diff --git a/src/lib/styles/feedback.css b/src/lib/styles/feedback.css
index a8676ab..a429e74 100644
--- a/src/lib/styles/feedback.css
+++ b/src/lib/styles/feedback.css
@@ -1666,6 +1666,10 @@ body { min-height: 100vh; }
 @media (min-width: 900px) {
 	.fb-participant {
 		grid-template-columns: 1fr 1fr;
+		/* Don't stretch the chat column to match a long form. Each column
+		   takes its own natural height; the chat column then caps itself
+		   to the viewport via .fb-participant__col--chat below. */
+		align-items: start;
 	}
 }
 
@@ -1700,12 +1704,24 @@ body { min-height: 100vh; }
 	}
 }
 
-/* Chat column — bubbles fill the column height, compose pinned at bottom. */
+/* Chat column — bubbles fill the column height, compose pinned at bottom.
+   The column always caps to the viewport so a long form on the left can't
+   stretch the chat into a 3000px tall scroll-soup. On desktop it sticks to
+   the top so it stays visible while the user scrolls down through the
+   form. On mobile it just caps below the form. */
 .fb-participant__col--chat {
 	background: var(--color-bg-primary);
 	border-radius: var(--radius-lg);
 	padding: var(--space-3);
 	min-height: 320px;
+	max-height: calc(100vh - 2rem);
+}
+
+@media (min-width: 900px) {
+	.fb-participant__col--chat {
+		position: sticky;
+		top: 1rem;
+	}
 }
 
 @media (max-width: 899px) {