diff --git a/csst_dfs_api/ifs/level1.py b/csst_dfs_api/ifs/level1.py
index 77e7821441eb3d5c140645c36316afa072025348..907f7fede4ce29518dbafc982d6c0f293a2ba3e2 100644
--- a/csst_dfs_api/ifs/level1.py
+++ b/csst_dfs_api/ifs/level1.py
@@ -3,7 +3,7 @@ from ..common.delegate import Delegate
 
 class Level1DataApi(object):
     """
-    Level1 Data Operation Class
+    IFS Level1 Data Operation Class
     """
     def __init__(self):
         self.pymodule = Delegate().load(sub_module = "ifs")
@@ -13,9 +13,9 @@ class Level1DataApi(object):
         ''' retrieve level1 records from database
 
         :param kwargs: Parameter dictionary, key items support:
-            raw_id: [int]
-            data_type: [str]
-            obs_type: [str]
+            raw_id: [int],
+            data_type: [str],
+            obs_type: [str],
             create_time : (start, end),
             qc1_status : [int],
             prc_status : [int],
diff --git a/docs/source/_static/csst_arch-API.jpg b/docs/source/_static/csst_arch-API.jpg
new file mode 100644
index 0000000000000000000000000000000000000000..484344588d5ebf76ca4122a6872058d2c1ce3512
Binary files /dev/null and b/docs/source/_static/csst_arch-API.jpg differ
diff --git a/docs/source/api.rst b/docs/source/api.rst
new file mode 100644
index 0000000000000000000000000000000000000000..f99fe36a3137ea7fd54571cabe97ec1ef1f6eb44
--- /dev/null
+++ b/docs/source/api.rst
@@ -0,0 +1,16 @@
+****************************************
+API
+****************************************
+
+.. toctree::
+   :maxdepth: 2
+
+   rst/csst_dfs_api.cpic
+   rst/csst_dfs_api.facility
+   rst/csst_dfs_api.hstdm
+   rst/csst_dfs_api.ifs
+   rst/csst_dfs_api.mci
+   rst/csst_dfs_api.msc
+
+
+
diff --git a/docs/source/changelog.rst b/docs/source/changelog.rst
new file mode 100644
index 0000000000000000000000000000000000000000..d416c746aab40d47c771c3e0a3202318e3ceeead
--- /dev/null
+++ b/docs/source/changelog.rst
@@ -0,0 +1,7 @@
+********************
+Change log
+********************
+
+0.0.1
+-----
+- C3 pipeline
\ No newline at end of file
diff --git a/docs/source/conf.py b/docs/source/conf.py
index 046201f27ba630f196c2a0217ff9da881d35bd1e..205a8fdc183c7f793cc175bba2669ff9f9d4f1bd 100644
--- a/docs/source/conf.py
+++ b/docs/source/conf.py
@@ -81,7 +81,7 @@ pygments_style = None
 # The theme to use for HTML and HTML Help pages.  See the documentation for
 # a list of builtin themes.
 #
-html_theme = 'classic'
+html_theme = 'sphinx_rtd_theme'
 
 # Theme options are theme-specific and customize the look and feel of a theme
 # further.  For a list of options available for each theme, see the
diff --git a/docs/source/index.rst b/docs/source/index.rst
index ec97e2ca08ee413701343c77ae6d036f3bd27a58..2b1cc44c4afcddf7991721a1774abfd97c116b5d 100644
--- a/docs/source/index.rst
+++ b/docs/source/index.rst
@@ -1,39 +1,16 @@
-.. CSST DFS API documentation master file, created by
-   sphinx-quickstart on Thu Jun 10 08:55:39 2021.
-   You can adapt this file completely to your liking, but it should at least
-   contain the root `toctree` directive.
+****************************************
+Welcome to CSST-DFS-API's documentation!
+****************************************
 
-Welcome to CSST DFS API's documentation!
-========================================
-
-This package provides APIs to access CSST's files and databases.
-
-Installation
-================
-
-This library can be installed with the following command: 
-
-.. code-block:: c
-
-   git clone https://github.com/astronomical-data-processing/csst-dfs-api.git
-   cd csst-dfs-api
-   pip install -r requirements.txt
-   python setup.py install 
-
-* NOTE: This library is heavily under coding, if any bugs occur, firstly you should try to update codes and install again like:
-
-.. code-block:: c
-
-   git pull
-   pip install -r requirements.txt
-   python setup.py install 
-
-APIs
-=====================
 .. toctree::
-   :maxdepth: 4
-
-   rst/modules
+   :maxdepth: 2
+   :caption: Contents:
+
+   introduction
+   installation
+   usage
+   api
+   changelog
 
 Indices and tables
 ==================
diff --git a/docs/source/installation.rst b/docs/source/installation.rst
new file mode 100644
index 0000000000000000000000000000000000000000..2912ebfb5418d5e39f85b417e7b0465d53af72f1
--- /dev/null
+++ b/docs/source/installation.rst
@@ -0,0 +1,28 @@
+********************
+Installation
+********************
+
+Installation
+==============
+
+This library can be installed with the following command: 
+
+.. code-block:: console
+
+   $ git clone https://github.com/astronomical-data-processing/csst-dfs-api.git
+   $ cd csst-dfs-api
+   $ pip install -r requirements.txt
+   $ python setup.py install 
+
+Upgrade
+==============
+
+* NOTE: This library is heavily under coding, if any bugs occur, firstly you should try to update codes and install again like:
+
+.. code-block:: console
+
+   $ git pull
+   $ pip install -r requirements.txt
+   $ python setup.py install 
+
+This is the recommended installation method and will install the latest release.
diff --git a/docs/source/introduction.rst b/docs/source/introduction.rst
new file mode 100644
index 0000000000000000000000000000000000000000..2b388329534162a88c162272045fb1f4e62015b0
--- /dev/null
+++ b/docs/source/introduction.rst
@@ -0,0 +1,5 @@
+************
+Introduction
+************
+
+This package provides APIs to access CSST's files and databases.
\ No newline at end of file
diff --git a/docs/source/usage.rst b/docs/source/usage.rst
new file mode 100644
index 0000000000000000000000000000000000000000..6a4ce72bb527baf0a46eb468dfb3b85aa7bc2bde
--- /dev/null
+++ b/docs/source/usage.rst
@@ -0,0 +1,18 @@
+********************
+Usage
+********************
+
+Common
+==============
+
+
+Facility
+==============
+
+
+MSC
+==============
+
+
+IFS
+==============