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It ought to. Specificity is almost likely the culprit.

All rulesets are afforded a ‘number’ that represents their ‘Weight’ or specificity; the specificness of that rules properties over another, it’s calculated from the selectors which have various numbers assigned them.

To test try adding in antecedent selectors – ancestors or parents of the selector being styled until you find control, so :

body#bp-default a , body#bp-default #container h2 a:hover

Play around, add further selectors to the mix to increase the weight if necessary, see if that gives you control, then you will know what the issue is