No the website is not down.

TurboTax website - https://turbotax.intuit.com/

To access your current or prior year tax returns sign onto the TurboTax website with the User ID you used to create the account - https://myturbotax.intuit.com/

It says this 

Please see the following link for steps to troubleshoot blank screens.

https://ttlc.intuit.com/community/troubleshooting/help/troubleshoot-blank-screens-missing-buttons-or...

If that doesn't work, you may have to clear your cache and cookies. Please see the following instructions on how to clear your cache.

https://ttlc.intuit.com/community/troubleshooting/help/how-to-clear-your-cache/00/26135

See here for instructions on clearing your cookies.

https://ttlc.intuit.com/community/troubleshooting/help/how-do-i-delete-cookies/00/25978

You may also try using another browser.

If none of these resolve the issue, please contact Customer Support for further assistance.

https://ttlc.intuit.com/community/using-turbotax/help/what-is-the-turbotax-phone-number/00/25632