The setting @julian describes belongs to the browser (chrome/chromium in this case), not NodeBB.
If you're using chrome/chromium, press F12, then F1 to show the options. Check the option and keep the tools open while refreshing the page to ensure the cache is disabled.
probleam about stylesheet.css.
In China,we can't use google's service.can we not use the google font in website?or is there any other option?
From what I've read in the news, I'm amazed you still have the Internet at all...
Edit your lavender theme by going to less/whiteplum.less and removing
12 @import url(//fonts.googleapis.com/css?family=Raleway:100,300,700,900,500);
You could specify a font from another provider that isn't blocked, or specify your own with the custom css in admin control panel.
@song19891121 Have you tried using a Mirror CDN?
e.g. Add this to the custom header block in the ACP:
<link href='http://fonts.useso.com/css?family=Open+Sans:300,400,600&subset=latin,latin-ext' rel='stylesheet'>
Edit: You'd probably still get the error nonetheless, but at least the fonts will work? So maybe use this in conjunction with @a_5mith's suggestion.