style(export): stack media defaults section

src/components/Export/ExportDefaultsSettingsForm.scss

@@ -393,10 +393,20 @@
       align-items: stretch;
     }
 
+    .media-setting-group {
+      grid-template-columns: 1fr;
+      gap: 10px;
+      align-items: stretch;
+    }
+
     .format-setting-group .form-control {
       justify-content: flex-start;
     }
 
+    .media-setting-group .form-control {
+      justify-content: flex-start;
+    }
+
     .format-grid {
       max-width: none;
       grid-template-columns: repeat(3, minmax(0, 1fr));

src/components/Export/ExportDefaultsSettingsForm.tsx

@@ -245,7 +245,7 @@ export function ExportDefaultsSettingsForm({
         }}
       />
 
-      <div className="form-group">
+      <div className="form-group media-setting-group">
         <div className="form-copy">
           <label>默认导出媒体内容</label>
           <span className="form-hint">控制图片、视频、语音、表情包的默认导出开关</span>