CSS attachment is causing green links instead of purple

[design]

I recently added

a:visited {
color: #4B0082;
text-decoration: none;
font-size:12px;
font-family:times new roman, arial, helvetica, sans-serif;
{

to my style sheet for visited links. I wanted it to be purple. At first the purple color code turned my links into green. I also tried the color code for violet, indigo, and other related colors of purple.

My source of color codes is from http://www.htmlhelp.com. See design elements. The last link for design elements is RGB color codes.

I want my unvisited to be blue and visited to be purple.

Please help me to fix this. Another message board suggested that the problem was with the semicolon. I added it in, but it made no difference.