/* Navigation */
.sb-nav {
  position: sticky;
  top: 0;
  z-index: 60;
  background: rgba(246, 241, 231, 0.78);
  backdrop-filter: saturate(140%) blur(14px);
  -webkit-backdrop-filter: saturate(140%) blur(14px);
  border-bottom: 1px solid var(--line);
}
.sb-nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  height: 68px;
}
.sb-mark {
  display: inline-flex;
  align-items: center;
  color: var(--ink);
  line-height: 0;
}
.sb-mark-img {
  display: block;
  height: 36px;
  width: auto;
  /* Source is white on transparent — invert it so it reads on the ivory nav */
  filter: invert(1);
}
@media (max-width: 520px) {
  .sb-mark-img { height: 30px; }
}

.sb-nav-links {
  display: flex; align-items: center; gap: 30px;
  font-size: 14px;
}
.sb-nav-links a {
  color: var(--ink-2);
  position: relative;
  padding: 6px 0;
  letter-spacing: -0.005em;
}
.sb-nav-links a::after {
  content: "";
  position: absolute;
  left: 0; right: 100%; bottom: 0;
  height: 1px;
  background: var(--clay);
  transition: right 250ms ease;
}
.sb-nav-links a:hover::after { right: 0; }

.sb-nav-right { display: flex; align-items: center; gap: 16px; }
.sb-lang {
  display: flex; gap: 2px;
  font-size: 11px;
  color: var(--ink-mute);
  letter-spacing: 0.06em;
  border: 1px solid var(--line);
  border-radius: var(--r-pill);
  padding: 4px 4px;
}
.sb-lang span {
  padding: 3px 8px;
  border-radius: var(--r-pill);
  cursor: pointer;
  font-family: var(--mono);
}
.sb-lang .on { background: var(--ink); color: var(--paper); }

@media (max-width: 880px) {
  .sb-nav-links { display: none; }
  .sb-nav-right .sb-lang { display: none; }
}