Help About Spoiler Content Xenforo 1.5.12

I need your help admin

I've created a new user group called Mask Bandit. All I want to do is my spoiler content is meant or viewable only to Mask Bandit group not member group

This is the code :

<xen:require css="bb_code.css" />

<xen:comment><!-- content is escaped via parser --></xen:comment>
<xen:if is="{$visitor.user_id}">
<div class="ToggleTriggerAnchor bbCodeSpoilerContainer">
<button class="button bbCodeSpoilerButton ToggleTrigger Tooltip JsOnly"
title="{xen:phrase click_to_reveal_spoiler}"
data-target="> .SpoilerTarget"><span>{xen:phrase spoiler}{xen:if $titleHtml, ': <span class="SpoilerTitle">{xen:raw $titleHtml}</span>'}</span></button>
<div class="SpoilerTarget bbCodeSpoilerText">{xen:raw $content}</div>
</div>
<xen:else />
<button class="button" title="{xen:phrase click_to_reveal_spoiler}"><span>You need to register to view spoilers!</span></button>
</xen:if>

How to modify this code ?