Styling

add this css to your stylesheet:

fieldset {
    border: 1px solid #d1d1d1;
    margin: 0 0 1.75em;
    min-width: inherit;
    padding: 0.875em;
}

legend {
    border: 0;
    padding: 0;
}

You might want to add !important to every rule if it still doesn’t show up.
foe example:

border: 1px solid #d1d1d1 !important;