inset has no effect on non-positioned (static) elements.
Example
.element {/* ⭐️ must be positioned */position:absolute;inset:1em 2em 3em 0; /* top right bottom left */inset:10% 5% -10%; /* top left/right bottom */inset:0 10px; /* top/bottom left/right */inset:20px; /* all edges = 20px */}