Check your work against

Displays time in MM:SS format
Counts down automatically once per second after the page loads
Stops exactly at 00:00 — never goes negative

No automatic grading

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