How to set one CSS rule for two tags?

I would like to know how I can set one setting for two different classes.

To give an example:

.footer #one .flag li .drop_down form div{
    width: 80px;
    font-family: Arial, Helvetica, sans-serif;
    font-size: 11px;
    text-align: left;
    line-height: 1.5;
    color: #ccc;
    font-weight:bolder;
    margin-left: 30px;
}
.footer #two .flag li .drop_down form div{
    width: 80px;
    font-family: Arial, Helvetica, sans-serif;
    font-size: 11px;
    text-align: left;
    line-height: 1.5;
    color: #ccc;
    font-weight:bolder;
    margin-left: 30px;
}

Both rules have the same content. The difference is just the second tag. Is there a way to do something like this?

.footer >>>#one and #two<<<< .flag li .drop_down form div{
        width: 80px;
        font-family: Arial, Helvetica, sans-serif;
        font-size: 11px;
        text-align: left;
        line-height: 1.5;
        color: #ccc;
        font-weight:bolder;
        margin-left: 30px;
    }

Solution

Separate the selectors with a comma:

.footer #one .flag li .drop_down form div,
.footer #two .flag li .drop_down form div {
    /* Rules */
}

From the selectors level 3 spec:

A comma-separated list of selectors represents the union of all elements selected by each of the individual selectors in the list. (A comma is U+002C.) For example, in CSS when several selectors share the same declarations, they may be grouped into a comma-separated list. White space may appear before and/or after the comma.