28   var atRules = {};
36     matchCallback(tokens[i], atRules);
39   if (Object.keys(atRules).length === 0) {
43   markUsedAtRules(tokens, markCallback, atRules, context);
45   for (atRule in atRules) {
46     atRuleTokens = atRules[atRule];
56 function markUsedAtRules(tokens, markCallback, atRules, context) {  argument
57   var boundMarkCallback = markCallback(atRules);
66         markUsedAtRules(tokens[i][2], markCallback, atRules, context);
71 function matchCounterStyle(token, atRules) {  argument
76     atRules[match] = atRules[match] || [];
77     atRules[match].push(token);
81 function markCounterStylesAsUsed(atRules) {  argument
94         if (wrappedProperty.components[0].value[0][1] in atRules) {
95           delete atRules[property[2][1]];
101       if (property[1][1] == 'list-style-type' && property[2][1] in atRules) {
102         delete atRules[property[2][1]];
108 function matchFontFace(token, atRules) {  argument
119         atRules[match] = atRules[match] || [];
120         atRules[match].push(token);
127 function markFontFacesAsUsed(atRules) {  argument
147           if (normalizedMatch in atRules) {
148             delete atRules[normalizedMatch];
159           if (normalizedMatch in atRules) {
160             delete atRules[normalizedMatch];
168 function matchKeyframe(token, atRules) {  argument
173     atRules[match] = atRules[match] || [];
174     atRules[match].push(token);
178 function markKeyframesAsUsed(atRules) {  argument
195           if (component.value[j][1] in atRules) {
196             delete atRules[component.value[j][1]];
205           if (property[j][1] in atRules) {
206             delete atRules[property[j][1]];
214 function matchNamespace(token, atRules) {  argument
219     atRules[match] = atRules[match] || [];
220     atRules[match].push(token);
224 function markNamespacesAsUsed(atRules) {  argument
225   var namespaceRegex = new RegExp(Object.keys(atRules).join('\\\||') + '\\\|', 'g');
241         if (normalizedMatch in atRules) {
242           delete atRules[normalizedMatch];