How to set position of create schedule panel with function

I am using Toast UI Calendar for schedule task manager. My project is Laravel.

If I select left day and center day, it is shown all. But if I select right-end day, the create panel is cut by screen. So I want to show it in screen with functions supported in toast ui calendar witout css fixing.

Position of popup panel is set like below code...

popup_layer.style.left = e.guide.guideElements[e.guide.startCoord[1]].style.left;

These are screenshots:

from How to set position of create schedule panel with function