How to allow up/down arrows to show up on ipad

I have this code:

input[type=number]::-webkit-inner-spin-button, input[type=number]::-webkit-outer-spin-button {
opacity: 1;
}

It works fine on windows/Mac browsers.

However, the up/down arrows disappear when I use my ipad to open the web. Could anyone give me a solution for this? Thanks!