How to apply CSS to buttons?

I want apply CSS to all my buttons but not referencing all buttons id in my CSS stylesheet. How to proceed?

<button id="buttonEdit">Save</button>

I already try:

input[type=button]
{
    fonr-size: 80%;
}

but this doesn't work.

Thank you.

button, input[type=button]
{
    font-size: 80%;
}

The element is button, not input

You are referring to a button, not an input field, so you should use the correct term in css.

button
{
    font-size: 80%;
}

You are not using an input with type="button", but a button element:

button
{
    font-size: 80%;
}

Do you have styles associated with the buttonEdit id in your CSS?

I've just copied in your button to a "Try It Yourself" area on W3Schools, and added my own style in the header

button { font-size: 80%; }

As everyone else has already posted, and it worked. I did a before test to see the button, then added the style & refreshed. Button text got smaller.

If there are no styles associated with buttonEdit that could be messing things up, then I'd triple check you didn't accidentally forget the colon after font-size.

A quick and nasty fix is just to put style="style:value;" in every button tag.