/* ==========================================================================
   Bilingual (EN / 中文) display toggling
   Both languages are rendered by Jekyll; the active one is chosen by the
   data-lang attribute set on <html> before first paint (see _layouts/default.html).
   ========================================================================== */

html[data-lang="zh"] .lang-en { display: none !important; }
html:not([data-lang="zh"]) .lang-zh { display: none !important; }

/* CJK-aware font stack while Chinese is active */
html[data-lang="zh"] body {
  font-family: -apple-system, ".SFNSText-Regular", "San Francisco", "Roboto",
    "Segoe UI", "Helvetica Neue", "Lucida Grande", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", Arial, sans-serif;
}

/* Reserve room on the right of the greedy nav so links never slide under
   the language toggle or the hamburger/more button */
.greedy-nav {
  padding-right: 6.5rem;
}

/* Language toggle button in the masthead.
   right offset keeps it clear of the hamburger/greedy toggle button at every width */
.masthead .lang-toggle {
  position: absolute;
  top: 50%;
  right: 5rem;
  transform: translateY(-50%);
  z-index: 110;
  height: auto;
  padding: 0.2rem 0.7rem;
  border: 1px solid #a7b0b8;
  border-radius: 999px;
  background: transparent;
  color: #4c4c4c;
  font-size: 0.8rem;
  line-height: 1.5;
  font-weight: 600;
  cursor: pointer;
}

.masthead .lang-toggle:hover,
.masthead .lang-toggle:focus {
  border-color: #3a6a8a;
  color: #3a6a8a;
  background: rgba(58, 106, 138, 0.08);
  outline: none;
}

@media print {
  .lang-toggle { display: none !important; }
}