/*
 * The category axis duplicates the five study-level exam divisions.
 * Retain the underlying category values for REST, landing pages and analytics,
 * but never expose the category control as a second learner-facing "科目".
 * Applied before Core promotes visible advanced fields into basic settings.
 */
body.koutan-dojo-page #koutan-app .filter-group.question-field-filter:has(> #cat-select) {
    display: none !important;
}