/* Calendar */
.calendar-container { flex: 1; display: flex; flex-direction: column; background: var(--surface-color); }
.calendar-header { display: flex; justify-content: space-between; align-items: center; padding: 15px 20px; border-bottom: 1px solid var(--border-color); }
.sticky-cal-header { position: sticky; top: 0; background: var(--surface-color); z-index: 100; box-shadow: 0 4px 6px -1px rgba(0,0,0,0.05); }
#cal-prev-btn, #cal-next-btn {
    z-index: 101;
    scroll-margin-top: 80px;
    position: relative;
}
.calendar-grid { display: grid; grid-template-columns: repeat(7, 1fr); gap: 1px; background: var(--border-color); border-bottom: 1px solid var(--border-color); }
.cal-cell { background: var(--surface-color); text-align: center; padding: 15px 0; font-size: 14px; display: flex; flex-direction: column; align-items: center; justify-content: center; position: relative; min-height: 60px; }
.cal-header-cell { background: var(--surface-hover); font-weight: 600; font-size: 12px; color: var(--text-muted); padding: 10px 0; min-height: auto; }
.cal-cell.cal-day_valid { cursor: pointer; color: var(--text-main); font-weight: bold; }
.cal-cell.cal-day_valid:active { background: var(--surface-hover); }
.cal-cell.cal-day_invalid { color: var(--border-color); cursor: default; }