feat: initial commit

scripts/app.js

@@ -0,0 +1,44 @@
+(function () {
+  'use strict';
+
+  var slides = [],
+  currentSlideNumber = 0,
+  slideNext,
+  slidePrev;
+
+  function $$(selector){
+    return Array.prototype.slice.call(document.querySelectorAll(selector), 0);
+  }
+
+  function moveSlides() {
+    slides.forEach(function (item, index, array) {
+      if (index < currentSlideNumber) {
+        item.setAttribute('janus-timeline', 'past');
+      } else if (index == currentSlideNumber) {
+        item.setAttribute('janus-timeline', 'present');
+      } else {
+        item.setAttribute('janus-timeline', 'future');
+      }
+    });
+  }
+
+  var init = function() {
+    slides = $$('main>section');
+    currentSlideNumber = 0;
+    shortcut.add('Page_down', function() {
+      if (currentSlideNumber < slides.length - 1) {
+        currentSlideNumber++;
+        moveSlides();
+      }
+    });
+    shortcut.add('Page_up', function() {
+      if (currentSlideNumber > 0) {
+        currentSlideNumber--;
+        moveSlides();
+      }
+    });
+    moveSlides();
+  }
+
+  document.addEventListener("DOMContentLoaded", init);
+})();