.site-header {
  position: sticky;
  top: 0;
  z-index: var(--z-header);
  height: var(--header-height);
  border-bottom: 1px solid var(--border-2);
  background: rgba(17, 17, 17, 0.9);
  backdrop-filter: blur(8px);
}

.site-header__inner {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
}

.site-logo {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-family: var(--font-title);
  font-size: var(--font-size-3);
  letter-spacing: 0;
  text-transform: uppercase;
  white-space: nowrap;
}

.site-logo__mark {
  width: 34px;
  height: 34px;
  border-radius: var(--radius-sm);
  border: 1px solid rgba(255, 214, 10, 0.45);
  background-color: #1b1b1b;
  background-image: url('/logo.jpg');
  background-size: cover;
  background-position: center;
  box-shadow: 0 0 18px rgba(255, 59, 48, 0.35);
}

.site-nav {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.site-nav__link {
  display: inline-flex;
  align-items: center;
  height: 38px;
  padding: 0 var(--space-4);
  border: 1px solid transparent;
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
  transition: all 0.2s ease;
}

.site-nav__link:hover,
.site-nav__link.is-active {
  color: var(--text-primary);
  border-color: var(--border-1);
  background: rgba(255, 59, 48, 0.14);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  min-height: 40px;
  padding: 0 var(--space-4);
  border: 1px solid var(--border-1);
  border-radius: var(--radius-sm);
  font-weight: 600;
  letter-spacing: 0;
  transition:
    transform 0.16s ease,
    box-shadow 0.16s ease,
    background 0.16s ease,
    border-color 0.16s ease;
}

.btn:hover {
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

.btn--primary {
  border-color: #ff8f45;
  color: #fff;
  background: linear-gradient(135deg, var(--brand-primary), var(--brand-secondary));
  box-shadow: var(--glow-primary);
}

.btn--secondary {
  color: var(--text-primary);
  background: linear-gradient(180deg, #2b2b2b, #232323);
  border-color: #595959;
}

.btn--ghost {
  color: var(--text-secondary);
  background: transparent;
  border-color: var(--border-1);
}

.btn--ghost:hover {
  color: var(--text-primary);
  background: rgba(255, 59, 48, 0.1);
  border-color: #7a4b45;
}

.card {
  border: 1px solid var(--border-2);
  border-radius: var(--radius-md);
  background: linear-gradient(180deg, #252525, #1b1b1b);
  box-shadow: var(--shadow-sm);
}

.section {
  padding: var(--space-8) 0;
}

.section__head {
  margin-bottom: var(--space-6);
}

.section__title {
  margin: 0;
  font-family: var(--font-title);
  font-size: clamp(24px, 3vw, 36px);
  line-height: 1.2;
  letter-spacing: 0;
  text-transform: uppercase;
}

.section__desc {
  margin: var(--space-3) 0 0;
  color: var(--text-secondary);
}

.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-2);
  margin-bottom: var(--space-5);
  color: var(--text-muted);
  font-size: var(--font-size-1);
}

.site-footer {
  border-top: 1px solid var(--border-2);
  background: rgba(20, 20, 20, 0.92);
}

.site-footer__inner {
  padding: var(--space-6) 0;
  display: flex;
  justify-content: space-between;
  gap: var(--space-4);
  color: var(--text-secondary);
}

.back-to-top {
  position: fixed;
  right: var(--space-4);
  bottom: var(--space-4);
  z-index: var(--z-overlay);
  opacity: 0;
  pointer-events: none;
  transform: translateY(10px);
  transition: opacity 0.2s ease, transform 0.2s ease;
}

.back-to-top.is-visible {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}

@media (max-width: 991px) {
  .site-nav {
    overflow-x: auto;
    padding-bottom: 2px;
  }
}

@media (max-width: 767px) {
  .site-header {
    height: auto;
    min-height: var(--header-height);
  }

  .site-header__inner {
    padding: var(--space-2) 0 var(--space-1);
    flex-direction: column;
    align-items: flex-start;
    gap: var(--space-2);
  }

  .site-logo {
    font-size: 16px;
  }

  .site-nav {
    width: 100%;
    gap: var(--space-2);
    overflow-x: auto;
    padding-bottom: 4px;
    scrollbar-width: none;
  }

  .site-nav::-webkit-scrollbar {
    display: none;
  }

  .site-nav__link {
    flex: 0 0 auto;
    min-height: 40px;
    padding: 0 14px;
  }

  .site-footer__inner {
    flex-direction: column;
  }
}