diff --git a/source/_static/css/custom.css b/source/_static/css/custom.css
new file mode 100644
index 0000000..7f4bc84
--- /dev/null
+++ b/source/_static/css/custom.css
@@ -0,0 +1,3 @@
+.wy-nav-content {
+  max-width: 100%;
+}
diff --git a/source/conf.py b/source/conf.py
index 9e95b13..e011d58 100644
--- a/source/conf.py
+++ b/source/conf.py
@@ -23,5 +23,10 @@ language = 'fr'
 # -- Options for HTML output -------------------------------------------------
 # https://www.sphinx-doc.org/en/master/usage/configuration.html#options-for-html-output
 
-html_theme = 'alabaster'
+html_theme = "sphinx_rtd_theme"
+# These folders are copied to the documentation's HTML output
 html_static_path = ['_static']
+
+# These paths are either relative to html_static_path
+# or fully qualified paths (eg. https://...)
+html_style = 'css/custom.css'