fix: background doesn't default to black

src/App.svelte

@@ -2,6 +2,7 @@
   import SvgContent from "./components/SVGContent.svelte";
 
   function setBackground(ev: CustomEvent<string>) {
+    console.debug(`Setting background color to "${ev.detail}"`)
     document.body.style.background = ev.detail;
   }
 </script>
@@ -15,7 +16,6 @@
     html,
     body {
       overflow: hidden;
-      background: black;
     }
 
     html,