Update index.html

public/index.html

@@ -7,8 +7,8 @@
     <style>
       /* Style for the buttons */
       button {
-        background-color: gray;
-        color: black;
+        background-color: black;
+        color: yellow;
         font-size: 20px;
         padding: 12px 20px;
         border: none;
@@ -19,7 +19,7 @@
       
       /* Style for the logo */
       #logo {
-        float: top;
+        float: center;
         margin-right: 20px;
         margin-top: 20px;
         width: 100px;