Make device selection CPU-safe

app.py

@@ -15,9 +15,14 @@ MODEL_ID = "sbintuitions/kana-whisper"
 
 # ZeroGPU exposes CUDA at startup, so we can load straight onto the GPU. The
 # @spaces.GPU decorator on transcribe() is what actually reserves the slice at
-# call time; on non-ZeroGPU hardware the decorator is a no-op.
-device = "cuda"
-torch_dtype = torch.float16
+# call time; on non-ZeroGPU hardware the decorator is a no-op. We detect the
+# device so the Space still builds/runs on plain CPU hardware (just slower).
+if torch.cuda.is_available():
+    device = "cuda"
+    torch_dtype = torch.float16
+else:
+    device = "cpu"
+    torch_dtype = torch.float32
 
 model = AutoModelForSpeechSeq2Seq.from_pretrained(
     MODEL_ID,