For example:
.mainpage-columns {
gap: 0.5em; /* unknown property 'gap', but it is actually correct "/
grid-template-columns: [begin] 1fr [end]; /* unexpected token but it is actually valid */
}
.mainpage-columns > div {
padding-inline-start: 1em; /* unknown property but it is actually correct */
padding-inline-end: 1em;
}
Besides, it seems that it cannot recognize CSS variables.