Remove all: revert from .btn class

Remove 'all: revert' from .btn class in index.html.

Author: petter-a

index.html

@@ -89,7 +89,6 @@
             max-width: none;
           }
           .btn {
-            all: revert;
             align-items: center;
             appearance: none;
             background-color: rgb(118, 35, 47);