diff --git a/docs/guide/theme/custom.css b/docs/guide/theme/custom.css
index 0a0dafb6..b9a29137 100644
--- a/docs/guide/theme/custom.css
+++ b/docs/guide/theme/custom.css
@@ -69,6 +69,7 @@ code, pre, .hljs {
     padding: 6px 0;
     border-radius: 4px;
     transition: color 0.15s;
+    font-size: 1rem;
 }
 
 .sidebar ol.chapter li a:hover {