Why does the datetime-local input display as gray on mobile devices but normal on computers?
Should I adjust the CSS or implement responsive web design (RWD) to address this issue?

.form-area input{
    display: block; /*展現block元素*/
    margin: 15px;
    padding: 10px;
    margin-left: 0px;
    margin-right: 0px;
    width: 300px;
}

.form-area{
    font-size: 14px;
    font-weight: bold;
}

[[enter image description here](https://i.stack.imgur.com/y9SvY.jpg)](https://i.stack.imgur.com/SOkMW.jpg)

I hope to resolve this issue on mobile devices.