style: 調整關閉按鈕更靠近右上角

- 調整 top 從 20px 到 10px
- 添加負邊距讓按鈕更貼近角落
- 同步調整手機版樣式

Author: yulin0629

index.html

@@ -8,7 +8,7 @@
     <meta http-equiv="Expires" content="0">
     <meta name="theme-color" content="#000000">
     <title>GitHub Copilot 教學專案</title>
-    <link rel="stylesheet" href="style.css?v=20250603002">
+    <link rel="stylesheet" href="style.css?v=20250603003">
     <script src="https://cdn.jsdelivr.net/npm/marked/marked.min.js"></script>
     <script src="https://cdn.jsdelivr.net/npm/qrcodejs@1.0.0/qrcode.min.js"></script>
 </head>
@@ -352,6 +352,6 @@ <h3 style="font-size: 1.25rem; font-weight: 600; color: #1d1d1f; margin-bottom:
         </div>
     </div>
 
-    <script src="script.js?v=20250603002"></script>
+    <script src="script.js?v=20250603003"></script>
 </body>
 </html>

style.css

@@ -661,10 +661,12 @@ body {
 
 .markdown-close {
     position: sticky;
-    top: 20px;
+    top: 10px;
     float: right;
     margin-left: 20px;
     margin-bottom: 20px;
+    margin-top: -10px;
+    margin-right: -10px;
     width: 36px;
     height: 36px;
     cursor: pointer;
@@ -718,8 +720,9 @@ body {
 
 @media (max-width: 768px) {
     .markdown-close {
-        top: 20px;
-        right: 15px;
+        top: 5px;
+        margin-right: -5px;
+        margin-top: -5px;
         width: 32px;
         height: 32px;
         border-radius: 16px;