feat(game)!: Fixed polling, SPA, Gameplayloop etc. (#59)

Co-authored-by: LQ63 <lkhermann@web.de>
Reviewed-on: #59
Co-authored-by: Janis <janis.e.20@gmx.de>
Co-committed-by: Janis <janis.e.20@gmx.de>

knockoutwhistweb/app/assets/stylesheets/main.less

@@ -49,6 +49,16 @@
   box-shadow: 3px 3px 3px @highlightcolor;
 }
 
+.inactive::after {
+  content: "";
+  position: absolute;
+  inset: 0;             /* cover the whole container */
+  background: rgba(0, 0, 0, 0.50);
+  z-index: 10;
+  border-radius: 6px;
+  pointer-events: none; /* user can't click through overlay */
+}
+
 .bottom-div {
   position: fixed;
   bottom: 0;