diff --git a/docs/.vitepress/theme/components/VPIframe.vue b/docs/.vitepress/theme/components/VPIframe.vue
index 5b79a739..030d97bf 100644
--- a/docs/.vitepress/theme/components/VPIframe.vue
+++ b/docs/.vitepress/theme/components/VPIframe.vue
@@ -230,7 +230,7 @@ watch(
   position: fixed;
   z-index: 10;
   right: 32px;
-  top: calc(var(--vp-nav-height) + var(--vp-layout-top-height) + 32px);
+  top: calc(var(--vp-nav-height) + var(--vp-layout-top-height, 0px) + 32px);
   width: 330px;
   font-size: 16px;
   background: var(--vp-c-bg-alt);
@@ -360,7 +360,7 @@ watch(
   position: fixed;
   z-index: 10;
   right: 16px;
-  top: calc(var(--vp-nav-height) + var(--vp-layout-top-height) + 32px);
+  top: calc(var(--vp-nav-height) + var(--vp-layout-top-height, 0px) + 32px);
   width: 48px;
   height: 48px;
   background: var(--vp-c-bg-alt);