code: function statement(toks, i, n, handler) {
      if (i < n) {
        var tok = toks[i];
        if (tok.charAt(0) === '@') {
          return atrule(toks, i, n, handler, true);
        } else {
          return ruleset(toks, i, n, handler);
        }
      } else {
        return i;
      }
    }
docs: statement   : ruleset | at-rule;