CSS add missing semicolons in Vim via regex - regex

Question

I'm cleaning up some CSS for our company and in many of the classes there are missing semicolons. I've tried a number of different ways to make this happen in Vim, but so far I haven't found a viable solution. Below is an example of one class that seems to be part of a theme in this file.
What I'm thinking... if there's a \w \s \{ || \w\; then don't return true. Otherwise if there's a \:\s\w and no ; at the end of a line then return true.
.ribbon_table,
.tabbed_interface_section_table,
table#monthview_table,
table#weekview_table_table {
border-collapse: collapse
}
.btn.active.focus,
.btn.active:focus,
.btn.focus,
.btn:active.focus,
.btn:active:focus,
.btn:focus,
a:focus,
button:focus,
form:focus,
input:focus,
select:focus,
textarea:focus {
outline: 0;
}
blockquote {
font-size: 14px;
border: 0;
}
.caret {
border-top-style: solid
}

Answer 1

I would do something like :g/\v^\s+\S+:.+[^;]$/norm A;.
In case you're unfamiliar with these commands, here's the vim documentation for :g (:global) and :norm (:normal).
:g :global E147 E148
:[range]g[lobal]/{pattern}/[cmd]
Execute the Ex command [cmd] (default ":p") on the
lines within [range] where {pattern} matches.
:norm[al][!] {commands} :norm :normal
Execute Normal mode commands {commands}. This makes
it possible to execute Normal mode commands typed on
the command-line. {commands} are executed like they
are typed. For undo all commands are undone together.
Execution stops when an error is encountered.
If the [!] is given, mappings will not be used.
Without it, when this command is called from a
non-remappable mapping (:noremap), the argument can
be mapped anyway.
{commands} should be a complete command. If
{commands} does not finish a command, the last one
will be aborted as if <Esc> or <C-C> was typed.
This implies that an insert command must be completed
(to start Insert mode, see :startinsert). A ":"
command must be completed as well. And you can't use
"Q" or "gQ" to start Ex mode.
The display is not updated while ":normal" is busy.
{commands} cannot start with a space. Put a count of
1 (one) before it, "1 " is one space.
The 'insertmode' option is ignored for {commands}.
This command cannot be followed by another command,
since any '|' is considered part of the command.
This command can be used recursively, but the depth is
limited by 'maxmapdepth'.
An alternative is to use :execute, which uses an
expression as argument. This allows the use of
printable characters to represent special characters.
Example:
:exe "normal \<c-w>\<c-w>"

Answer 2

On the example you gave, :%s/\(\w*:\s*\w*\)$/\1; works fine.
Since it is not very readable, let's add some details:
Look for a word \w*
Followed by a :
Followed by between 0 and n spaces \s*
Followed by a word \w*
Followed by the end of a line $
You save this whole expression (let's call it expr) using parenthesis \(expr\), and use it again in the second hand using \1.
Thus, you can add the missing ; using \1;.