fix: bug

app/static/style.css

@@ -38,6 +38,11 @@ body {
   margin: 6px 0 0;
 }
 
+.backend-config {
+  margin: 8px 0 0;
+  line-height: 1.5;
+}
+
 .badge {
   font-size: 12px;
   font-weight: 700;
@@ -161,11 +166,130 @@ button:disabled {
   font-weight: 600;
 }
 
+.small {
+  font-size: 13px;
+  margin: 0 0 12px;
+}
+
+.flow-hint {
+  margin: 0 0 14px 18px;
+  padding: 0;
+  font-size: 13px;
+  line-height: 1.6;
+}
+
+.trace-wrap {
+  margin-top: 12px;
+  padding: 10px 12px;
+  border: 1px dashed var(--line);
+  border-radius: 10px;
+  background: #f9fbf9;
+}
+
+.trace-wrap summary {
+  cursor: pointer;
+  font-weight: 700;
+  color: var(--text);
+}
+
+.trace-badge {
+  margin-left: 8px;
+  font-size: 11px;
+  padding: 2px 8px;
+  border-radius: 999px;
+  font-weight: 700;
+}
+
+.trace-badge.is-ai {
+  background: #eaf7f0;
+  color: #0f5f3d;
+  border: 1px solid #cde6d7;
+}
+
+.trace-badge.is-fallback {
+  background: #fff4e6;
+  color: #9a3412;
+  border: 1px solid #fed7aa;
+}
+
+.body-split {
+  display: grid;
+  grid-template-columns: 1fr 1fr;
+  gap: 12px;
+  align-items: stretch;
+}
+
+.body-split textarea {
+  min-height: 280px;
+}
+
+.preview-panel {
+  display: flex;
+  flex-direction: column;
+  min-width: 0;
+}
+
+.markdown-preview {
+  flex: 1;
+  min-height: 280px;
+  max-height: 480px;
+  overflow: auto;
+  padding: 12px 14px;
+  border: 1px solid var(--line);
+  border-radius: 10px;
+  background: #fafcfb;
+  font-size: 14px;
+  line-height: 1.65;
+}
+
+.markdown-preview h2 {
+  font-size: 1.15rem;
+  margin: 1em 0 0.5em;
+  color: var(--accent-2);
+}
+
+.markdown-preview h3 {
+  font-size: 1.05rem;
+  margin: 0.9em 0 0.4em;
+}
+
+.markdown-preview p {
+  margin: 0.5em 0;
+}
+
+.markdown-preview ul,
+.markdown-preview ol {
+  margin: 0.4em 0 0.6em 1.2em;
+  padding: 0;
+}
+
+.markdown-preview li {
+  margin: 0.25em 0;
+}
+
+.trace-json {
+  margin: 10px 0 0;
+  padding: 10px;
+  max-height: 220px;
+  overflow: auto;
+  font-size: 11px;
+  line-height: 1.45;
+  background: #fff;
+  border-radius: 8px;
+  border: 1px solid var(--line);
+  white-space: pre-wrap;
+  word-break: break-word;
+}
+
 @media (max-width: 960px) {
   .layout {
     grid-template-columns: 1fr;
   }
 
+  .body-split {
+    grid-template-columns: 1fr;
+  }
+
   .topbar {
     align-items: flex-start;
     gap: 8px;