.topbar {
  position: fixed;
  inset: 0 0 auto;
  z-index: 20;
  background: #fff;
  padding-left: max(var(--gutter), calc((100% - var(--max)) / 2));
  padding-right: max(var(--gutter), calc((100% - var(--max)) / 2));
  transition: background-color .25s ease, box-shadow .25s ease, color .25s ease;
}

.topbar.over {
  position: fixed;
  background: linear-gradient(#071b13aa, transparent);
}

.topbar.over.scrolled {
  color: #fff;
  background: #062618;
  box-shadow: 0 1px 0 rgb(255 255 255 / 8%);
}

.has-fixed-header { padding-top: 60px; }