diff --git a/environment.yml b/environment.yml
index 157946e..e16b7c6 100644
--- a/environment.yml
+++ b/environment.yml
@@ -7,7 +7,7 @@ dependencies:
   - pip
   - pip:
     - jupyter-book==1.0.4post1
-    - quantecon-book-theme==0.14.0
+    - quantecon-book-theme==0.15.0
     - sphinx-tojupyter==0.6.0
     - sphinxext-rediraffe==0.3.0
     - sphinx-exercise==1.2.1
diff --git a/lectures/_config.yml b/lectures/_config.yml
index 5218016..99d16f7 100644
--- a/lectures/_config.yml
+++ b/lectures/_config.yml
@@ -38,6 +38,7 @@ sphinx:
     bibtex_reference_style: author_year
     suppress_warnings: ["mystnb.unknown_mime_type"]
     nb_merge_streams: true
+    exercise_style: solution_follow_exercise
     # myst-nb config
     nb_render_image_options:
       width: 80%