diff --git a/docs/assets/index-thumbnail.png b/docs/assets/index-thumbnail.png
deleted file mode 100644
index 4270c8f..0000000
Binary files a/docs/assets/index-thumbnail.png and /dev/null differ
diff --git a/docs/assets/index-thumbnail.webp b/docs/assets/index-thumbnail.webp
new file mode 100644
index 0000000..4c0f8fd
Binary files /dev/null and b/docs/assets/index-thumbnail.webp differ
diff --git a/docs/index.md b/docs/index.md
index 9f11949..1016149 100644
--- a/docs/index.md
+++ b/docs/index.md
@@ -61,7 +61,7 @@ hide:
         width: 100%;
         height: 100%;
         background-color: var(--md-default-bg-color);
-        background-image: url(/assets/index-thumbnail.png);
+        background-image: url(/assets/index-thumbnail.webp);
         background-size: cover;
         background-position: center;
         background-repeat: no-repeat;