/* VSS site-wide navigation bar (v-ss.me). Self-contained: its own tokens, follows html[data-theme]. */
.vss-nav {
  --sn-bg: rgba(245, 245, 247, 0.84);
  --sn-border: rgba(0, 0, 0, 0.08);
  --sn-text: #1d1d1f;
  --sn-muted: #6e6e73;
  --sn-accent: #0071e3;
  --sn-accent-soft: rgba(0, 113, 227, 0.1);
  --sn-chip: rgba(0, 0, 0, 0.04);
  --sn-chip-border: rgba(0, 0, 0, 0.1);
  position: sticky;
  top: 0;
  z-index: 1000;
  background: var(--sn-bg);
  border-bottom: 1px solid var(--sn-border);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  backdrop-filter: saturate(180%) blur(20px);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Helvetica Neue", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  line-height: 1.2;
  text-align: left;
}
html[data-theme="dark"] .vss-nav {
  --sn-bg: rgba(22, 22, 24, 0.8);
  --sn-border: rgba(255, 255, 255, 0.09);
  --sn-text: #f5f5f7;
  --sn-muted: #a1a1a6;
  --sn-accent: #0a84ff;
  --sn-accent-soft: rgba(10, 132, 255, 0.16);
  --sn-chip: rgba(255, 255, 255, 0.06);
  --sn-chip-border: rgba(255, 255, 255, 0.12);
}
.vss-nav *, .vss-nav *::before, .vss-nav *::after { box-sizing: border-box; }
.vss-nav-inner {
  max-width: 1140px;
  height: 56px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}
.vss-nav-brand {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-shrink: 0;
  color: var(--sn-text);
  text-decoration: none;
  font-size: 19px;
  font-weight: 700;
  letter-spacing: -0.02em;
}
.vss-nav-badge {
  padding: 2px 7px;
  border-radius: 6px;
  background: var(--sn-accent-soft);
  color: var(--sn-accent);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.02em;
  text-transform: uppercase;
}
.vss-nav-links {
  display: flex;
  align-items: center;
  gap: 22px;
  margin: 0;
  padding: 0;
}
.vss-nav-links a {
  color: var(--sn-muted);
  text-decoration: none;
  font-size: 13.5px;
  font-weight: 500;
  white-space: nowrap;
  transition: color 0.2s ease;
}
.vss-nav-links a:hover { color: var(--sn-text); }
.vss-nav-links a[aria-current="page"] { color: var(--sn-text); font-weight: 600; }
.vss-nav-actions {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}
.vss-nav-lang {
  color: var(--sn-muted);
  text-decoration: none;
  font-size: 12.5px;
  font-weight: 600;
  padding: 5px 9px;
  border-radius: 999px;
  border: 1px solid var(--sn-chip-border);
  background: var(--sn-chip);
}
.vss-nav-lang:hover { color: var(--sn-text); }
.vss-theme-toggle {
  width: 34px;
  height: 34px;
  margin: 0;
  padding: 0;
  border-radius: 50%;
  border: 1px solid var(--sn-chip-border);
  background: var(--sn-chip);
  color: var(--sn-muted);
  font-size: 15px;
  line-height: 1;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: border-color 0.2s ease;
}
.vss-theme-toggle:hover { border-color: var(--sn-accent); }

/* Phones and small tablets: brand + actions on the first row, links scroll sideways on the second */
@media (max-width: 900px) {
  .vss-nav-inner {
    height: auto;
    flex-wrap: wrap;
    padding: 8px 16px 0;
    gap: 0 12px;
  }
  .vss-nav-brand { height: 36px; font-size: 18px; }
  .vss-nav-actions { order: 2; }
  .vss-theme-toggle { width: 32px; height: 32px; font-size: 14px; }
  .vss-nav-links {
    order: 3;
    width: calc(100% + 16px);
    margin-right: -16px;
    gap: 16px;
    padding: 8px 28px 10px 0;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
    /* fade on the right edge: there is more to swipe to */
    -webkit-mask-image: linear-gradient(to right, #000 calc(100% - 36px), transparent);
    mask-image: linear-gradient(to right, #000 calc(100% - 36px), transparent);
  }
  .vss-nav-links::-webkit-scrollbar { display: none; }
  .vss-nav-links a { font-size: 14px; }
}