You need to set the dimension to the overlay part to make it 100% and also, if wanted, the inset to 0, to make it fully full size
vaadin-dialog::part(overlay) {
border-radius: unset;
width: 100vw;
height: 100vh;
/* for mobiles you need to take some more things into account, like keyboard and browser url, but this is optional and really just necessary for phones etc. */
/* height: calc(100svh - env(keyboard-inset-height));*/
}
vaadin-dialog {
/* also reduce the inset to 0, otherwise it is like 98% */
--vaadin-overlay-viewport-inset: 0;
}
vaadin-dialog.visualizer-dialog::part(overlay) {
border-radius: unset;
width: 100vw;
height: 100vh;
}
vaadin-dialog.visualizer-dialog {
/* for mobiles you need to take some more things into account, like keyboard and browser url, but this is optional and really just necessary for phones etc. */
/* height: calc(100svh - env(keyboard-inset-height));*/
* also reduce the inset to 0, otherwise it is like 98% */
--vaadin-overlay-viewport-inset: 0;
}