.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.topbar {
  height: 72px;
  position: sticky;
  top: 0;
  z-index: 30;
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr);
  align-items: center;
  gap: 24px;
  padding: 0 24px;
  background: rgba(16, 18, 15, .96);
  color: #fff;
  border-bottom: 1px solid #282b26;
  backdrop-filter: blur(14px);
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  color: inherit;
  text-decoration: none;
  white-space: nowrap;
}
.brand-mark {
  display: grid;
  place-items: center;
  width: 42px;
  height: 42px;
  background: var(--acid);
  color: var(--ink);
  font: 600 12px var(--mono);
}
.brand strong { display: block; letter-spacing: .08em; font-size: 14px; }
.brand small { display: block; margin-top: 3px; color: #9ca298; font-size: 11px; }

.site-nav {
  grid-column: 2;
  justify-self: center;
  display: flex;
  gap: 8px;
}
.site-nav a,
.header-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 38px;
  padding: 0 14px;
  border: 1px solid #41453d;
  border-radius: 2px;
  background: transparent;
  color: #fff;
  font: inherit;
  text-decoration: none;
  white-space: nowrap;
  cursor: pointer;
}
.site-nav a:hover,
.header-button:hover { border-color: var(--acid); }
.site-nav a[aria-current="page"],
.header-button--primary {
  background: var(--acid);
  border-color: var(--acid);
  color: var(--ink);
  font-weight: 700;
}
.header-tools { grid-column: 3; justify-self: end; }

@media (max-width: 900px) {
  .topbar {
    height: 100px;
    grid-template-columns: minmax(0, 1fr) auto;
    grid-template-rows: 42px 36px;
    column-gap: 12px;
    row-gap: 6px;
    padding: 8px 14px;
  }
  .brand { grid-column: 1; grid-row: 1; }
  .header-tools { grid-column: 2; grid-row: 1; }
  .site-nav { grid-column: 1 / -1; grid-row: 2; min-width: 0; width: 100%; overflow-x: auto; scrollbar-width: none; }
  .site-nav a { min-height: 34px; }
}
@media (max-width: 480px) {
  .brand strong { font-size: 12px; }
  .brand small { display: none; }
  .header-button { min-height: 34px; padding: 0 9px; font-size: 11px; }
  .site-nav { gap: 5px; }
  .site-nav a { padding: 0 9px; font-size: 11px; }
}