use flex for body

index.html

@@ -4,7 +4,7 @@
 <script src=/diffDOM.js></script>
 <script src=/springy.js></script>
 <script src=/src/index.js type=module></script>
-<div></div>
+<div class=wrapper></div>
 <aside>
   <a href="https://git.adrianheine.de/adrian/coding-precarity">git</a>
 </aside>

style.css

@@ -8,22 +8,27 @@
   src: url("/IMFePIsc29P.ttf");
 }
 
-
 body {
   background-color: #e1eef2;
   margin: 0;
   font-family: "Fell";
   hyphens: auto;
+  display: flex;
+  flex-direction: column;
+  height: 100%;
+  width: 100%;
 }
 
 .wrapper {
   max-width: 70em;
+  width: 100%;
   height: 100%;
   margin: 0 auto;
   background-color: #FFC63F;
   position: relative;
   box-sizing: border-box;
   padding: 20px;
+  flex: 1;
 }
 
 .items {