Keypress Shift for zoom image scale – card styling

I have this code here I want to be active only when the key “Shift” is pressed. I still haven’t been able to figure out how to do it, neither of these two styling codes seem to work
Alternative 1

{
window.addEventListener("keydown", checkKeyPress, false);

function checkKeyPress(zio) {
 if (zio.keyCode == "16") {
 html:not(.mobile) #io-wrapper:hover {
transform: scale(1.5);
transform-origin: top left;,
)
}
 }

alternative 2:

 If(event.shiftKey)
{
 html:not(.mobile) #io-wrapper:hover {
transform: scale(1.5);
transform-origin: top left;,
} 

Any help would be highly appreciated