MacBook Air Totally Dead

Hello! Two days ago I discovered my Macbook Air 13” (2013) was “dead.” The evening before, I’d used it as normal, with no issues at all. The battery had quite a bit of charge left, as I recall (>70%). Next morning, it wouldn’t turn on, and when I plugged in the power cord/charger, the light did NOT light up either orange or green. I tried the SMC reset steps I read about on Apple’s support forum, but nothing. There are no sounds coming from it, nothing at all happens. I thought this might be a battery issue at first, so ordered a replacement battery (it hasn’t arrived yet), but now I’m thinking this is probably something else. If you can help me figure out what I need to order/replace, or if it’s not worth my trying, I’d be so grateful. Thanks!!