html {
  scroll-behavior: smooth;
}

body {
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

::selection {
  background: #e5e7eb;
  color: #111827;
}

::-webkit-scrollbar {
  width: 8px;
}

::-webkit-scrollbar-track {
  background: #f1f5f9;
}

::-webkit-scrollbar-thumb {
  background: #cbd5e1;
  border-radius: 999px;
}

::-webkit-scrollbar-thumb:hover {
  background: #94a3b8;
}

.site-nav {
  background: rgba(255, 255, 255, 0.45);
  backdrop-filter: blur(10px);
  transition: background-color 0.3s ease, box-shadow 0.3s ease;
}

.site-nav.is-scrolled,
.site-nav.menu-open {
  background: rgba(255, 255, 255, 0.88);
  box-shadow: 0 10px 35px rgba(15, 23, 42, 0.08);
}

.mobile-menu {
  max-height: 0;
  opacity: 0;
  overflow: hidden;
  transition: max-height 0.35s ease, opacity 0.25s ease;
}

.mobile-menu.is-open {
  max-height: 28rem;
  opacity: 1;
}

.hero-orb {
  animation: hero-float 20s ease-in-out infinite;
}

.hero-orb-secondary {
  animation-duration: 25s;
  animation-direction: alternate;
}

.section-anchor {
  scroll-margin-top: 7rem;
}

.back-to-top {
  position: fixed;
  right: 1.5rem;
  bottom: 1.5rem;
  z-index: 45;
  display: inline-flex;
  height: 3.25rem;
  width: 3.25rem;
  align-items: center;
  justify-content: center;
  border: 1px solid rgba(229, 231, 235, 0.95);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.92);
  color: #111827;
  box-shadow: 0 18px 35px rgba(15, 23, 42, 0.12);
  backdrop-filter: blur(12px);
  opacity: 0;
  pointer-events: none;
  transform: translate3d(0, 14px, 0);
  transition: opacity 0.25s ease, transform 0.25s ease, border-color 0.25s ease, box-shadow 0.25s ease;
}

.back-to-top:hover {
  border-color: rgba(156, 163, 175, 0.95);
  box-shadow: 0 24px 45px rgba(15, 23, 42, 0.16);
}

.back-to-top.is-visible {
  opacity: 1;
  pointer-events: auto;
  transform: translate3d(0, 0, 0);
}

.article-copy p + p {
  margin-top: 1.75rem;
}

@keyframes hero-float {
  0% {
    transform: translate3d(0, 0, 0) scale(1);
  }

  33% {
    transform: translate3d(60px, -30px, 0) scale(1.1);
  }

  66% {
    transform: translate3d(-45px, 35px, 0) scale(0.96);
  }

  100% {
    transform: translate3d(0, 0, 0) scale(1);
  }
}

@media (max-width: 640px) {
  .back-to-top {
    right: 1rem;
    bottom: 1rem;
  }
}