flashing text under content editor webpart

Hello all:

I want to have a flashing text on the Sharepoint 2010 site for the user when the list is under maintenance. For example: when the user logs in he should see flashinf text in bold red " DO NOT UPDATE THE LIST".

I was thinking of using CEWP by adding HTML / CSS code in it. But could not find a better solution.

Can you please suggest me on how can I acheive this task.

Thanks in advance.