diff --git a/frontend/src/features/chat/components/ChatWindow.css b/frontend/src/features/chat/components/ChatWindow.css
index fd514d6..d9d1154 100644
--- a/frontend/src/features/chat/components/ChatWindow.css
+++ b/frontend/src/features/chat/components/ChatWindow.css
@@ -73,6 +73,35 @@
     color: #f3f4f6 !important; /* gray-100 */
 }
 
+.markdown-preview {
+    white-space: normal; /* Override pre-wrap to prevent ReactMarkdown's structural HTML newlines from stacking with CSS margins */
+    line-height: 1.5;
+}
+
+.markdown-preview > *:last-child {
+    margin-bottom: 0 !important;
+}
+
+.markdown-preview p {
+    margin-bottom: 0.6em;
+}
+
+.markdown-preview ul, .markdown-preview ol {
+    margin-bottom: 0.6em;
+    margin-top: 0.2em;
+    padding-left: 1.25em;
+}
+
+.markdown-preview li {
+    margin-bottom: 0.2em;
+}
+
+.markdown-preview h1, .markdown-preview h2, .markdown-preview h3, .markdown-preview h4 {
+    margin-top: 1em;
+    margin-bottom: 0.5em;
+    line-height: 1.25;
+}
+
 /* Force light text color on all nested elements in dark mode */
 .dark .assistant-message *,
 .dark .assistant-message p,
@@ -192,14 +221,18 @@
 .thought-panel blockquote {
     border-left: 2px solid rgba(99, 102, 241, 0.4) !important;
     background: rgba(99, 102, 241, 0.05) !important;
-    margin: 0.75rem 0 0.75rem 1rem !important;
-    padding: 0.6rem 0.8rem !important;
+    margin: 0.5rem 0 0.5rem 0.5rem !important;
+    padding: 0.4rem 0.6rem !important;
     border-radius: 0.5rem !important;
-    font-size: 0.7rem !important;
+    font-size: 0.75rem !important;
     line-height: 1.4 !important;
     color: #4f46e5 !important;
 }
 
+.thought-panel .markdown-preview p {
+    margin-bottom: 0.4em !important;
+}
+
 .dark .thought-panel blockquote {
     color: #818cf8 !important;
     background: rgba(129, 140, 248, 0.05) !important;