Add logo to bottom of login pages

How can I add a logo to the bottom part of the login and error pages?

Step-by-step guide

To add a logo to the bottom part of the login and error pages, use the custom CSS function described in detail in the Ubisecure SSO Login UI Customization document.
 
 An example #footer code is given below: 

#footer
#footer {
	background-image: url("https://ubilogin.ubisecure.com/extranet/css/images/logo.png ");   
	background-position: center center;   
	background-repeat: no-repeat;   
	padding-top: 150px;   
	text-align: center; 
}