I want to add a pulsing circle before the post title on my news site.

When I create a new post I want a check button.
If i checked it then there would show a pulsing circle before the title of the post.
If it`s unchecked then the pulsing circle is off, and the title is standard.

Anyone with an idea how i easy can fix this ?
Some CSS maybe ?

Most ideal is an automatic function for when the post is not the top post of my site anymore the pulsing circle is not showing.