diff --git a/json_to_md.py b/json_to_md.py
index 55bcafc9..f2ae1f2c 100644
--- a/json_to_md.py
+++ b/json_to_md.py
@@ -61,14 +61,22 @@ def normalize_nodeid(nodeid):
     return None
 
 def get_details_block(summary, body, level=0, params_str=None):
-    prefix = "  " * level  # indentation pour lisibilité manuelle
-    if params_str:
-        summary += f" | parameters: [{params_str}]"
+    prefix = "┃ " * level  # une barre par niveau
+    inner_prefix = "┃ " * (level + 1)
 
-    return (f"{prefix}<details>\n"
-            f"{prefix}<summary>{summary}</summary>\n\n"
-            f"{body}\n"
-            f"{prefix}</details>\n\n")
+    if params_str and params_str.strip() != "{}":
+        summary += f" · params: [{params_str}]"
+
+    # Préfixe chaque ligne du body
+    body_lines = body.strip().splitlines()
+    indented_body = "\n".join(inner_prefix + line for line in body_lines)
+
+    return (
+        f"{prefix}<details>\n"
+        f"{prefix}<summary>{summary}</summary>\n\n"
+        f"{indented_body}\n\n"
+        f"{prefix}</details>\n\n"
+    )
 
 
 def make_test_block(test, status, emoji, level, runtime_params):