/* ─── Google Fonts ─────────────────────────────────────────────────────────── */
@import url('https://fonts.googleapis.com/css2?family=Outfit:wght@400;500;600;700;800&family=Nunito+Sans:wght@400;600;700&display=swap');

/* ─── Shared Navigation Bar ────────────────────────────────────────────────── */
.site-nav {
  background: #0e1e3d;
  color: #f5f5f5;
  border-bottom: 1px solid rgba(255,255,255,0.08);
  position: sticky;
  top: 0;
  z-index: 1000;
  box-shadow: 0 2px 24px rgba(14,30,61,0.5);
}

.site-nav-inner {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 24px;
  height: 68px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  font-family: 'Nunito Sans', system-ui, sans-serif;
  font-size: 0.92rem;
}

.site-nav-brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: inherit;
  white-space: nowrap;
  flex-shrink: 0;
}

.site-nav-logo-img {
  width: 42px;
  height: 42px;
  border-radius: 10px;
  object-fit: contain;
  filter: brightness(0) invert(1);
  opacity: 0.92;
  flex-shrink: 0;
}

/* Divider between logo and text */
.site-nav-brand::after {
  content: '';
  display: block;
  width: 1px;
  height: 30px;
  background: rgba(255,255,255,0.18);
  flex-shrink: 0;
}

.site-nav-title {
  display: inline-flex;
  flex-direction: column;
  gap: 2px;
  line-height: 1.15;
  font-family: 'Outfit', system-ui, sans-serif;
  font-size: 1rem;
  font-weight: 700;
  color: #fff;
  letter-spacing: -0.01em;
}

.site-nav-subtitle {
  font-family: 'Nunito Sans', system-ui, sans-serif;
  font-size: 0.64rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: rgba(255,255,255,0.42);
  line-height: 1;
}

.site-nav-links {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  flex-wrap: wrap;
}

.site-nav-link {
  text-decoration: none;
  color: rgba(245,245,245,0.78);
  padding: 7px 14px;
  border-radius: 8px;
  border: 1px solid transparent;
  font-weight: 600;
  font-size: 0.85rem;
  transition: background 0.15s ease, color 0.15s ease, border-color 0.15s ease;
}

.site-nav-link:hover,
.site-nav-link:focus-visible {
  background: rgba(255,255,255,0.08);
  border-color: rgba(255,255,255,0.18);
  color: #fff;
  outline: none;
}

.site-nav-topic-jump {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin-left: auto;
}

.topic-jump-label {
  font-size: 0.76rem;
  font-weight: 600;
  letter-spacing: 0.03em;
  color: rgba(255,255,255,0.5);
  white-space: nowrap;
}

.topic-jump-select {
  padding: 7px 14px 7px 12px;
  border-radius: 8px;
  border: 1px solid rgba(255,255,255,0.22);
  background: rgba(255,255,255,0.06);
  color: #ffffff;
  font-size: 0.84rem;
  font-family: 'Nunito Sans', system-ui, sans-serif;
  font-weight: 600;
  outline: none;
  min-width: 13rem;
  cursor: pointer;
  transition: border-color 0.15s, background 0.15s;
}

.topic-jump-select:hover,
.topic-jump-select:focus {
  border-color: rgba(255,255,255,0.4);
  background: rgba(255,255,255,0.1);
}

.topic-jump-select option {
  color: #111827;
  background: #ffffff;
}

/* ─── Responsive ───────────────────────────────────────────────────────────── */
@media (max-width: 860px) {
  .site-nav-inner {
    flex-wrap: wrap;
    height: auto;
    padding: 10px 16px;
  }
  .site-nav-topic-jump {
    width: 100%;
    padding-bottom: 4px;
  }
}

@media (max-width: 580px) {
  .site-nav-inner {
    flex-direction: column;
    align-items: stretch;
    gap: 8px;
  }
  .site-nav-brand::after { display: none; }
  .topic-jump-select { width: 100%; }
}

/* ─── Worksheets login button ──────────────────────────────────────────────── */
.site-nav-login {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 8px 18px;
  border-radius: 8px;
  border: 1.5px solid rgba(240,165,0,0.55);
  background: rgba(240,165,0,0.12);
  color: #f0a500;
  font-family: 'Nunito Sans', system-ui, sans-serif;
  font-size: 0.84rem;
  font-weight: 700;
  text-decoration: none;
  letter-spacing: 0.01em;
  white-space: nowrap;
  flex-shrink: 0;
  transition: background 0.15s ease, border-color 0.15s ease, color 0.15s ease, transform 0.1s ease;
}

.site-nav-login:hover {
  background: rgba(240,165,0,0.22);
  border-color: #f0a500;
  color: #fbbf24;
  transform: translateY(-1px);
  text-decoration: none;
}

.site-nav-login svg {
  width: 15px;
  height: 15px;
  flex-shrink: 0;
}

@media (max-width: 580px) {
  .site-nav-login span { display: none; }
  .site-nav-login { padding: 8px 10px; }
}