diff --git a/scss/partials/ai-modal.scss b/scss/partials/ai-modal.scss
index 8b365e2..2586111 100644
--- a/scss/partials/ai-modal.scss
+++ b/scss/partials/ai-modal.scss
@@ -48,6 +48,7 @@
 
         :first-child[id^="tiny_ai_"] {
             display: flex;
+            flex-grow: 1;
             padding: 8px 24px 0px 24px;
             flex-direction: column;
 
diff --git a/styles.css b/styles.css
index c895106..0b3c333 100644
--- a/styles.css
+++ b/styles.css
@@ -231,6 +231,7 @@
 }
 .tiny_ai-modal--dialog [data-region=body] :first-child[id^=tiny_ai_] {
   display: flex;
+  flex-grow: 1;
   padding: 8px 24px 0px 24px;
   flex-direction: column;
 }
diff --git a/templates/components/moodle-modal-body-optimize.mustache b/templates/components/moodle-modal-body-optimize.mustache
index 62d46f9..2ae4e64 100644
--- a/templates/components/moodle-modal-body-optimize.mustache
+++ b/templates/components/moodle-modal-body-optimize.mustache
@@ -31,7 +31,7 @@ Context variables required for this template:
 Example context (json):
 {}
 }}
-<div id="tiny_ai_optimize_{{uniqid}}" data-tiny_instance_uniqid={{tinyinstanceuniqid}}>
+<div id="tiny_ai_optimize_{{uniqid}}" data-tiny_instance_uniqid={{tinyinstanceuniqid}} class="flex-grow-1">
     {{> tiny_ai/components/ai-textarea }}
 </div>
 {{#js}}