feat: add fullscreen mode to Go component

Adds a fullscreen toggle button that expands the component preview to fill the viewport while keeping all chrome (tabs, footer). Pressing Escape or clicking the button again exits fullscreen. Includes iOS Safari safe area support and smooth enter animation.

Author: Huxpro

src/example-preview/components/index.module.scss

@@ -237,6 +237,40 @@
   }
 }
 
+.box-fullscreen {
+  position: fixed;
+  top: 0;
+  left: 0;
+  right: 0;
+  bottom: 0;
+  z-index: 9999;
+  height: 100vh;
+  height: 100dvh;
+  width: 100vw;
+  border-radius: 0;
+  border: none;
+  padding:
+    env(safe-area-inset-top, 0px) env(safe-area-inset-right, 0px)
+    env(safe-area-inset-bottom, 0px) env(safe-area-inset-left, 0px);
+  animation: fullscreen-enter 0.15s ease-out;
+
+  @media (max-width: 600px) {
+    height: 100vh;
+    height: 100dvh;
+  }
+}
+
+@keyframes fullscreen-enter {
+  from {
+    opacity: 0.9;
+    transform: scale(0.98);
+  }
+  to {
+    opacity: 1;
+    transform: scale(1);
+  }
+}
+
 .code-view-comp {
   display: flex;
   align-items: center;

src/example-preview/components/index.tsx

@@ -28,7 +28,7 @@ import { SwitchSchema } from './switch-schema';
 import { PreviewImg } from './preview-img';
 import { ResizableContainer } from './resizable';
 
-import { IconGithub, IconCopyLink } from '../utils/icon';
+import { IconGithub, IconCopyLink, IconFullscreen, IconExitFullscreen } from '../utils/icon';
 import { tabScrollToTop } from '../utils/tool';
 import { useTreeController } from '../hooks/use-tree-controller';
 import type { SchemaOptionsData } from '../hooks/use-switch-schema';
@@ -143,10 +143,30 @@ export const ExampleContent: FC<ExampleContentProps> = ({
     };
   }, [previewImage, currentEntry, defaultWebPreviewFile]);
   const [tmpCurrentFileName, setTmpCurrentFileName] = useState('');
+  const [isFullscreen, setIsFullscreen] = useState(false);
   const defaultI18n = (key: string) => DEFAULT_I18N[key] || key;
   const t = useI18nHook ? useI18nHook() : defaultI18n;
   const lang = useLangHook ? useLangHook() : 'en';
 
+  useEffect(() => {
+    if (isFullscreen) {
+      const originalOverflow = document.body.style.overflow;
+      document.body.style.overflow = 'hidden';
+
+      const handleEscape = (e: KeyboardEvent) => {
+        if (e.key === 'Escape') {
+          setIsFullscreen(false);
+        }
+      };
+      document.addEventListener('keydown', handleEscape);
+
+      return () => {
+        document.body.style.overflow = originalOverflow;
+        document.removeEventListener('keydown', handleEscape);
+      };
+    }
+  }, [isFullscreen]);
+
   const getContainer = () => containerRef.current as HTMLDivElement;
   const onFileSelect = (v: string) => {
     setShowFileTree(false);
@@ -163,7 +183,7 @@ export const ExampleContent: FC<ExampleContentProps> = ({
 
   const showCodeTab = entryData && entryData?.length > 1;
   return (
-    <div className={s.box}>
+    <div className={`${s.box} ${isFullscreen ? s['box-fullscreen'] : ''}`}>
       <div className={s.container} ref={containerRef}>
         <div className={s.content}>
           <div className={s['code-wrap']}>
@@ -415,6 +435,23 @@ export const ExampleContent: FC<ExampleContentProps> = ({
                 );
               }}
             />
+            <Button
+              theme="borderless"
+              icon={
+                isFullscreen ? (
+                  <IconExitFullscreen
+                    style={{ color: 'var(--semi-color-text-2)' }}
+                  />
+                ) : (
+                  <IconFullscreen
+                    style={{ color: 'var(--semi-color-text-2)' }}
+                  />
+                )
+              }
+              type="tertiary"
+              size="small"
+              onClick={() => setIsFullscreen((v) => !v)}
+            />
             {rightFooter}
           </Space>
         </div>

src/example-preview/utils/icon.tsx

@@ -39,6 +39,40 @@ export function IconGithub(props: SVGProps<SVGSVGElement>) {
   );
 }
 
+export function IconFullscreen(props: SVGProps<SVGSVGElement>) {
+  return (
+    <svg
+      xmlns="http://www.w3.org/2000/svg"
+      viewBox="0 0 24 24"
+      width="1em"
+      height="1em"
+      {...props}
+    >
+      <path
+        fill="currentColor"
+        d="M7 14H5v5h5v-2H7v-3zm-2-4h2V7h3V5H5v5zm12 7h-3v2h5v-5h-2v3zM14 5v2h3v3h2V5h-5z"
+      />
+    </svg>
+  );
+}
+
+export function IconExitFullscreen(props: SVGProps<SVGSVGElement>) {
+  return (
+    <svg
+      xmlns="http://www.w3.org/2000/svg"
+      viewBox="0 0 24 24"
+      width="1em"
+      height="1em"
+      {...props}
+    >
+      <path
+        fill="currentColor"
+        d="M5 16h3v3h2v-5H5v2zm3-8H5v2h5V5H8v3zm6 11h2v-3h3v-2h-5v5zm2-11V5h-2v5h5V8h-3z"
+      />
+    </svg>
+  );
+}
+
 export function IconCopyLink(props: SVGProps<SVGSVGElement>) {
   return (
     <svg