Replace index.rst

source/cpic/index.rst

-CPIC
-====
+.. CpicImgSim documentation master file, created by
+   sphinx-quickstart on Wed May 10 02:19:25 2023.
+   You can adapt this file completely to your liking, but it should at least
+   contain the root `toctree` directive.
 
-CPIC simulation
\ No newline at end of file
+
+
+CPISM: CSST/CPI-C 观测图像仿真软件包
+=====================================================
+
+.. image:: ../logo.png
+   :scale: 40
+   :align: center
+   :alt: CPISM logo
+
+
+.. toctree::
+   :maxdepth: 1
+   :hidden:
+
+   程序安装 <installation>
+   使用说明 <tutorials>
+   代码说明 <cpism>
+
+
+
+Indices and tables
+==================
+
+* :ref:`genindex`
+* :ref:`modindex`
+* :ref:`search`