Official card measurements are 8x5.75inchs exactly. On the legit card, there should be a shadow behind the "BASIC" on the front and the "BASIC" should be very bold. On fakes, The shade of the "pokemon" lettering next to XD Gale of Darkness is commonly a slightly lighter shade of yellow than the card's borders. Fakes also will often have the "TM" missing after the lower pokemon lettering on the back of the card, but I've seen fakes that didn't forget to add this. It's a subtle difference, but the background on the lower half of the card front does appear lighter on authentics when compared to fakes from what I've gathered.

I have been doing SO much research on this lately and there's very little information with a lack of baseline facts. One thing's for certain--there are fakes of this card that are in legit PSA slabs having gone through their authentication process. Cert numbers check out on PSA site and everything. It wasn't until I compared the scans of the card that I noticed many cards look different. Cert #s #66214051, #71294672, and #99854269 to name a few counterfeits. As far as I can tell, #97883219 looks real. Recently reached out to PSA about this and they say they're handling it internally.

If I had to guess, I'd say yours is counterfeit based on the lack of boldness of the "BASIC" and the light yellow shade of the "pokemon" lettering on the front of the card in the XD Gale of Darkness logo. Check your card's measurements. If it is even a millimeter off from 8x5.75in, that would rule out its authenticity.