Update app.py

app.py

@@ -1,9 +1,29 @@
 import gradio as gr
 
-with gr.Blocks() as app:
-    gr.Markdown("""
-    ### OptionStrat Flow
-    [<span style="padding: 10px 20px; background-color: #0056b3; color: white; border-radius: 5px;">Truy cập Option Flow</span>](https://optionstrat.com/flow){:target="_blank"}
-    """)
+with gr.Blocks(css="""
+body { background-color: #111; color: white; }
+#main { display: flex; justify-content: center; align-items: center; height: 90vh; }
+.button-link {
+    display: inline-block;
+    padding: 12px 24px;
+    background-color: #007bff;
+    color: white;
+    font-size: 18px;
+    border-radius: 8px;
+    text-decoration: none;
+    text-align: center;
+    border: 1px solid white;
+}
+.button-link:hover {
+    background-color: #0056b3;
+}
+""") as app:
+    with gr.Column(elem_id="main"):
+        gr.Markdown("""
+        ### OptionStrat Flow  
+        <a class="button-link" href="https://optionstrat.com/flow" target="_blank">
+        Truy cập Option Flow
+        </a>
+        """, elem_id="options")
 
 app.launch()