Styling Radio Buttons

I’m attempting to make the radio buttons more visible in this contact form but despite adding CSS the outline of the radio buttons remain a bit too light.

span.wpcf7-list-item { display: table-row; }
span.wpcf7-list-item * { display: table-cell; }
.wpcf7 input[[type=”radio”] {
border: 3px solid #000000;
color: #000000;
}

I’m no expert on CSS so this may be completely wrong!

Would appreciate some ideas about how to rectify this.

Using Uncode theme. Chrome browser, SiteGround hosting, Mac !0.11.6 El Capitan.

Many thanks

Andy

The page I need help with: [log in to see the link]