Hi yellowyunicorn,

The problem is being caused by the Jetpack plugin, you can either fix this by disabling Jetpack or if you want to keep using it then add this CSS to Custom CSS:

@media only screen and (min-width: 600px) {
    .contact-form input[type=email], .contact-form input[type=tel], .contact-form input[type=text], .contact-form input[type=url] {
        width: unset;
    }
}
.contact-form input[type=email], .contact-form input[type=tel], .contact-form input[type=text], .contact-form input[type=url] {
    box-sizing: unset;
    margin-bottom: unset;
}
.contact-form label {
    margin-bottom: unset;
}
.contact-form .form-group.labeled-textarea-row label {
    border-bottom-color: transparent !important;
}

Have a nice day!