add fullscreen button

script.js

@@ -661,8 +661,9 @@ class Board {
     this.buttons.optFancy = this.addButton(x0, cfgy0, 'Effects:', 'config');
     this.buttons.optBlockedEffect = this.addButton(x0, cfgy0+ysp2, 'Dim Blocked:', 'config');
     this.buttons.optSloppy = this.addButton(x0, cfgy0+ysp2*2, 'Sloppy Mode:', 'config');
+    this.buttons.toggleFullscreen = this.addButton(x0, cfgy0+ysp2*-1.5, 'Fullscreen', 'config');
 
-    this.buttons.btnAbout = this.addButton(x0, cfgy0+ysp2*-1.5, 'Help', 'config');
+    this.buttons.btnAbout = this.addButton(x0, cfgy0+ysp2*-2.5, 'Help', 'config');
   }
 
   updateSettingsGUI(cfg) {
@@ -1646,6 +1647,15 @@ class Game {
         allowTemplateAugmenting: !this.cfg.allowTemplateAugmenting,
       })
     });
+
+    this.board.buttons.toggleFullscreen.addEventListener('click', () => {
+      this.info("Toggle Fullscreen");
+      if (document.fullscreenElement) {
+        document.exitFullscreen();
+      } else {
+        this.board.$svg.requestFullscreen();
+      }
+    });
   }
 
   /**

style.css

@@ -16,6 +16,7 @@ html, body {
 #board {
 	height: 100%;
 	width: 100%;
+	background: #201717;
 }
 
 .disabled .orb {