# night light challenges Coding challenges for the night light tutorial. #docs ## Before we get started Complete the following guided tutorial: * [tutorial](/microbit/lessons/night-light/tutorial) At the end of the tutorial, click `keep editing`. Your code should look like this: ``` led.setBrightness(255) led.plotAll() input.onButtonPressed(Button.A, () => { led.setBrightness(64) }) ``` ### Challenge 1 ### @video td/videos/night-light-2 What if we want to turn off all the LEDs? Let's do this by setting the brightness to `0` when button `B` is pressed. Add an event handler with `input->on button pressed(B)` add `led->set brightness(0)` to turn off the LEDs. ``` led.setBrightness(255) led.plotAll() input.onButtonPressed(Button.A, () => { led.setBrightness(64) }) input.onButtonPressed(Button.B, () => { led.setBrightness(0) // *** }) // *** ``` **Challenge 3** Add an event handler with `input->on screen up` to change the LED brightness back to a `255`. * `Run main` your script to see the LEDs change brightness.