diff --git a/css/html_bubble_chat_style.css b/css/html_bubble_chat_style.css
index fff10fd..77090b6 100644
--- a/css/html_bubble_chat_style.css
+++ b/css/html_bubble_chat_style.css
@@ -2,7 +2,7 @@
     margin-left: auto;
     margin-right: auto;
     max-width: 800px;
-    height: 66.67vh;
+    height: calc(100vh - 300px);
     overflow-y: auto;
     padding-right: 20px;
     display: flex;
diff --git a/css/html_cai_style.css b/css/html_cai_style.css
index aeb6ce1..04a9d90 100644
--- a/css/html_cai_style.css
+++ b/css/html_cai_style.css
@@ -2,7 +2,7 @@
     margin-left: auto;
     margin-right: auto;
     max-width: 800px;
-    height: 66.67vh;
+    height: calc(100vh - 300px);
     overflow-y: auto;
     padding-right: 20px;
     display: flex;
diff --git a/css/html_instruct_style.css b/css/html_instruct_style.css
index 96ffedf..dc7f5a0 100644
--- a/css/html_instruct_style.css
+++ b/css/html_instruct_style.css
@@ -2,7 +2,7 @@
     margin-left: auto;
     margin-right: auto;
     max-width: 800px;
-    height: 66.67vh;
+    height: calc(100vh - 300px);
     overflow-y: auto;
     padding-right: 20px;
     display: flex;