@ian : Login to your WordPress Dashboard Go to Appearance => Customize => Additional css and add the following css .
@media only screen and (max-width: 480px) {
.gform_wrapper .field_sublabel_below .ginput_complex.ginput_container label,
.gform_wrapper .field_sublabel_above .ginput_complex.ginput_container label{
display:inline !important;
}
img[class*="align"], img[class*="wp-image-"] {
max-width:90%;
}
.gform_wrapper {
margin:16px;
}
}
Let me know if this resolves your issue. Actually this is not a theme related issue. Its due to the plugin css of gravity form.
Regards,
Tikaram