В css:
body { font-family: "wf_SegoeUILight"; }
@font-face{
font-family: 'wf_SegoeUILight';
src:url('http://i.s-microsoft.com/fonts/Segoe-UI/Cyrillic/Light/latest.eot');
src:url('http://i.s-microsoft.com/fonts/Segoe-UI/Cyrillic/Light/latest.eot?#iefix') format('embedded-opentype'),
url('http://i.s-microsoft.com/fonts/Segoe-UI/Cyrillic/Light/latest.woff') format('woff'),
url('http://i.s-microsoft.com/fonts/Segoe-UI/Cyrillic/Light/latest.ttf') format('truetype'),
url('http://i.s-microsoft.com/fonts/Segoe-UI/Cyrillic/Light/latest.svg#web') format('svg');
font-weight: normal;
font-style: normal;
}