Kind of works

src/page/background/background.scss

@@ -3,8 +3,8 @@
 @include responsive() using ($vars) {
   div.background-element {
     position: absolute;
-    left: 0;
     top: 0;
+    left: 0;
     border-radius: 100px;
     width: 140px;
 
@@ -16,12 +16,6 @@
       }
     }
 
-    @media print {
-      & {
-        display: none;
-      }
-    }
-
     transition: transform map_get($vars, $transition-time),
       opacity map_get($vars, $transition-time),
       background-color map_get($vars, $transition-time);

src/page/background/background.ts

@@ -9,7 +9,11 @@ export class PageBackground extends PageElement {
   private readonly blobs: Array<Blob> = [];
   private readonly blobSpacing = 350;
 
-  public constructor(private start: PageElement, private end: PageElement) {
+  public constructor(
+    private readonly start: PageElement,
+    private readonly inBetween: Array<PageElement>,
+    private readonly end: PageElement
+  ) {
     super();
     Blob.initialize(10, 30, 5);
   }
@@ -35,7 +39,7 @@ export class PageBackground extends PageElement {
   }
 
   private resize(parent: PageElement, heightChange?: number) {
-    const siblings: Array<HTMLElement> = PageBackground.getSiblings(parent);
+    const siblings: Array<HTMLElement> = this.getSiblings();
 
     const width = document.body.clientWidth;
     let height = sum(siblings.map(getHeight));
@@ -72,9 +76,7 @@ export class PageBackground extends PageElement {
     });
   }
 
-  private static getSiblings(parent: PageElement): Array<HTMLElement> {
-    return Array.prototype.slice
-      .call(parent.element.children)
-      .filter((e: HTMLElement) => !e.classList.contains('background-element'));
+  private getSiblings(): Array<HTMLElement> {
+    return [this.start, ...this.inBetween, this.end].map(e => e.element);
   }
 }

src/page/index.ts

@@ -8,16 +8,15 @@ import { ContainerPage } from '../framework/container-page';
 
 export const create = ({ header, timeline, footer }: Portfolio) => {
   const pageHeader = new PageHeader(header);
+  const pageTimeline = new PageTimeline(timeline);
   const pageFooter = new PageFooter(footer);
 
   new ContainerPage(document.body, [
     new PageImageViewer(),
-    new ContainerPage(document.body.querySelector('.main'), [
-      pageHeader,
-      new PageTimeline(timeline),
-      pageFooter,
-      new PageBackground(pageHeader, pageFooter),
-    ]),
+    pageHeader,
+    pageTimeline,
+    pageFooter,
+    new PageBackground(pageHeader, [pageTimeline], pageFooter),
   ]).setAsMain();
 
   addSupportForTabNavigation();