Hi John,
1) Create a radio field. Give it a few values. For this example, set the field name to ‘my_radio’
2) Save the fieldset (shouldn’t be needed but just in case)
3) Create an image field
4) At the bottom, set Conditional Logic to “Yes”
5) In the dropdowns, select “my_radio” then “is equal to” and the last box should show a list of the options you entered into the radio field.
Getting the field info up to the body element is going to be tricky because of how/where you position the loop. Instead of using inline styles you could create a javascript block that adds that $style line to the body element. Something like jQuery('body').css('background-color', <?php echo $color; ?>); where the css line would change depending on the conditional check in my first reply.
No idea how to do the dynamic style sheet thing. 🙂
