fix: 弹框从顶部开始显示，整个modal区域可滚动，内容不会被挤出屏幕

web/static/style.css

@@ -405,8 +405,10 @@ button {
     height: 100%;
     background: rgba(0,0,0,0.8);
     z-index: 1000;
-    align-items: center;
+    align-items: flex-start;
     justify-content: center;
+    overflow-y: auto;
+    padding: 20px;
 }
 
 .modal.active {
@@ -418,15 +420,17 @@ button {
     padding: 15px;
     border-radius: 10px;
     max-width: 800px;
-    max-height: 90vh;
-    overflow-y: auto;
     position: relative;
 }
 
 .settings-modal-content {
-    max-width: 550px;
-    max-height: 85vh;
-    overflow-y: auto;
+    max-width: 500px;
+}
+
+.settings-modal-content h2 {
+    margin-bottom: 10px;
+    padding-bottom: 8px;
+    border-bottom: 1px solid #eee;
 }
 
 .modal-close {