style(exam->device): adjust device area icon size to be larger on exam page

close #28

src/pages/exam/DeviceArea.tsx

@@ -18,10 +18,13 @@ const DeviceArea = ({ className }: { className?: string }) => {
   const tabletStatus = useSelector(
     (state: RootState) => state.deviceArea.tabletStatus
   );
+  const btnStyle = { width: '1.5rem', height: '1.5rem' };
+  //const classValue='m-1';
 
   return (
     <Flex justify="end" align="center" className={`w-full ${className}`}>
       <Button
+        style={btnStyle}
         icon={
           <ToolOutlined
             className={
@@ -38,6 +41,7 @@ const DeviceArea = ({ className }: { className?: string }) => {
         title={`手闸状态指示器: ${generatorStatus}`}
       />
       <Button
+        style={btnStyle}
         icon={
           <CameraOutlined
             className={
@@ -52,6 +56,7 @@ const DeviceArea = ({ className }: { className?: string }) => {
         title={`曝光指示器: ${exposureStatus}`}
       />
       <Button
+        style={btnStyle}
         icon={
           <TabletOutlined
             className={