Extract config defaults

src/config.js

@@ -0,0 +1,37 @@
+(() => {
+  const create = () => {
+    const defaultMessageConfig = {
+      durationMs: 4200,
+      position: { xPercent: 50, yPercent: 10 },
+      text: null,
+      colors: null,
+    };
+
+    const config = {
+      gravity: 1,
+      spawnIntervalMs: 520,
+      autoSpawn: true,
+      minChain: 3,
+      palette: ["#ff595e", "#ffca3a", "#8ac926", "#1982c4", "#6a4c93"],
+      ballRadius: 18,
+      ballShape: "circle",
+      link: {
+        stiffness: 0.85,
+        lengthScale: 1.05, // max stretch factor; slack below this
+        damping: 0.08,
+        lineWidth: 3,
+        rope: true,
+        renderType: "line",
+        maxLengthMultiplier: 3.1,
+      },
+      messages: { ...defaultMessageConfig },
+    };
+
+    return {
+      defaultMessageConfig: { ...defaultMessageConfig },
+      config: { ...config, link: { ...config.link }, messages: { ...config.messages } },
+    };
+  };
+
+  window.PhysilinksConfig = { create };
+})();