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to get the category slug of the category archive:

$cat_slug = get_category(get_query_var('cat'))->slug;

alternatively, to get the category ID of the category archive:

$cat_id = get_query_var('cat');

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)