Some styles are lost after optimizeCss()

[rkakrik]

I am using sveltekit with carbon. In dev mode everything is working, but after build with optimizeCss() some styles are lost (h2, SideNavMenu, etc). Without optimizeCss():

    font-size: 2rem;
    font-weight: 400;
    line-height: 1.25;
    letter-spacing: 0;