css rollover help

[moscarda]

i want to apply a css style to thumbnail images so that when they are hovered over, they have a red inner stroke... is this possible...kind of like the rectangles on this site:

http://www.uxmag.com

[boxxertrumps]

you just make a new class thats like
tag {Style for not mouseovered}
tag:hover {style changes on mouseover}

[moscarda]

argh,
but what are the properties, i don't know enough about css
thanks in advance

[boxxertrumps]

tag:hover {border:1px solid red}
from what i can remember.
or .class:hover
depends on your site..