Algodoo

The keys are very difficult to read because you have white numbers on very light-colored keys. You can fix that by: Right-click on a key, then hover your cursor over "text". When the text configuration panel shows, simply click on the color black. Do that for all keys, then save your edited scene and upload it to Algobox. Problem solved!

Oh, one more thing: There's no reason to have clouds floating by for a calculator! You can disable the clouds this way: Right click on the background, then uncheck the "draw clouds" checkbox.

@Xray
Improvements have been made in accordance with your suggestion. I tried and found that it was not very nice to change the text to black, so I changed the text to other darker colors.
In addition, my English ability is not very good, if there are any words or grammatical errors in the instructions, please point out that I will correct it as soon as possible

Your calculator buttons are much easier to read now. Good job!

Oh, here is one more suggestion that I should have mentioned before but I forgot to. The display begins with "undefined" which is not normal for a calculator. You can fix that by initializing the variable scene.my.display with a value of zero. You can do that by placing scene.my.display = 0 in onSpawn. It will look like this: onSpawn = (e)=> {scene.my.display = 0 }

@Xray
Thanks for your advice, but the calculator will not work before clicking AC for the first time, which is equivalent to the fact that the calculator is not powered on in real life, so I changed the script of the display screen, so that it does not display any content when the variable scene.my.display is undefined

Good point!