Update app.py

Change gradients to black

app.py

@@ -356,7 +356,7 @@ body {
 }
 
 .custom-button {
-    background: linear-gradient(271.15deg, #00C7E2 0.27%, #00CC6A 48.52%, #70FF00 102.07%);
+    background: #1E2125;
     font-size: 30px;
     color: white;
     padding: 10px 20px;
@@ -372,7 +372,7 @@ body {
 
 .custom-title {
     font-size: 36px;
-    background: linear-gradient(271.15deg, #00C7E2 0.27%, #12C06D 102.07%);
+    background: #1E2125 text;
     -webkit-background-clip: text;
     -webkit-text-fill-color: transparent;
     font-weight: bold;