#atto_managefiles_manageform #id_deletefileshdr {
    display: none;
}

#atto_managefiles_manageform.has-unused-files #id_deletefileshdr {
    display: block;
}

#atto_managefiles_manageform #id_missingfileshdr {
    display: none;
}

#atto_managefiles_manageform.has-missing-files #id_missingfileshdr {
    display: block;
}