diff --git a/index.html b/index.html
index fc164582..3fcf98d7 100644
--- a/index.html
+++ b/index.html
@@ -13,7 +13,7 @@
     <section class="container mb-5">
         <div class="card bg-primary text-white text-center">
             <div class="card-body">
-                <h5 class="card-title fs-3">THIS IS A SANDBOX</h5>
+                <h5 class="card-title fs-3"><b>THIS IS A SANDBOX</b></h5>
                 <p class="card-text">If you want to access the Infectious Diseases Toolkit, please go to <a class="link-body-emphasis" href="https://www.infectious-diseases-toolkit.org/"><b>Infectious Diseases Toolkit</b></a>. This is a sandbox for experimenting. Its content can be meaningless and gets periodically modified and deleted without warning.</p>
             </div>
         </div>