Need help with child theme

I want to change the .bpfb_form_container, and list tabs and What’s new text color.

I’ve got the following from using Firefox – but not certain how and where to insert into child theme.

`.bpfb_form_container {

background-color: #ABABAB;

padding: 1em;

}

div.item-list-tabs {

background: none repeat scroll 0 0 #9D9D9D;

clear: left;

margin: 25px -19px 20px;

overflow: hidden;

}’

Plus want to change the “What’s New, ?” font color to #852929