Source:
.foo { line-height: 150px; font-size: 24px; clear: both; }
vim magic here, probably something visual selection based
R
:s/\([{;]\)\s*/\1\r/g | '[+1,']sort | '[,']join
Split the line on { or ; to get each rule into a separate line, :sort them (omitting the first line containing the CSS definition), then join them back together.
{
;
:sort