Add occasional longer stretch pauses (10-20s)

static/app.js

@@ -270,6 +270,13 @@ function calculateDelay() {
     const round = state.round;
     const { initialMin, initialMax, stretchFactor, maxDelay } = CONFIG.delay;
 
+    // 20% chance of a longer "stretch pause" (10-20 seconds)
+    if (Math.random() < 0.2 && round > 1) {
+        const longDelay = 10 + Math.random() * 10; // 10-20 seconds
+        return Math.round(longDelay * 10) / 10;
+    }
+
+    // Normal progressive delay
     const factor = Math.pow(stretchFactor, round - 1);
     const min = Math.min(initialMin * factor, maxDelay * 0.5);
     const max = Math.min(initialMax * factor, maxDelay);