/* 筑码引擎 · 官网统一顶栏 */
:root {
  --blue: #2563eb;
  --blue-dark: #1d4ed8;
  --text: #0f172a;
  --muted: #64748b;
  --card: #fff;
  --border: #e2e8f0;
}
.zm-nav {
  background: var(--card);
  border-bottom: 1px solid var(--border);
  position: sticky; top: 0; z-index: 100;
}
.zm-nav-inner {
  max-width: 1120px; margin: 0 auto; padding: 0 24px;
  height: 64px; display: flex; align-items: center; gap: 24px;
}
.zm-logo { display: flex; align-items: center; flex-shrink: 0; text-decoration: none; line-height: 0; }
.zm-logo img { height: 36px; width: auto; display: block; }
.zm-nav-links {
  display: flex; gap: 24px; font-size: 15px; align-items: center; flex-wrap: wrap;
  flex: 1; justify-content: center;
}
.zm-nav-links a { color: inherit; text-decoration: none; }
.zm-nav-links a.active { color: var(--blue); font-weight: 600; border-bottom: 2px solid var(--blue); padding-bottom: 4px; }
.zm-nav-right {
  display: flex; align-items: center; gap: 10px; flex-shrink: 0; margin-left: auto;
}
.zm-nav-cta {
  background: var(--blue); color: #fff; padding: 10px 18px; border-radius: 8px;
  font-size: 14px; font-weight: 600; text-decoration: none; white-space: nowrap;
}
.zm-nav-cta-muted {
  background: #fff; color: var(--blue); border: 1px solid #bfdbfe;
}
.zm-nav-auth-btn {
  background: var(--blue); color: #fff; padding: 10px 22px; border-radius: 8px;
  font-size: 14px; font-weight: 700; text-decoration: none; white-space: nowrap;
  box-shadow: 0 2px 8px rgba(37, 99, 235, 0.25);
}
.zm-nav-auth-btn:hover { background: var(--blue-dark); color: #fff; }
.zm-nav-auth-btn.is-logout {
  background: #fff; color: #dc2626; border: 1px solid #fecaca;
  box-shadow: none;
}
.zm-nav-auth-btn.is-logout:hover { background: #fef2f2; color: #b91c1c; }
@media (max-width: 900px) {
  .zm-nav-links { display: none; }
  .zm-nav-inner { gap: 12px; }
  .zm-nav-cta { display: none; }
}