/* The shared navigation sits over one persistent interactive scene. */
#site-startup { display: none; }
.is-home-boot #site-startup {
  position: fixed; inset: 0; z-index: 2;
  display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 18px;
  color: #c2cada; background: #04080d;
  font-size: 12px; letter-spacing: .14em; font-variant-numeric: tabular-nums;
}
.startup-track { width: min(180px, 45vw); height: 2px; background: #c2cada26; }
#site-header {
  position: fixed;
  inset: 0 0 auto;
  height: 100px;
  border: 0;
  background: linear-gradient(180deg, #070b12a8, #070b1200);
  backdrop-filter: none;
  -webkit-backdrop-filter: none;
}
body.is-home {
  overflow: hidden;
  min-height: 100svh;
}
body.is-home #site-footer {
  display: flex;
  position: fixed;
  inset: auto 0 0;
  justify-content: center;
  padding: 8px 12px max(8px, env(safe-area-inset-bottom));
  border: 0;
  background: transparent;
  pointer-events: none;
}
body.is-home #site-footer > :not(.site-registration) {
  display: none;
}
body.is-home #site-footer .site-registration {
  pointer-events: auto;
  font-size: 11px;
  color: #c2cada;
  text-shadow: 0 1px 4px #04080d;
}
#site-header .nav a {
  font-size: 16px;
  font-weight: 500;
}
.universe-home {
  position: fixed;
  inset: 0;
  z-index: 0;
  isolation: isolate;
  height: 100svh;
  overflow: hidden;
  background:
    radial-gradient(ellipse at -8% 32%, #254b6770, transparent 55%),
    radial-gradient(ellipse at 93% 80%, #28244d40, transparent 60%), #04080d;
  transition:
    filter 550ms var(--ease),
    transform 550ms var(--ease);
}
.universe-stage {
  position: absolute;
  inset: 0;
  touch-action: pinch-zoom;
  outline-offset: -8px;
  cursor: default;
  opacity: 0;
  transition: opacity 1200ms var(--ease);
}
.universe-home.is-ready .universe-stage {
  opacity: 1;
}
.universe-loader {
  position: absolute;
  inset: 0;
  z-index: 3;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 18px;
  color: #c2cada;
  font-size: 12px;
  letter-spacing: 0.14em;
  pointer-events: none;
  transition: opacity 280ms ease, visibility 280ms ease;
}
.universe-loader svg {
  width: 30px;
  height: 30px;
  stroke-width: 1.2;
  animation: universe-loading-turn 1.6s linear infinite;
}
.universe-load-track {
  width: min(180px, 45vw);
  height: 2px;
  background: #c2cada26;
  overflow: hidden;
}
.universe-load-track span {
  display: block;
  width: 100%;
  height: 100%;
  background: #c2cada;
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 180ms ease;
}
.universe-load-percent {
  font-variant-numeric: tabular-nums;
  font-family: ui-monospace, monospace;
  font-size: 11px;
  letter-spacing: .04em;
}
.universe-continue { margin-inline-start: 16px; color: inherit; }
.universe-home.is-ready .universe-loader,
.universe-home.has-error .universe-loader,
.universe-home.is-covered .universe-loader {
  opacity: 0;
  visibility: hidden;
}
@keyframes universe-loading-turn { to { transform: rotate(360deg); } }
@media (prefers-reduced-motion: reduce) {
  .universe-loader svg { animation: none; }
}
.universe-home.is-returning-out .universe-stage {
  opacity: 0;
  transition-duration: 220ms;
  pointer-events: none;
}
.universe-home.is-returning-in .universe-stage {
  animation: scene-arrival 700ms var(--ease) both;
  pointer-events: none;
}
@keyframes scene-arrival {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}
.universe-home[data-interactive="true"] .universe-stage {
  cursor: grab;
}
.universe-home[data-interactive="true"].is-dragging .universe-stage {
  cursor: grabbing;
}
.universe-canvas {
  display: block;
  width: 100%;
  height: 100%;
}
.chapter-shade {
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: linear-gradient(90deg, #050914d9, #0509148c 30%, #05091400 65%);
  opacity: 0;
  transition: opacity 1100ms var(--ease);
}
.universe-home .chapter-shade {
  opacity: var(--journey-shade, 0);
}
.chapter-copy {
  position: absolute;
  z-index: 2;
  left: var(--page);
  top: 50%;
  width: min(40vw, 600px);
  transform: translateY(calc(-35% + var(--chapter-shift, 0px)));
  pointer-events: none;
  opacity: var(--chapter-visibility, 1);
  transition: opacity 160ms linear;
}
.chapter-label {
  font-size: 12px;
  letter-spacing: 0.22em;
  color: var(--muted);
  margin-bottom: var(--space-4);
}
.chapter-copy h2 {
  font-size: clamp(38px, 4.8vw, 76px);
  line-height: 1.18;
  font-weight: 500;
  letter-spacing: 0.025em;
  text-wrap: balance;
}
.chapter-description {
  color: var(--muted);
  margin-top: var(--space-4);
  font-size: clamp(15px, 1.25vw, 18px);
  line-height: 1.8;
}
.chapter-links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 32px;
  margin-top: var(--space-6);
}
.chapter-links a {
  pointer-events: auto;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 30px;
  min-height: 48px;
  border-bottom: 1px solid var(--line);
  font-size: 15px;
  transition:
    border-color 220ms,
    color 220ms;
}
.chapter-links svg {
  width: 24px;
  height: 24px;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.5;
  transition: transform 300ms var(--ease);
}
.chapter-links a:hover {
  color: #fff;
  border-color: #fff;
}
.chapter-links a:hover svg {
  transform: translateX(5px);
}
.chapter-copy[hidden] {
  display: none;
}
@media (max-aspect-ratio: 17/20) {
  .chapter-copy {
    top: auto;
    bottom: max(42px, env(safe-area-inset-bottom));
    width: calc(100% - 2 * var(--page));
    transform: translateY(var(--chapter-shift, 0px));
  }
  .chapter-copy h2 {
    font-size: clamp(32px, 8vw, 46px);
  }
  .chapter-label {
    margin-bottom: 14px;
  }
  .chapter-description {
    margin-top: 16px;
  }
  .chapter-links {
    margin-top: 24px;
  }
  .chapter-shade {
    background: linear-gradient(0deg, #050914ef, #050914b0 27%, #05091400 65%);
  }
}
@media (max-height: 520px) and (min-aspect-ratio: 17/20) {
  .chapter-copy {
    top: 45%;
  }
  .chapter-label {
    margin-bottom: 8px;
  }
  .chapter-copy h2 {
    font-size: 34px;
  }
  .chapter-description,
  .chapter-links {
    margin-top: 12px;
  }
}
.universe-home::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 1;
  pointer-events: none;
  background: linear-gradient(
    180deg,
    #0002,
    transparent 20%,
    transparent 83%,
    #0003
  );
}
/* Only failures need visible guidance; the ordinary scene has no instruction HUD. */
.universe-feedback {
  position: absolute;
  z-index: 3;
  left: var(--page);
  bottom: max(36px, env(safe-area-inset-bottom));
  max-width: min(540px, calc(100vw - 2 * var(--page)));
}
.universe-status {
  color: #dde2e8;
  font-size: 14px;
  text-shadow: 0 1px 12px #000;
}
.universe-status:empty {
  display: none;
}
.universe-retry {
  min-height: 44px;
  margin-top: 8px;
  padding: 7px 0;
  text-decoration: underline;
  text-underline-offset: 5px;
}
#main {
  position: relative;
  z-index: 2;
  min-height: 100svh;
}
body.is-home #main {
  pointer-events: none;
}
body.content-open #main { padding-top: 100px; }
body.content-open:not(.blog-open) #main { background: #090909e0; }
body.content-open #home-stage {
  filter: blur(20px) brightness(0.65);
  transform: scale(1.035);
  pointer-events: none;
}
body.content-open .universe-feedback {
  opacity: 0;
  visibility: hidden;
}
#site-footer {
  position: relative;
  z-index: 2;
  background: #090909f5;
}
@media (max-width: 900px) {
  #site-header {
    height: 82px;
  }
  body.content-open #main {
    padding-top: 82px;
  }
}
@media (prefers-reduced-motion: reduce) {
  .universe-home,
  .universe-home * {
    animation: none !important;
    transition: none !important;
  }
}