Allow playing/pausing with spacebar

src/Controls.tsx

@@ -1,4 +1,4 @@
-import React from 'react';
+import React, { useEffect } from 'react';
 
 interface Props {
   running: boolean;
@@ -33,6 +33,14 @@ const Controls = (props: Props) => {
     }
   };
 
+  useEffect(() => {
+    document.addEventListener('keyup', (e) => {
+      if (e.key === ' ') {
+        toggle();
+      }
+    });
+  }, [toggle]);
+
   return (
     <div className="controls">
       <div className="controls__section dimensions">