@media (max-width: 600px) {
 .course-block .course-period { grid-template-columns: minmax(0, 1fr) 36px minmax(0, 1fr); column-gap: 12px; }
}
@media (max-width: 350px) {
 .course-block .course-period { grid-template-columns: minmax(0, 1fr) 28px minmax(0, 1fr); column-gap: 8px; }
}