fix rst subheadings
diff --git a/docs/source/index.rst b/docs/source/index.rst
index 332dad6..1066c60 100644
--- a/docs/source/index.rst
+++ b/docs/source/index.rst
@@ -165,6 +165,7 @@
Caravel Integration
===================
+----------------
Repo Integration
----------------
@@ -189,6 +190,7 @@
The symbolic links are automatically set when you run ``make install``.
+-------------------
Verilog Integration
-------------------
@@ -224,6 +226,7 @@
</p>
+-------------------
Layout Integration
-------------------
@@ -323,6 +326,7 @@
Hardening the User Project using OpenLane
==========================================
+---------------------
OpenLane Installation
---------------------
@@ -342,6 +346,7 @@
to
`README <https://github.com/The-OpenROAD-Project/OpenLane#setting-up-openlane>`__.
+-----------------
Hardening Options
-----------------
@@ -376,7 +381,7 @@
For more details on hardening macros using openlane, refer to `README <https://github.com/The-OpenROAD-Project/OpenLane/blob/master/docs/source/hardening_macros.md>`__.
-
+-----------------
Running OpenLane
-----------------
