XF 1.5 Access the background-image value from a Style Property?

[Nulumia]

Wondering if it's possible to access just the background-image value of a standard CSS based property.

For example, we could call from a template:

.content {
color: @primaryContent.color
}

.. or even render out all background items as a set:

.content {
{xen:property "primaryContent.background"}
}

..which would print:

.content {
background-color: #fff;
background-image: url("...");
backgorund-repeat: etc...
}

However, if I try to call the individual image value from this set:

.content2 {
background-image: @primaryContent.background-image;
}

it won't work. Is there a special attribute to call for this value only?

Much thanks