add logo of ip and ip ntework on first page

source/index.rst

@@ -26,4 +26,21 @@ Indices and tables
 
 .. only:: html
 
-   :download:`Latex version <_static/unix_course_for_sars-cov-2_sequence_analysis.pdf>`
+   :download:`Download the Latex version <_static/unix_course_for_sars-cov-2_sequence_analysis.pdf>`
+
+
+.. container:: twocol
+
+   .. container:: leftside
+
+      .. image:: _static/imgs/pasteur-network.png
+         :height: 80px
+         :align: left
+         :target: https://pasteur-network.org/
+
+   .. container:: rightside
+
+      .. image:: _static/imgs/institut_pasteur_logo_2020.png
+         :height: 60px
+         :align: right
+         :target: https://www.pasteur.fr/fr
\ No newline at end of file