Where do I put the code?, for my borders? Options

[x3chrissyx3]

I have done this before, yet I've forgotten...
Where do you put the border codes, to have borders like I have shown in the attachment?

I've added it here:

CODE

.post {
margin: 0 16px 14px 29px;
padding: 0;
border-bottom: 2px solid #ffffff;
border-right: 2px soild #ffffff;
border-top: 2px solid #ffffff;
}

and here:
  #sidebar {
    padding: 7px 11px 0 14px;
    background: #000000;
    border-left: 2px solid #ffffff;
    border-top: 2px solid #ffffff;
    border-bottom: 2px solid #ffffff,
    border-right: 2px solid #fffffff;

and I know that's wrong, lol since it's not working.
Any idea on where to put it??