/* Shared top chrome — same file for Rahavirrat (inline pages) and site.css hubs.
   Do not fork these rules per page.
   Mobile (<800px): hamburger. Desktop: horizontal links. */
:root {
  --nav-font: "IBM Plex Sans", sans-serif;
  --nav-text: #f1f5f9;
  --nav-muted: #94a3b8;
  --nav-blue-hot: #60a5fa;
  --nav-edge: #1e293b;
  --nav-blue-dim: rgba(37, 99, 235, 0.14);
}

.topbar {
  position: sticky;
  top: 0;
  z-index: 30;
  border-bottom: 1px solid rgba(30, 41, 59, 0.9);
  background: rgba(2, 6, 23, 0.86);
  backdrop-filter: blur(10px);
}

.topbar-inner {
  max-width: 72rem;
  margin: 0 auto;
  padding: 0.95rem 1.25rem;
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.wordmark {
  font-family: var(--nav-font);
  font-size: 1.2rem;
  font-weight: 700;
  letter-spacing: -0.04em;
  color: #fff;
  margin-right: auto;
  text-decoration: none;
  font-synthesis: none;
}
.wordmark span {
  color: var(--nav-blue-hot);
  font-weight: 500;
}

/* Higher specificity than inline `.site-nav{display:flex}` on hub pages */
.topbar-inner > .nav-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex: 0 0 auto;
  width: 2.5rem;
  height: 2.5rem;
  margin: 0;
  padding: 0;
  border: 1px solid rgba(37, 99, 235, 0.35);
  border-radius: 0.55rem;
  background: var(--nav-blue-dim);
  color: var(--nav-blue-hot);
  cursor: pointer;
}
.topbar-inner > .nav-toggle:hover,
.topbar-inner > .nav-toggle:focus-visible {
  border-color: rgba(96, 165, 250, 0.55);
  outline: none;
}

.nav-toggle-bars,
.nav-toggle-bars::before,
.nav-toggle-bars::after {
  display: block;
  width: 1.05rem;
  height: 2px;
  background: currentColor;
  border-radius: 1px;
  position: relative;
  transition: transform 0.15s ease, opacity 0.15s ease;
}
.nav-toggle-bars::before,
.nav-toggle-bars::after {
  content: "";
  position: absolute;
  left: 0;
}
.nav-toggle-bars::before { top: -6px; }
.nav-toggle-bars::after { top: 6px; }
.nav-toggle[aria-expanded="true"] .nav-toggle-bars {
  background: transparent;
}
.nav-toggle[aria-expanded="true"] .nav-toggle-bars::before {
  top: 0;
  transform: rotate(45deg);
}
.nav-toggle[aria-expanded="true"] .nav-toggle-bars::after {
  top: 0;
  transform: rotate(-45deg);
}

.topbar-inner > .site-nav,
.topbar-inner > nav.site {
  display: none;
  flex-direction: column;
  flex: 1 1 100%;
  justify-content: flex-start;
  gap: 0.15rem;
  width: 100%;
  padding: 0.35rem 0 0.15rem;
  border-top: 1px solid rgba(30, 41, 59, 0.9);
}

.topbar-inner > .site-nav.is-open,
.topbar-inner > nav.site.is-open {
  display: flex;
}

.site-nav a,
nav.site a {
  font-family: var(--nav-font);
  font-size: 0.95rem;
  font-weight: 500;
  font-synthesis: none;
  color: var(--nav-muted);
  padding: 0.7rem 0.35rem;
  border-bottom: 2px solid transparent;
  border-radius: 0.45rem;
  text-decoration: none;
  text-transform: none;
  letter-spacing: normal;
  background: transparent;
  line-height: 1.55;
}

.site-nav a:hover,
nav.site a:hover {
  color: var(--nav-text);
  background: rgba(37, 99, 235, 0.12);
}

.site-nav a.active,
nav.site a.active {
  color: #fff;
  border-bottom-color: transparent;
  background: rgba(37, 99, 235, 0.12);
}

.shelves {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  max-width: 72rem;
  margin: 0 auto;
  padding: 0.85rem 1.25rem 0;
}

.shelves a.shelf {
  appearance: none;
  border: 1px solid transparent;
  background: transparent;
  color: var(--nav-muted);
  font-family: var(--nav-font);
  font-size: 0.95rem;
  font-weight: 600;
  font-synthesis: none;
  padding: 0.55rem 0.95rem;
  border-radius: 0.55rem;
  cursor: pointer;
  text-decoration: none;
  letter-spacing: normal;
  text-transform: none;
}

.shelves a.shelf:hover {
  color: var(--nav-text);
  background: rgba(37, 99, 235, 0.08);
}

.shelves a.shelf.is-active {
  color: #fff;
  background: rgba(37, 99, 235, 0.14);
  border-color: rgba(37, 99, 235, 0.4);
}

@media (min-width: 800px) {
  .topbar-inner {
    flex-wrap: nowrap;
  }
  .topbar-inner > .nav-toggle {
    display: none;
  }
  .topbar-inner > .site-nav,
  .topbar-inner > nav.site {
    display: flex;
    flex-direction: row;
    flex-wrap: wrap;
    flex: 1 1 auto;
    justify-content: flex-end;
    gap: 0.35rem 1rem;
    width: auto;
    padding: 0;
    border-top: 0;
  }
  .site-nav a,
  nav.site a {
    padding: 0.2rem 0;
    border-radius: 0;
  }
  .site-nav a:hover,
  nav.site a:hover {
    background: transparent;
  }
  .site-nav a.active,
  nav.site a.active {
    border-bottom-color: var(--nav-blue-hot);
    background: transparent;
  }
}

@media (max-width: 520px) {
  .topbar-inner { padding: 0.75rem 0.9rem; }
  .shelves { padding: 0.65rem 0.9rem 0; }
}