refactor: polish guide

app.py

@@ -113,9 +113,11 @@ with gr.Blocks() as demo:
     with gr.Tab("App"):
         with gr.Row():
             gr.Textbox(
-                "Welcome to visit ECG-Delineation space.",
+                """Welcome to visit ECG Delineation space.
+The following three tables represent the train, validation, and test datasets, which have been meticulously stratified from the LUDB dataset. These datasets were used for training and evaluating the models.
+Usage: By clicking on the desired record in one of the tables below, the P, QRS, and T wave segments will be inferred by HRNetV2 and displayed as an image at the bottom. Additionally, the post-processed results based on predefined thresholds will also be displayed alongside.""",
                 label="Information",
-                lines=1,
+                lines=3,
             )
         gr_dfs = []
         with gr.Row():