Columns not responsive on mobile

Hello,

I have a form with a 3-column layout in the first row, and the fields get quite small on mobile. I tried some things with the CSS to see if I could get the columns to fill the whole row, but I’m not having any luck. My latest unsuccessful attempt is below. Can you advise on what I’m doing wrong?

@media screen and (max-width: 610px) {
.fm-form .wd-width-30 {
width: 100% !important;
}
}

Thanks for your help!
Sabina

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