What is the proper CSS style for "SegoeLight"?

No spaces in CSS fontface names, and HTML in general. You should never have a space in any kind of title/pathname/etc. Based off of what you just wrote, you'd need to define it as "SegoeUILight"

Spaces are used in CSS, but for separation and defining very specific rules, like defining an LI within a Div with an ID.

#divID li

Or defining an LI within a UL that has a class within a Div with an ID.

#divID ul.className li

Can get pretty complicated.

Where did you download this font kit? It should have come with declarations you can just copy and paste.

No spaces in CSS fontface names, and HTML in general. You should never have a space in any kind of title/pathname/etc. Based off of what you just wrote, you'd need to define it as "SegoeUILight"

Um, since when?  There are a lot of font families with spaces...

Times New Roman, Trebuchet MS, Arial Black, Lucida Sans Unicode, Lucida Grande, etc, etc, etc.  You just surround them with quotes.

As a rule of thumb with CSS font face kits. System fonts are different and already localized on a user's machine, but font face kits pull remotely and you need to load them with correct pathnames. Why have the fonts named 2 different ways and confuse yourself along the way?

I've asked a couple times now where you have acquired the font so i may help you in more detail. If you are having issues with my comments, please feel free to disregard and wait for another expert to help you out. Good luck.

If you are having issues with my comments, please feel free to disregard and wait for another expert to help you out. Good luck.

I'm not the OP.  He hasn't responded yet.

I see that, but assumed you were inquiring on the same issue as you were responding directly to my comments. I've gotten much help over time from reading other user's posts and am sure I'm not the only one ;^)

NP, just didn't want you to think the OP was harassing you or anything. :)

So far the designer we are building the website for doesn't see the SegoeLt or Segoe UI font when we use it in a font family. She only sees the Arial portion

font-family:SegoeLt, "Segoe UI", Arial, Helvetica, sans-serif;

The font-family declaration will depend on how the font is defined on the @font-face declaration. Reference my 1st comment above. She must make sure the @font-face is at the top of the style sheet, before it is called in the font-family rule.

Sorry for any confusion on this - what I meant to say is that our designer is viewing the web page we developed, and is seeing an Arial font, even though we coded the Segoe font in our stylesheet:

font-family:SegoeLt, "Segoe UI", Arial, Helvetica, sans-serif;

I knew what you meant :-)

Can you please attach code or try the above method?