the correct variable name is message
(not var_message)
variable message is populated in controller Mage_Wishlist_IndexController
inside method sendAction
here it is:
$emailModel = Mage::getModel('core/email_template');
$sharingCode = $wishlist->getSharingCode();
foreach ($emails as $email) {
$emailModel->sendTransactional(
Mage::getStoreConfig('wishlist/email/email_template'),
Mage::getStoreConfig('wishlist/email/email_identity'),
$email,
null,
array(
'customer' => $customer,
'salable' => $wishlist->isSalable() ? 'yes' : '',
'items' => $wishlistBlock,
'addAllLink' => Mage::getUrl('*/shared/allcart', array('code' => $sharingCode)),
'viewOnSiteLink' => Mage::getUrl('*/shared/index', array('code' => $sharingCode)),
'message' => $message
)
);
}
$wishlist->setShared(1);
$wishlist->save();
and the actual content of the message comes from a form input and gets fetched over here:
$message = nl2br(htmlspecialchars((string) $this->getRequest()->getPost('message')));
there is no actual styling or css assigned to it. In fact most of styles are defined inline
in email templates