@flexilla/flexilla/dist/dropdown.css

A set of unstyled interactive components for building interactive, and customizable user interfaces. Open-Source

[data-fx-popper] {
    position: fixed;
    left    : var(--fx-popper-placement-x, 0px);
    top     : var(--fx-popper-placement-y, 0px);
}

[data-fx-dropdown] [data-fx-popper] {
    visibility: hidden;
}

[data-fx-dropdown][data-state=open] [data-fx-popper] {
    visibility: visible;
}