Contact button in product page

-- url of the page with the problem -- : chromothesis.gr/index.php/stickers/decor...81-green-round-trees
-- HikaShop version -- : 2.6.4
-- Joomla version -- : 3.6.4

I have this problem with buttons, I have both add to cart and contact button in the product page, which use the same css styling as you can see in the url below.

My question: How can I change the style of the "Contact" button only so it doesn't have the cart background image without changing all cart buttons??? In other words how can I modify the product display so the contact button points to a different button css style than the cart button?

chromothesis.gr/index.php/stickers/decor...81-green-round-trees

Thank you in advance!!!!

Exactly, both "add to cart" and "contact" buttons have the same classname:
class=" button hikashop_cart_input_button"
What I want to know is how to change one of the buttons to point to a new classname, like "button hikashop_CONTACT_input_button".
I can't find the php file containing the line that defines the button class.
In the product view there is a file called show_default.php that contains what I think is the code that Should be changed:

<div id="hikashop_product_contact_main" class="contact_button">
<?php
$contact = $this->config->get('product_contact',0);
if (hikashop_level(1) && ($contact == 2 || ($contact == 1 && !empty ($this->element->product_contact)))) {
$empty = '';
$params = new HikaParameter($empty);
global $Itemid;
$url_itemid='';
if(!empty($Itemid)){
$url_itemid='&Itemid='.$Itemid;
}
echo $this->cart->displayButton(JText :: _('CONTACT_US_FOR_INFO'), 'contact_us', $params, hikashop_completeLink('product&task=contact&cid=' . $this->element->product_id.$url_itemid), 'window.location=\'' . hikashop_completeLink('product&task=contact&cid=' . $this->element->product_id.$url_itemid) . '\';return false;');
}
?>
</div>
I just don't know how to change the button to point to another classname than the cart button.
Any help would be appreciated !!!!

Thank you!!

Never mind, I found it!!!!
I created a new css rule for
#hikashop_product_contact_main .button.hikashop_cart_input_button
with the characteristics I wanted for the contact button (background-image: none; )


THANK YOU ANYWAY!!!!