After you close the Library window, the Elementor editor will open up, with the Popup settings panel appearing on the left.
BTW, this panel is always accessible through the bottom gear icon.
In the Layout tab, we’ll set the width of the popup to 700 pixels, and the height as ‘Fit to Content’. Our popup will be positioned to the center, both horizontally and vertically.
In the Style tab, we’ll set a solid yellow border, with a 35-pixel border radius, giving our popup a rounded look.
Popup settings also include additional settings, like showing the close button after a set time, automatically closing the popup, a switch to prevent the popup from closing, a switch to disable page scrolling and a switch for avoiding multiple popups. We won’t be using them here, but it’s handy to know in case you need them.