Add a button for each platform and configure an action set for each button. In each action set, specify a click event and add an action that opens the vendor's URL in a window.

Add one button and configure three action sets. In each action set, specify a click event and add an action that opens the vendor's URL in a window.

Add one button and configure one action set. In the action set, specify a click event with three actions to open each vendor URL in a window. Apply a when rule to each action to determine the correct URL.

Add three check boxes and one button. For each check box, configure an action set with a click event to set the value of the URL. For the button, configure an action set with a click event to open the URL in a window.