Replace the old flask theme with the sphinx_rtd_theme

docs/conf.py

@@ -18,7 +18,6 @@ import os
 # add these directories to sys.path here. If the directory is relative to the
 # documentation root, use os.path.abspath to make it absolute, like shown here.
 sys.path.insert(0, os.path.abspath('..'))
-sys.path.append(os.path.abspath('_themes'))
 
 # -- General configuration -----------------------------------------------------
 
@@ -28,7 +27,8 @@ sys.path.append(os.path.abspath('_themes'))
 # Add any Sphinx extension module names here, as strings. They can be extensions
 # coming with Sphinx (named 'sphinx.ext.*') or your custom ones.
 extensions = ['sphinx.ext.autodoc', 'sphinx.ext.viewcode', 'sphinx.ext.todo',
-              'sphinx.ext.intersphinx', 'sphinx.ext.inheritance_diagram']
+              'sphinx.ext.intersphinx', 'sphinx.ext.inheritance_diagram',
+              'sphinx_rtd_theme']
 
 # Add any paths that contain templates here, relative to this directory.
 templates_path = ['_templates']
@@ -97,12 +97,15 @@ pygments_style = 'sphinx'
 
 # The theme to use for HTML and HTML Help pages.  See the documentation for
 # a list of builtin themes.
-html_theme = 'flask'
+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
 # documentation.
-#html_theme_options = {}
+html_theme_options = {
+    'logo_only': True,
+    'style_nav_header_background': 'white',
+}
 
 # Add any paths that contain custom themes here, relative to this directory.
 html_theme_path = ['_themes']
@@ -116,7 +119,7 @@ html_theme_path = ['_themes']
 
 # The name of an image file (relative to this directory) to place at the top
 # of the sidebar.
-#html_logo = None
+html_logo = '_static/logo.png'
 
 # The name of an image file (within the static path) to use as favicon of the
 # docs.  This file should be a Windows icon file (.ico) being 16x16 or 32x32
@@ -128,6 +131,8 @@ html_theme_path = ['_themes']
 # so a file named "default.css" will overwrite the builtin "default.css".
 html_static_path = ['_static']
 
+html_css_files = ['custom_style.css']
+
 # If not '', a 'Last updated on:' timestamp is inserted at every page bottom,
 # using the given strftime format.
 #html_last_updated_fmt = '%b %d, %Y'