diff --git a/_locales/en/messages.json b/_locales/en/messages.json
index f1a1c96..299a1aa 100644
--- a/_locales/en/messages.json
+++ b/_locales/en/messages.json
@@ -164,9 +164,6 @@
    "langKorean": {
       "message": "한국어"
    },
-   "fullscreenBtn": {
-      "message": "Fullscreen"
-   },
    "tipFullscreen": {
       "message": "Open fullscreen editor"
    },
diff --git a/_locales/ja/messages.json b/_locales/ja/messages.json
index 20aafec..8a72cc1 100644
--- a/_locales/ja/messages.json
+++ b/_locales/ja/messages.json
@@ -164,13 +164,10 @@
   "langKorean": {
     "message": "한국어"
   },
-  "fullscreenBtn": {
-    "message": "全画面"
-  },
   "tipFullscreen": {
     "message": "全画面で編集"
   },
   "tipResize": {
     "message": "ドラッグで拡大/縮小（最小：初期サイズ）"
   }
-}
+}
\ No newline at end of file
diff --git a/_locales/ko/messages.json b/_locales/ko/messages.json
index da14da3..882b9d7 100644
--- a/_locales/ko/messages.json
+++ b/_locales/ko/messages.json
@@ -158,19 +158,16 @@
   "langChineseSimplified": {
     "message": "简体中文"
   },
-  "langJapanese": {
+    "langJapanese": {
     "message": "日本語"
   },
   "langKorean": {
     "message": "한국어"
   },
-  "fullscreenBtn": {
-    "message": "전체화면"
-  },
   "tipFullscreen": {
     "message": "전체화면 편집"
   },
   "tipResize": {
     "message": "드래그로 확대/축소(최소: 기본 크기)"
   }
-}
+}
\ No newline at end of file
diff --git a/_locales/zh_CN/messages.json b/_locales/zh_CN/messages.json
index 6f04e1d..8a95351 100644
--- a/_locales/zh_CN/messages.json
+++ b/_locales/zh_CN/messages.json
@@ -164,9 +164,6 @@
    "langKorean": {
       "message": "한국어"
    },
-   "fullscreenBtn": {
-      "message": "全屏"
-   },
    "tipFullscreen": {
       "message": "全屏编辑"
    },
diff --git a/css/main.css b/css/main.css
index 4e22fb6..6a9b183 100644
--- a/css/main.css
+++ b/css/main.css
@@ -51,9 +51,17 @@ a{color: #555;}
 .memo-editor{
     position: relative;
     resize: none;
-    overflow: hidden;
+    overflow: visible;
     box-sizing: border-box;
-    contain: layout paint;
+    contain: layout;
+}
+
+.memo-editor-header{
+    position: sticky;
+    top: .5rem;
+    z-index: 3;
+    height: 0;
+    display: block;
 }
 
 #editor-resize-handle{
@@ -79,6 +87,10 @@ a{color: #555;}
 .body.fullscreen #editor-resize-handle{
     display: none;
 }
+
+.body.fullscreen #fullscreen{
+    display: none;
+}
 .random-item{
     border: 1px solid rgb(229,231,235);
     color: #666;
@@ -99,19 +111,26 @@ a{color: #555;}
 .btns-container{text-align:right;}
 .memo-editor #fullscreen{
     position: absolute;
-    right: .5rem;
-    top: .5rem;
+    right: 0;
+    top: 0;
     z-index: 2;
     border: 1px solid rgb(229,231,235);
     border-radius: .25rem;
     background-color: rgb(255,255,255);
     color: #666;
     font-size: .75rem;
-    line-height: 1.5rem;
-    padding: 0 .4rem;
+    line-height: 1;
+    padding: .25rem;
+    display: inline-flex;
+    align-items: center;
+    justify-content: center;
     cursor: pointer;
     opacity: .9;
 }
+
+.memo-editor #fullscreen svg{
+    display: block;
+}
 .memo-editor #fullscreen:hover{
     opacity: 1;
     background-color: rgb(243,244,246);
@@ -132,8 +151,10 @@ a{color: #555;}
 }
 
 .common-editor-inputer{
-    padding-top: 1.8rem;
-    padding-right: 3.2rem;
+    padding-right: 1.5rem;
+    height: auto;
+    display: block;
+    box-sizing: border-box;
 }
 
 .body.fullscreen{
diff --git a/js/i18n.js b/js/i18n.js
index 870738f..11648ad 100644
--- a/js/i18n.js
+++ b/js/i18n.js
@@ -86,7 +86,8 @@ function applyStaticI18n() {
 	setText('lockPublic', 'lockPublic')
 
 	setText('content_submit_text', 'submitBtn')
-	setText('fullscreen', 'fullscreenBtn')
+	const fullscreen = document.getElementById('fullscreen')
+	if (fullscreen) fullscreen.setAttribute('aria-label', t('tipFullscreen'))
 
 	setPlaceholder('hideInput', 'placeHideInput')
 	setPlaceholder('showInput', 'placeShowInput')
diff --git a/popup.html b/popup.html
index f2df32e..b529bf0 100644
--- a/popup.html
+++ b/popup.html
@@ -51,7 +51,13 @@
     </div>
 
     <div class="memo-editor">
-      <button id="fullscreen" class="action-btn" type="button"></button>
+      <div class="memo-editor-header">
+        <button id="fullscreen" class="action-btn" type="button" aria-label="">
+          <svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-fullscreen" viewBox="0 0 16 16">
+            <path d="M1.5 1a.5.5 0 0 0-.5.5v4a.5.5 0 0 1-1 0v-4A1.5 1.5 0 0 1 1.5 0h4a.5.5 0 0 1 0 1zM10 .5a.5.5 0 0 1 .5-.5h4A1.5 1.5 0 0 1 16 1.5v4a.5.5 0 0 1-1 0v-4a.5.5 0 0 0-.5-.5h-4a.5.5 0 0 1-.5-.5M.5 10a.5.5 0 0 1 .5.5v4a.5.5 0 0 0 .5.5h4a.5.5 0 0 1 0 1h-4A1.5 1.5 0 0 1 0 14.5v-4a.5.5 0 0 1 .5-.5m15 0a.5.5 0 0 1 .5.5v4a1.5 1.5 0 0 1-1.5 1.5h-4a.5.5 0 0 1 0-1h4a.5.5 0 0 0 .5-.5v-4a.5.5 0 0 1 .5-.5"/>
+          </svg>
+        </button>
+      </div>
       <textarea
         class="common-editor-inputer"
         rows="4"