GEDmatch noted the following on their site yesterday (March 5th);
Mar 5, 2017: Recommended use https://www.gedmatch.com to connect to the site for the next 4 hours. If you still are seeing a Chinese web page you may need to clear your cache on your browser and/or restart your browser. Mar 5, 2017: There was a domain service name (DNS) IP change - some users experienced between 0 and 4 hours of loss of service. During that time the old IP was assigned to a Chinese site so some users were under the impression the site had been hacked - that was not the case. Sorry for this disruption.
Mar 5, 2017: Recommended use https://www.gedmatch.com to connect to the site for the next 4 hours. If you still are seeing a Chinese web page you may need to clear your cache on your browser and/or restart your browser.
Mar 5, 2017: There was a domain service name (DNS) IP change - some users experienced between 0 and 4 hours of loss of service. During that time the old IP was assigned to a Chinese site so some users were under the impression the site had been hacked - that was not the case. Sorry for this disruption.
Everything should be back to normal now. If not, you may need to clear your browser cache and/or DNS cache. (This is different depending on the browser and operating system. Easiest bet for some users might be to simply reboot their computer.)