chore: adjust styles

apps/venus/src/app/index.tsx

@@ -235,7 +235,7 @@ const GitHub = (props: { center?: boolean; flat?: boolean }) => {
             startIcon={<GitHubIcon />}
             size="lg"
         >
-            Check GitHub
+            {props.center ? 'Check ' : ''}GitHub
         </Button>
     );
 };

libs/components/layout/src/header/LayoutHeader.tsx

@@ -24,7 +24,7 @@ export const LayoutHeader = () => {
     const warningTips = useMemo(() => {
         if (!fsApiSupported()) {
             return 'Your browser does not support the local storage feature, please upgrade to the latest version of Chrome or Edge browser';
-        } else if (isLocalWorkspace) {
+        } else if (!isLocalWorkspace) {
             return 'You are in DEMO mode. Changes will NOT be saved unless you SYNC TO DISK';
         } else {
             return 'AFFiNE is under active development and the current version is UNSTABLE. Please DO NOT store information or data';