Aligning content

I am trying to align an additiona line of text I’ve added to be centered by I can’t quite work it out. Here is the css I am using:

.site-description:after {
display: block;
content:”Weddings | Parties | Birthdays | Corporate | Events | Christenings | Funerals | Any type of Celebration”;
font-size: 15px !important;
font-family: lato;
color: white !important;
font-weight:100;
position: absolute;
visibility: visible;
text-align: center;
}

Can someone help me to centre this line please?

Thanks ??

The page I need help with: [log in to see the link]