/* ═══════════════════════════════════════════════════════════════
   Perihelion X — Solar System Navigation
   ═══════════════════════════════════════════════════════════════ */

html, body {
  width: 100%;
  height: 100%;
  overflow: hidden;
  background-color: var(--bg);
  color: var(--white);
  font-family: var(--font);
  -webkit-font-smoothing: antialiased;
}

/* ── Canvas / vignette (same as entry) ──────────────────────── */
#starfield {
  position: fixed;
  inset: 0;
  width: 100%;
  height: 100%;
  z-index: 0;
  display: block;
  pointer-events: none;
}

.vignette {
  position: fixed;
  inset: 0;
  z-index: 1;
  pointer-events: none;
  background: radial-gradient(
    ellipse at center,
    transparent 40%,
    rgba(4, 4, 10, 0.5) 70%,
    rgba(2, 2, 8, 0.85) 100%
  );
}

/* ── Overlays ────────────────────────────────────────────────── */
.flash-overlay,
.transition-overlay {
  position: fixed;
  inset: 0;
  z-index: 200;
  pointer-events: none;
  opacity: 0;
}

.flash-overlay     { background: #ffffff; }
.transition-overlay { background: #080810; }

/* ── Mute toggle ─────────────────────────────────────────────── */
.mute-toggle {
  position: fixed;
  top: 1.5rem;
  left: 50%;
  transform: translateX(-50%);
  right: auto;
  z-index: 100;
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: transparent;
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: 50%;
  cursor: pointer;
  color: rgba(255, 255, 255, 0.6);
  transition: color 0.25s ease, border-color 0.25s ease, background-color 0.25s ease;
}

.mute-toggle:hover {
  color: #fff;
  border-color: rgba(255, 255, 255, 0.6);
  background-color: rgba(255, 255, 255, 0.05);
}

.mute-toggle:focus-visible {
  outline: 2px solid #fff;
  outline-offset: 4px;
}

.mute-icon {
  width: 18px;
  height: 18px;
  position: absolute;
  transition: opacity 0.2s ease;
}

.mute-icon.mute-off { opacity: 0; }
.mute-toggle[aria-pressed="true"] .mute-icon.mute-on  { opacity: 0; }
.mute-toggle[aria-pressed="true"] .mute-icon.mute-off { opacity: 1; }

/* ── Header ──────────────────────────────────────────────────── */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 50;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.5rem 2rem;
  opacity: 0;
  /* Subtle gradient so it doesn't fight the stars */
  background: linear-gradient(to bottom, rgba(8, 8, 16, 0.7) 0%, transparent 100%);
  pointer-events: none;
}

.site-header.visible {
  pointer-events: auto;
}

.site-wordmark {
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.25em;
  text-decoration: none;
  color: rgba(255, 255, 255, 0.5);
  text-transform: uppercase;
  transition: color 0.25s ease;
}

.site-wordmark:hover {
  color: #fff;
}

.site-header-right {
  display: flex;
  align-items: center;
  gap: 1.5rem;
}

.site-header-label {
  font-size: 0.7rem;
  font-weight: 300;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: rgba(255, 255, 255, 0.3);
}

.site-header-credits {
  font-size: 0.65rem;
  font-weight: 300;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: rgba(255, 255, 255, 0.2);
  text-decoration: none;
  transition: color 0.25s ease;
}

.site-header-credits:hover {
  color: rgba(255, 255, 255, 0.6);
}

/* ── Scroll hint ─────────────────────────────────────────────── */
.scroll-hint {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  z-index: 50;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.65rem;
  font-weight: 300;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: rgba(255, 255, 255, 0.3);
  opacity: 0;
  transition: opacity 0.4s ease;
}

.scroll-hint svg {
  width: 16px;
  height: 16px;
  animation: scrollArrow 1.6s ease-in-out infinite;
}

@keyframes scrollArrow {
  0%, 100% { transform: translateX(0); opacity: 0.3; }
  50%       { transform: translateX(4px); opacity: 0.8; }
}

/* ── Solar track layout ──────────────────────────────────────── */
.solar-track-wrapper {
  position: relative;
  z-index: 10;
  width: 100%;
  height: 100vh;
  display: flex;
  align-items: center;
  overflow-x: auto;
  overflow-y: hidden;
  scrollbar-width: none;           /* Firefox */
  -ms-overflow-style: none;        /* IE */
  cursor: grab;
}

.solar-track-wrapper:active {
  cursor: grabbing;
}

.solar-track-wrapper::-webkit-scrollbar {
  display: none;                   /* Chrome/Safari */
}

.solar-track {
  display: flex;
  align-items: center;
  flex-shrink: 0;
  padding: 0 15vw 0 10vw;
  gap: 0;                          /* gaps controlled per-item */
}

/* ── Body items ──────────────────────────────────────────────── */
.body-item {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  cursor: pointer;
  outline: none;
  /* horizontal spacing between bodies */
  margin-right: 8vw;
}

.body-item:last-child {
  margin-right: 0;
}

/* Larger gap after the Sun */
.sun-item {
  margin-right: 12vw;
}

/* ── Orbit ring ──────────────────────────────────────────────── */
.orbit-ring {
  position: absolute;
  inset: -30%;
  border-radius: 50%;
  border: 1px solid rgba(255, 255, 255, 0.06);
  transform: scale(0.9);
  transition: transform 0.5s ease, border-color 0.5s ease, opacity 0.5s ease;
  opacity: 0;
  animation: orbitSpin 20s linear infinite;
  pointer-events: none;
}

.body-item:hover .orbit-ring,
.body-item:focus-visible .orbit-ring {
  opacity: 1;
  transform: scale(1);
  border-color: rgba(255, 255, 255, 0.15);
}

@keyframes orbitSpin {
  from { transform: rotate(0deg) scale(0.9); }
  to   { transform: rotate(360deg) scale(0.9); }
}

.body-item:hover .orbit-ring,
.body-item:focus-visible .orbit-ring {
  animation: orbitSpinHover 20s linear infinite;
}

@keyframes orbitSpinHover {
  from { transform: rotate(0deg) scale(1); }
  to   { transform: rotate(360deg) scale(1); }
}

/* ── Orb base ────────────────────────────────────────────────── */
.orb {
  position: relative;
  border-radius: 50%;
  transition: transform 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.body-item:hover .orb,
.body-item:focus-visible .orb {
  transform: scale(1.1);
}

.orb-core {
  position: absolute;
  inset: 0;
  border-radius: 50%;
  overflow: hidden;
}

.orb-glow {
  position: absolute;
  inset: -40%;
  border-radius: 50%;
  opacity: 0;
  transition: opacity 0.4s ease;
  pointer-events: none;
}

.body-item:hover .orb-glow,
.body-item:focus-visible .orb-glow {
  opacity: 1;
}

/* ── Per-planet orb sizes and colours ───────────────────────── */

/* ── A6 / A5: Surface & corona keyframes ─────────────────────── */

/* Sun corona pulses — grid centres the elements so only scale needed */
@keyframes sunCorona1 {
  0%, 100% { transform: scale(1);    opacity: 0.55; }
  50%       { transform: scale(1.12); opacity: 0.25; }
}
@keyframes sunCorona2 {
  0%, 100% { transform: scale(1.08); opacity: 0.30; }
  50%       { transform: scale(0.96); opacity: 0.55; }
}
@keyframes sunCorona3 {
  0%, 100% { transform: scale(1);    opacity: 0.18; }
  60%       { transform: scale(1.22); opacity: 0.06; }
}
@keyframes sunRotate {
  from { transform: rotate(0deg); }
  to   { transform: rotate(360deg); }
}


/* Earth cloud shimmer */
@keyframes earthCloud {
  0%   { background-position: 0% 50%; }
  100% { background-position: 100% 50%; }
}

/* Mars dust swirl */
@keyframes marsDust {
  from { transform: rotate(0deg);   opacity: 0.18; }
  to   { transform: rotate(360deg); opacity: 0.22; }
}

/* Ice giant hue shift */
@keyframes iceShift {
  0%, 100% { filter: hue-rotate(0deg); }
  50%       { filter: hue-rotate(18deg); }
}

/* ── A5: Sun corona — always-visible, independent of hover ───── */

/* Sun — largest */
.sun-orb {
  width: 120px;
  height: 120px;
  overflow: visible;
}
.sun-orb .orb-core {
  background: radial-gradient(circle at 38% 38%, #ffe57a, #FDB813 50%, #d4860a);
  animation: sunRotate 40s linear infinite;
}

/* Sun corona — always visible, independent of hover state.
   .sun-corona-wrap sits inside .sun-orb (.orb) but has NO border-radius
   and overflow:visible, so its children escape the orb boundary freely.
   The orb has border-radius:50% which Safari uses to clip direct children
   — the wrap is the escape hatch: no border-radius = no clipping.
   Children are sized as % of the wrap (= % of orb) and centred with
   translate(-50%,-50%) which is reliable since we're not chaining through
   multiple percentage-sized ancestors. */
.sun-orb .orb-glow {
  display: none !important;
}

.sun-item .orb {
  overflow: visible;
}

/* Corona wrap: grid centres all three layers on the orb centre without
   relying on top/left percentages (which resolve to 0 in Safari before
   GSAP has sized the orb, causing the corona to appear at the wrong
   position on first paint). Grid place-items:center works purely from
   the grid algorithm, independent of the element's computed pixel size. */
.sun-corona-wrap {
  position: absolute;
  inset: 0;
  border-radius: 0;
  overflow: visible;
  pointer-events: none;
  z-index: 3;
  display: grid;
  place-items: center;
}

.sun-corona-inner,
.sun-corona-mid,
.sun-corona-outer {
  /* All three layers occupy the single grid cell and stack via grid-area */
  grid-area: 1 / 1;
  border-radius: 50%;
  pointer-events: none;
  will-change: transform, opacity;
}

/* Inner: 220% of orb */
.sun-corona-inner {
  width: 220%;
  height: 220%;
  background: radial-gradient(circle, rgba(253,184,19,0.55) 0%, rgba(253,150,0,0.28) 38%, transparent 62%);
  animation: sunCorona1 3.8s ease-in-out infinite;
}

/* Mid: 360% of orb */
.sun-corona-mid {
  width: 360%;
  height: 360%;
  background: radial-gradient(circle, rgba(255,220,80,0.22) 0%, rgba(253,184,19,0.10) 40%, transparent 62%);
  animation: sunCorona2 5.2s ease-in-out infinite;
}

/* Outer: 560% of orb */
.sun-corona-outer {
  width: 560%;
  height: 560%;
  background: radial-gradient(circle, rgba(253,184,19,0.12) 0%, rgba(253,130,0,0.06) 35%, transparent 58%);
  animation: sunCorona3 7.5s ease-in-out infinite;
}

/* ── G3: Realistic planet textures ───────────────────────────── */

/* Mercury — cratered grey rock: high-contrast craters suggested by radial layers */
.mercury-orb {
  width: 30px;
  height: 30px;
}
.mercury-orb .orb-core {
  background:
    radial-gradient(circle at 62% 28%, rgba(255,255,255,0.06) 0%, transparent 18%),
    radial-gradient(circle at 25% 65%, rgba(0,0,0,0.18) 0%, transparent 20%),
    radial-gradient(circle at 75% 70%, rgba(0,0,0,0.12) 0%, transparent 14%),
    radial-gradient(circle at 40% 40%, rgba(180,180,180,0.08) 0%, transparent 30%),
    radial-gradient(circle at 38% 35%, #d2d0cc, #9B9B9B 48%, #6a6560);
}
.mercury-orb .orb-glow {
  background: radial-gradient(circle, rgba(155,155,155,0.25) 0%, transparent 70%);
}

/* Venus — thick sulphuric acid cloud layers: ochre with swirling opacity bands */
@keyframes venusAtmos {
  0%   { background-position: 0% 0%;   }
  100% { background-position: 200% 0%; }
}
.venus-orb {
  width: 52px;
  height: 52px;
}
.venus-orb .orb-core {
  background:
    radial-gradient(circle at 38% 35%, #f5dfa0, #d4a055 52%, #9a6020);
}
.venus-orb .orb-glow {
  background: radial-gradient(circle, rgba(232,196,106,0.32) 0%, transparent 70%);
}
.venus-orb .orb-core::after {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: 50%;
  background:
    repeating-linear-gradient(
      108deg,
      rgba(255,248,210,0)    0%,
      rgba(255,248,210,0.08) 12%,
      rgba(180,130,60,0.06)  22%,
      rgba(255,248,210,0.04) 35%,
      rgba(255,248,210,0)    50%
    );
  background-size: 300% 100%;
  animation: venusAtmos 24s linear infinite;
}

/* Earth — blue ocean dominant with green-brown continental hint + cloud shimmer */
@keyframes earthLand {
  0%   { background-position: 0% 50%;   }
  100% { background-position: 200% 50%; }
}
.earth-orb {
  width: 54px;
  height: 54px;
}
.earth-orb .orb-core {
  background:
    radial-gradient(circle at 58% 55%, rgba(34,120,40,0.28) 0%, transparent 30%),
    radial-gradient(circle at 30% 40%, rgba(50,140,60,0.22) 0%, transparent 22%),
    radial-gradient(circle at 38% 35%, #94d4f0, #4B9CD3 48%, #1a5a8a);
}
.earth-orb .orb-glow {
  background: radial-gradient(circle, rgba(75,156,211,0.38) 0%, transparent 70%);
}
.earth-orb .orb-core::after {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: 50%;
  background:
    repeating-linear-gradient(
      98deg,
      rgba(255,255,255,0)    0%,
      rgba(255,255,255,0.09) 15%,
      rgba(255,255,255,0.05) 28%,
      rgba(255,255,255,0)    40%
    );
  background-size: 280% 100%;
  animation: earthLand 14s linear infinite;
}

/* Mars — rusted terracotta with a faint polar ice cap suggestion at top */
.mars-orb {
  width: 40px;
  height: 40px;
  overflow: visible;
}
.mars-orb .orb-core {
  background:
    radial-gradient(circle at 50% 8%, rgba(240,240,230,0.28) 0%, transparent 22%),
    radial-gradient(circle at 62% 62%, rgba(100,30,0,0.25) 0%, transparent 28%),
    radial-gradient(circle at 30% 50%, rgba(200,80,30,0.15) 0%, transparent 30%),
    radial-gradient(circle at 38% 35%, #ea7248, #C1440E 52%, #7a2000);
}
.mars-orb .orb-glow {
  background: radial-gradient(circle, rgba(193,68,14,0.32) 0%, transparent 70%);
}
.mars-orb .orb-core::after {
  content: '';
  position: absolute;
  inset: -10%;
  border-radius: 50%;
  background: conic-gradient(
    from 0deg,
    rgba(220,100,40,0)    0%,
    rgba(220,100,40,0.10) 25%,
    rgba(220,100,40,0)    50%,
    rgba(200,80,20,0.07)  75%,
    rgba(220,100,40,0)    100%
  );
  animation: marsDust 22s linear infinite;
}

/* Jupiter — detailed horizontal band system with Great Red Spot hint */
@keyframes jupiterBands {
  from { background-position: 0 0, 0 0, 0 0; }
  to   { background-position: 120px 0, 0 0, 0 0; }
}
.jupiter-orb {
  width: 95px;
  height: 95px;
}
.jupiter-orb .orb-core {
  background-image:
    repeating-linear-gradient(
      180deg,
      rgba(255,230,180,0.08)  0px,
      rgba(255,230,180,0.08)  4px,
      rgba(140,70,10,0.09)    4px,
      rgba(140,70,10,0.09)    9px,
      rgba(220,170,80,0.06)   9px,
      rgba(220,170,80,0.06)   14px,
      transparent             14px,
      transparent             20px
    ),
    radial-gradient(ellipse at 68% 60%, rgba(160,60,40,0.30) 0%, rgba(160,60,40,0.08) 14%, transparent 20%),
    radial-gradient(circle at 38% 35%, #f0d090, #C88B3A 50%, #7a4a10);
  background-size: 100% 100%, 100% 100%, 100% 100%;
  animation: jupiterBands 14s linear infinite;
}
.jupiter-orb .orb-glow {
  background: radial-gradient(circle, rgba(200,139,58,0.28) 0%, transparent 70%);
}

/* Saturn — warm gold with subtle equatorial band hints */
@keyframes saturnBands {
  from { background-position: 0 0, 0 0; }
  to   { background-position: 80px 0, 0 0; }
}
.saturn-orb {
  width: 78px;
  height: 78px;
}
.saturn-orb .orb-core {
  background-image:
    repeating-linear-gradient(
      180deg,
      rgba(220,200,120,0.06) 0px,
      rgba(220,200,120,0.06) 5px,
      rgba(150,120,50,0.06)  5px,
      rgba(150,120,50,0.06)  11px,
      transparent            11px,
      transparent            18px
    ),
    radial-gradient(circle at 38% 35%, #f8eebc, #E4D191 50%, #a89040);
  background-size: 100% 100%, 100% 100%;
  animation: saturnBands 20s linear infinite;
}
.saturn-orb .orb-glow {
  background: radial-gradient(circle, rgba(228,209,145,0.28) 0%, transparent 70%);
}

/* Saturn ring SVG — face-on concentric rings surrounding the orb.
   200% × 200% of the orb, offset -50% each side to stay centred.
   No tilt: rings are circular, same plane as Titan's orbit. */
.saturn-rings {
  position: absolute;
  width: 200%;
  height: 200%;
  left: -50%;
  top: -50%;
  pointer-events: none;
  z-index: 2;
}

/* Uranus — pale blue-green featureless disc with faint limb darkening */
.uranus-orb {
  width: 64px;
  height: 64px;
}
.uranus-orb .orb-core {
  background:
    radial-gradient(circle at 50% 50%, transparent 55%, rgba(20,80,80,0.25) 100%),
    radial-gradient(circle at 38% 35%, #c8f5f5, #7DE8E8 50%, #388888);
  animation: iceShift 9s ease-in-out infinite;
}
.uranus-orb .orb-glow {
  background: radial-gradient(circle, rgba(125,232,232,0.28) 0%, transparent 70%);
}

/* Neptune — deep cobalt blue with faint storm-band suggestion */
@keyframes neptuneStorm {
  0%   { background-position: 0% 50%;   }
  100% { background-position: 300% 50%; }
}
.neptune-orb {
  width: 60px;
  height: 60px;
}
.neptune-orb .orb-core {
  background:
    radial-gradient(circle at 50% 50%, transparent 58%, rgba(10,15,60,0.30) 100%),
    radial-gradient(circle at 38% 35%, #7a98e8, #3F54BA 50%, #0e1e60);
  animation: iceShift 11s ease-in-out infinite reverse;
}
.neptune-orb .orb-core::after {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: 50%;
  background: repeating-linear-gradient(
    170deg,
    rgba(120,160,255,0)    0%,
    rgba(120,160,255,0.06) 18%,
    rgba(30,60,160,0.05)   30%,
    rgba(120,160,255,0)    45%
  );
  background-size: 400% 100%;
  animation: neptuneStorm 30s linear infinite;
}
.neptune-orb .orb-glow {
  background: radial-gradient(circle, rgba(63,84,186,0.32) 0%, transparent 70%);
}

/* Pluto — small, icy, pale terracotta dwarf planet */
.pluto-orb {
  width: 14px;
  height: 14px;
}
.pluto-orb .orb-core {
  background:
    radial-gradient(circle at 38% 35%, #d4b99a, #A07850 52%, #5a3e28);
}
.pluto-orb .orb-glow {
  background: radial-gradient(circle, rgba(160, 120, 80, 0.3) 0%, transparent 70%);
}

/* Pluto item — extra space before Kuiper Belt */
.pluto-item {
  margin-right: 8vw;
}

/* ── Planet label ────────────────────────────────────────────── */
.body-label {
  position: absolute;
  top: calc(100% + 1.5rem);
  left: 50%;
  transform: translateX(-50%) translateY(6px);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.35rem;
  text-align: center;
  white-space: nowrap;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s ease, transform 0.3s ease;
}

.body-item:hover .body-label,
.body-item:focus-visible .body-label {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

.body-name {
  display: block;
  font-size: 0.85rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: #fff;
}

.body-desc {
  display: block;
  font-size: 0.7rem;
  font-weight: 300;
  letter-spacing: 0.04em;
  color: rgba(255, 255, 255, 0.45);
  max-width: 220px;
  white-space: normal;
  text-align: center;
  line-height: 1.5;
}

/* Sun item — label above the orb to avoid overflow */
.sun-item .body-label {
  top: auto;
  bottom: calc(100% + 1.5rem);
  transform: translateX(-50%) translateY(-6px);
}

.sun-item:hover .body-label,
.sun-item:focus-visible .body-label {
  transform: translateX(-50%) translateY(0);
}

/* ── Saturn item — extra vertical space for rings ────────────── */
.saturn-item .orb {
  overflow: visible;
}

/* ── Page entry animation state (set by JS) ──────────────────── */
.body-item {
  opacity: 0;
  transform: translateY(24px);
}

/* ── Mobile — vertical scroll ────────────────────────────────── */
@media (max-width: 768px) {
  /* Let the page itself scroll — body/html overflow:hidden blocks native scroll */
  html, body {
    height: auto;
    overflow: visible;
  }

  .solar-track-wrapper {
    height: auto;
    min-height: 100vh;
    min-height: 100svh;
    overflow-x: hidden;
    overflow-y: visible;
    align-items: flex-start;
    padding-top: 7rem;
    padding-bottom: 5rem;
  }

  .solar-track {
    flex-direction: column;
    align-items: center;
    padding: 0 1.5rem;
    gap: 9rem;
    width: 100%;
  }

  .body-item {
    margin-right: 0 !important;
    padding-bottom: 4.5rem; /* room for label */
  }

  .scroll-hint {
    display: none;
  }

  .site-header {
    padding: 1.25rem 1.5rem;
  }

  /* Labels always visible on mobile — below the orb, tight gap */
  .body-label {
    opacity: 1;
    top: calc(100% + 0.2rem);
    bottom: auto;
    transform: translateX(-50%) translateY(0);
  }

  /* Sun label also below on mobile — consistent with all others */
  .sun-item .body-label {
    opacity: 1;
    top: calc(100% + 0.2rem);
    bottom: auto;
    transform: translateX(-50%) translateY(0);
  }

  /* Only show the planet name on mobile — descriptions clutter the column */
  .body-desc,
  .live-arc-wrap,
  .live-distance {
    display: none;
  }

  /* Padding below each item to give the label room */
  .body-item {
    padding-top: 0;
    padding-bottom: 2rem;
  }

  /* Extra scroll clearance at the bottom of the page */
  .solar-track-wrapper {
    padding-bottom: 8rem;
  }

  /* Hide decorative landmarks that create huge vertical gaps in the column layout */
  .frost-line,
  .asteroid-belt,
  .kuiper-belt,
  .heliopause,
  .oort-cloud,
  .voyager-dot,
  .pluto-item {
    display: none !important;
  }

  /* Moon orbits are large fixed-pixel circles that overflow the column layout */
  .moon-system {
    display: none !important;
  }


  /* Orbit rings extend 30% beyond the orb — clip them so they don't create
     invisible touch zones or horizontal overflow in the column */
  .orbit-ring {
    display: none;
  }

  /* Prevent any orb overflow spilling horizontally */
  .body-item {
    overflow: hidden;
  }

  /* Scale toggle hidden on mobile — aesthetic mode is fixed */
  .scale-toggle,
  .scale-annotation,
  .mass-callout {
    display: none !important;
  }

  /* APOD widget has no room on mobile — hide it */
  .apod-widget {
    display: none !important;
  }

  /* Planet hover preview card is desktop-only (no hover on touch) */
  .planet-preview-card {
    display: none !important;
  }

  /* Keyboard nav hint is irrelevant on touch */
  .keyboard-hint {
    display: none !important;
  }
}

/* ── Mobile tap hint ─────────────────────────────────────────── */
.mobile-tap-hint {
  display: none; /* hidden on desktop */
}

@media (max-width: 768px) {
  .mobile-tap-hint {
    display: block;
    position: fixed;
    bottom: 2.5rem;
    left: 50%;
    transform: translateX(-50%);
    z-index: 50;
    font-size: 0.62rem;
    font-weight: 300;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: rgba(255, 255, 255, 0.55);
    white-space: nowrap;
    pointer-events: none;
    opacity: 1;
    transition: opacity 0.6s ease;
  }

  .mobile-tap-hint.hidden {
    opacity: 0;
  }
}

/* ── B1: Scale mode toggle button ────────────────────────────── */
.scale-toggle {
  position: fixed;
  bottom: 2rem;
  left: 2rem;
  z-index: 50;
  display: flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.55rem 1rem;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.14);
  border-radius: 2rem;
  cursor: pointer;
  color: rgba(255, 255, 255, 0.5);
  font-family: var(--font);
  font-size: 0.65rem;
  font-weight: 400;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  transition: color 0.25s ease, border-color 0.25s ease, background 0.25s ease;
  opacity: 0;
}

.scale-toggle:hover {
  color: #fff;
  border-color: rgba(255, 255, 255, 0.4);
  background: rgba(255, 255, 255, 0.07);
}

.scale-toggle:focus-visible {
  outline: 2px solid rgba(255, 255, 255, 0.6);
  outline-offset: 4px;
}

.scale-toggle svg {
  width: 14px;
  height: 14px;
  flex-shrink: 0;
  transition: transform 0.3s ease;
}

.scale-toggle.active {
  color: rgba(253, 184, 19, 0.9);
  border-color: rgba(253, 184, 19, 0.35);
  background: rgba(253, 184, 19, 0.06);
}

/* B1: True scale annotation banner */
.scale-annotation {
  position: fixed;
  bottom: 5.5rem;
  left: 2rem;
  z-index: 50;
  max-width: 280px;
  padding: 0.8rem 1rem;
  background: rgba(8, 8, 16, 0.85);
  border: 1px solid rgba(253, 184, 19, 0.2);
  border-radius: 0.5rem;
  font-size: 0.7rem;
  font-weight: 300;
  line-height: 1.6;
  letter-spacing: 0.03em;
  color: rgba(255, 255, 255, 0.55);
  opacity: 0;
  pointer-events: none;
  transform: translateY(6px);
  transition: opacity 0.4s ease, transform 0.4s ease;
}

.scale-annotation strong {
  color: rgba(253, 184, 19, 0.9);
  font-weight: 500;
}

.scale-annotation.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ── G1: Mass callout ────────────────────────────────────────────
   Auto-dismissing callout shown once when True Scale activates.
   REVERT: remove #massMassCallout from DOM or delete showMassCallout() call. */
.mass-callout {
  position: fixed;
  bottom: 9rem;
  left: 2rem;
  z-index: 50;
  max-width: 260px;
  padding: 0.65rem 0.9rem;
  background: rgba(8, 8, 16, 0.9);
  border: 1px solid rgba(253, 184, 19, 0.25);
  border-radius: 0.4rem;
  font-size: 0.68rem;
  font-weight: 300;
  line-height: 1.55;
  letter-spacing: 0.03em;
  color: rgba(255, 255, 255, 0.6);
  opacity: 0;
  transform: translateY(6px);
  pointer-events: none;
  transition: opacity 0.4s ease, transform 0.4s ease;
}

.mass-callout.visible {
  opacity: 1;
  transform: translateY(0);
}

.mass-callout.dismiss {
  opacity: 0;
  transform: translateY(-4px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

/* ── G2: True-Scale small planet labels ──────────────────────────
   Vertical line + floating name above small inner planets.
   ALL rules scoped to [data-scale-mode="true"] — removing that
   attribute is a complete revert with zero residual styling.      */
.scale-label-line {
  display: none; /* hidden by default; shown only in true-scale via selector below */
  position: absolute;
  bottom: calc(100% + 4px);
  left: 50%;
  transform: translateX(-50%);
  width: 1px;
  height: 48px;
  pointer-events: none;
}

.scale-label-line::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(to top, var(--accent, rgba(255,255,255,0.3)), transparent);
  opacity: 0.35;
}

.scale-label-name {
  position: absolute;
  bottom: 100%;
  left: 50%;
  transform: translateX(-50%);
  white-space: nowrap;
  font-size: 0.55rem;
  font-weight: 400;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: rgba(255, 255, 255, 0.45);
  margin-bottom: 4px;
}

/* Only show labels when true-scale mode is active */
#solarTrack[data-scale-mode="true"] .scale-label-line {
  display: block;
}

/* Ensure body-item has relative positioning for absolute label placement */
#solarTrack[data-scale-mode="true"] .body-item {
  position: relative;
  overflow: visible;
}

@media (prefers-reduced-motion: reduce) {
  .mass-callout {
    transition: none;
  }
}

/* B1: Orb size transition when switching modes */
.orb {
  transition: transform 0.4s cubic-bezier(0.34, 1.56, 0.64, 1),
              width 0.8s cubic-bezier(0.25, 1, 0.5, 1),
              height 0.8s cubic-bezier(0.25, 1, 0.5, 1);
}

/* ── B6: Planet hover preview card ──────────────────────────── */
.planet-preview-card {
  position: fixed;
  z-index: 60;
  pointer-events: none;
  opacity: 0;
  transform: translateY(10px) scale(0.95);
  transition: opacity 0.25s ease, transform 0.25s cubic-bezier(0.34, 1.56, 0.64, 1);
  width: 200px;
}

.planet-preview-card.visible {
  opacity: 1;
  transform: translateY(0) scale(1);
}

.planet-preview-inner {
  background: rgba(8, 8, 16, 0.88);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 0.75rem;
  padding: 1rem;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.planet-preview-name {
  font-size: 1.1rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--preview-accent, #fff);
  margin-bottom: 0.5rem;
  line-height: 1;
}

.planet-preview-fact {
  font-size: 0.68rem;
  font-weight: 300;
  letter-spacing: 0.04em;
  color: rgba(255, 255, 255, 0.45);
  line-height: 1.5;
}

.planet-preview-bar {
  height: 1px;
  background: var(--preview-accent, rgba(255,255,255,0.2));
  opacity: 0.3;
  margin: 0.6rem 0;
}

/* ── B7: Keyboard nav focus ring ─────────────────────────────── */
.body-item.keyboard-focused {
  outline: none;
}

.body-item.keyboard-focused .orbit-ring {
  opacity: 1;
  transform: scale(1);
  border-color: var(--kb-accent, rgba(255, 255, 255, 0.5));
  box-shadow: 0 0 12px var(--kb-accent, rgba(255, 255, 255, 0.2));
  animation: orbitSpinHover 20s linear infinite;
}

.body-item.keyboard-focused .body-label {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

/* Keyboard nav hint */
.keyboard-hint {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  z-index: 50;
  font-size: 0.6rem;
  font-weight: 300;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: rgba(255, 255, 255, 0.2);
  opacity: 0;
  transition: opacity 0.4s ease;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.keyboard-hint kbd {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.1rem 0.35rem;
  border: 1px solid rgba(255, 255, 255, 0.15);
  border-radius: 3px;
  font-family: var(--font);
  font-size: 0.6rem;
  color: rgba(255, 255, 255, 0.3);
}

/* ── B2: Live orbit arc on planet labels ─────────────────────── */
.live-arc-wrap {
  margin-top: 0.3rem;
}

.live-orbit-arc {
  width: 32px;
  height: 32px;
  display: block;
  margin: 0 auto;
}

.live-distance {
  display: block;
  font-size: 0.58rem;
  font-weight: 300;
  letter-spacing: 0.06em;
  color: rgba(255, 255, 255, 0.28);
  margin-top: 0.2rem;
  text-align: center;
}

/* ── B4: APOD Widget ─────────────────────────────────────────── */
.apod-widget {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  z-index: 50;
  width: 200px;
  opacity: 0;
  transform: translateY(8px);
  transition: opacity 0.5s ease, transform 0.5s ease;
  pointer-events: none;
}

.apod-widget.visible {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

.apod-widget-inner {
  background: rgba(8, 8, 16, 0.82);
  border: 1px solid rgba(255, 255, 255, 0.09);
  border-radius: 0.75rem;
  overflow: hidden;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.apod-widget-header {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 0.5rem;
  padding: 0.75rem 0.85rem 0.4rem;
}

.apod-widget-eyebrow {
  font-size: 0.55rem;
  font-weight: 400;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: rgba(255, 255, 255, 0.3);
  flex: 1;
  line-height: 1.3;
}

.apod-widget-date {
  font-size: 0.55rem;
  font-weight: 300;
  color: rgba(255, 255, 255, 0.2);
  white-space: nowrap;
}

.apod-widget-thumb {
  width: 100%;
  height: 110px;
  background-size: cover;
  background-position: center;
  cursor: pointer;
  transition: transform 0.4s ease;
}

.apod-widget-thumb:hover { transform: scale(1.03); }

.apod-widget-thumb--video {
  background: rgba(255,255,255,0.04);
  display: flex;
  align-items: center;
  justify-content: center;
  color: rgba(255,255,255,0.4);
  cursor: pointer;
}
.apod-widget-thumb--video svg { width: 28px; height: 28px; }

.apod-widget-title {
  font-size: 0.68rem;
  font-weight: 400;
  line-height: 1.4;
  letter-spacing: 0.02em;
  color: rgba(255, 255, 255, 0.65);
  padding: 0.5rem 0.85rem 0.4rem;
}

.apod-widget-expand {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  padding: 0.5rem 0.85rem 0.7rem;
  font-family: var(--font);
  font-size: 0.6rem;
  font-weight: 400;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: rgba(255, 255, 255, 0.3);
  background: transparent;
  border: none;
  border-top: 1px solid rgba(255, 255, 255, 0.06);
  cursor: pointer;
  transition: color 0.2s ease;
}

.apod-widget-expand:hover { color: rgba(255, 255, 255, 0.75); }
.apod-widget-expand svg { width: 14px; height: 14px; }

/* ── APOD Lightbox ───────────────────────────────────────────── */
.apod-lightbox {
  position: fixed;
  inset: 0;
  z-index: 500;
  display: flex;
  align-items: flex-start;
  justify-content: center;
  padding: 4rem 1.5rem 2rem;
  overflow-y: auto;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s ease;
}

.apod-lightbox.open {
  opacity: 1;
  pointer-events: auto;
}

.apod-lightbox-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(2, 2, 8, 0.94);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.apod-lightbox-inner {
  position: relative;
  z-index: 1;
  max-width: min(860px, 94vw);
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.apod-lightbox-close {
  position: fixed;
  top: 1.5rem;
  right: 1.5rem;
  z-index: 501;
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(255,255,255,0.08);
  border: 1px solid rgba(255,255,255,0.2);
  border-radius: 50%;
  cursor: pointer;
  color: rgba(255,255,255,0.8);
  transition: color 0.2s, background 0.2s;
}
.apod-lightbox-close:hover { color: #fff; background: rgba(255,255,255,0.15); }
.apod-lightbox-close svg { width: 18px; height: 18px; }

.apod-lightbox-media { border-radius: 8px; overflow: hidden; }

.apod-lightbox-img {
  display: block;
  width: 100%;
  height: auto;
  max-height: 65svh;
  object-fit: contain;
  background: #04040c;
}

.apod-lightbox-video {
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;
}

.apod-lightbox-text { display: flex; flex-direction: column; gap: 0.6rem; }

.apod-lightbox-date {
  font-size: 0.65rem;
  font-weight: 300;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: rgba(255,255,255,0.3);
}

.apod-lightbox-title {
  font-size: clamp(1rem, 2.5vw, 1.4rem);
  font-weight: 500;
  color: #fff;
  letter-spacing: 0.04em;
  margin: 0;
}

.apod-lightbox-explanation {
  font-size: 0.85rem;
  font-weight: 300;
  line-height: 1.8;
  color: rgba(255,255,255,0.55);
}

.apod-lightbox-credit {
  font-size: 0.65rem;
  color: rgba(255,255,255,0.22);
  letter-spacing: 0.08em;
}

.apod-lightbox-video-wrap {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
}

.apod-lightbox-video-placeholder {
  width: 100%;
  aspect-ratio: 16 / 9;
  background: rgba(255,255,255,0.04);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.apod-video-link {
  font-size: 0.8rem;
  font-weight: 400;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: rgba(255,255,255,0.5);
  text-decoration: none;
  border: 1px solid rgba(255,255,255,0.2);
  padding: 0.5rem 1.25rem;
  border-radius: 2rem;
  transition: color 0.2s ease, border-color 0.2s ease;
}
.apod-video-link:hover { color: #fff; border-color: rgba(255,255,255,0.5); }

/* ── Reduced motion ──────────────────────────────────────────── */
@media (prefers-reduced-motion: reduce) {
  .orbit-ring,
  .orb,
  .orb-glow,
  .orb-core,
  .orb-core::after,
  .body-label,
  .scroll-hint svg,
  .scale-toggle,
  .live-orbit-arc circle {
    animation: none !important;
    transition: none !important;
  }
}

/* ── Moon system ─────────────────────────────────────────────────
   All rules gated behind [data-moons-enabled] on #solarTrack.
   To disable the entire feature: remove the data-moons-enabled
   attribute from #solarTrack in solar-system.html — one attribute,
   zero residual styling.
   ─────────────────────────────────────────────────────────────── */

/* Ensure body-items don't clip moon orbits */
[data-moons-enabled] .body-item {
  overflow: visible;
}

/* Moon system wrapper — zero-size anchor centred on the orb */
[data-moons-enabled] .moon-system {
  position: absolute;
  /* Sit at the centre of body-item (which is flex-centred) */
  top: 50%;
  left: 50%;
  width: 0;
  height: 0;
  pointer-events: none;
  overflow: visible;
}

/* Moon orbit track — a disc that rotates around the anchor point.
   top/left: 50% places the top-left corner at body-item centre;
   margin offsets recentre it. The rotation animation spins the whole
   disc so the dot at top: 0 traces the orbit path. */
[data-moons-enabled] .moon-orbit {
  position: absolute;
  border-radius: 50%;
  border: none;
  top: 50%;
  left: 50%;
  /* Negative margins of half the disc size to centre it.
     Overridden per-orbit using custom margin properties: */
  margin-top: calc(var(--orbit-r) * -1);
  margin-left: calc(var(--orbit-r) * -1);
  transform-origin: 50% 50%;
  animation: moonOrbit var(--moon-period, 8s) linear infinite;
  animation-direction: var(--moon-direction, normal);
}

/* The moon dot sits at the top of the orbit disc */
[data-moons-enabled] .moon {
  position: absolute;
  border-radius: 50%;
  width: var(--moon-size, 3px);
  height: var(--moon-size, 3px);
  background: var(--moon-colour, rgba(255, 255, 255, 0.7));
  /* Position dot at the top-centre of the orbit disc */
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  box-shadow: 0 0 3px var(--moon-colour, rgba(255, 255, 255, 0.5));
}

@keyframes moonOrbit {
  from { transform: rotate(0deg); }
  to   { transform: rotate(360deg); }
}

/* ── Per-moon orbit sizes and periods ─────────────────────────── */

/* Earth: The Moon — orbit radius 38px from orb centre (orb=54px, disc=76px) */
[data-moons-enabled] .moon-orbit--earth-moon {
  --moon-period: 10s;
  --orbit-r: 38px;
  width: 76px;
  height: 76px;
}
[data-moons-enabled] .moon--earth-moon {
  --moon-size: 4px;
  --moon-colour: rgba(210, 210, 200, 0.85);
}

/* Mars: Phobos — tiny, very close, fast orbit (orb=40px, disc=56px) */
[data-moons-enabled] .moon-orbit--phobos {
  --moon-period: 4s;
  --orbit-r: 28px;
  width: 56px;
  height: 56px;
}
[data-moons-enabled] .moon--phobos {
  --moon-size: 2px;
  --moon-colour: rgba(180, 140, 110, 0.8);
}

/* Mars: Deimos — slightly further out, slower */
[data-moons-enabled] .moon-orbit--deimos {
  --moon-period: 7s;
  --orbit-r: 35px;
  width: 70px;
  height: 70px;
  animation-delay: -3.5s;
}
[data-moons-enabled] .moon--deimos {
  --moon-size: 2px;
  --moon-colour: rgba(180, 140, 110, 0.65);
}

/* Jupiter: Io — closest Galilean, fast, warm yellow.
   Orbit radius 68px clears the True Scale orb radius (119px / 2 = 59.5px). */
[data-moons-enabled] .moon-orbit--io {
  --moon-period: 6s;
  --orbit-r: 68px;
  width: 136px;
  height: 136px;
}
[data-moons-enabled] .moon--io {
  --moon-size: 3px;
  --moon-colour: rgba(235, 205, 120, 0.9);
}

/* Jupiter: Europa — icy blue-white */
[data-moons-enabled] .moon-orbit--europa {
  --moon-period: 9s;
  --orbit-r: 82px;
  width: 164px;
  height: 164px;
  animation-delay: -2s;
}
[data-moons-enabled] .moon--europa {
  --moon-size: 3px;
  --moon-colour: rgba(190, 215, 235, 0.85);
}

/* Jupiter: Ganymede — largest moon in the solar system */
[data-moons-enabled] .moon-orbit--ganymede {
  --moon-period: 14s;
  --orbit-r: 98px;
  width: 196px;
  height: 196px;
  animation-delay: -5s;
}
[data-moons-enabled] .moon--ganymede {
  --moon-size: 4px;
  --moon-colour: rgba(170, 165, 155, 0.8);
}

/* Jupiter: Callisto — outermost Galilean, darkest, slowest */
[data-moons-enabled] .moon-orbit--callisto {
  --moon-period: 22s;
  --orbit-r: 116px;
  width: 232px;
  height: 232px;
  animation-delay: -8s;
}
[data-moons-enabled] .moon--callisto {
  --moon-size: 4px;
  --moon-colour: rgba(130, 120, 115, 0.7);
}

/* Saturn: Titan — large, orange-hued. Orbit sits in the gap between mid and outer rings.
   Aesthetic mode rings: inner=47px, mid=59px, outer=72px from orb centre.
   True Scale mode rings: inner=63px, mid=80px, outer=97px from orb centre.
   85px radius clears the inner ring in both modes. */
[data-moons-enabled] .moon-orbit--titan {
  --moon-period: 18s;
  --orbit-r: 85px;
  width: 170px;
  height: 170px;
}
[data-moons-enabled] .moon--titan {
  --moon-size: 4px;
  --moon-colour: rgba(215, 170, 90, 0.85);
}

/* Neptune: Triton — retrograde orbit (reverse), cold blue-grey (orb=60px) */
[data-moons-enabled] .moon-orbit--triton {
  --moon-period: 12s;
  --moon-direction: reverse;
  --orbit-r: 49px;
  width: 98px;
  height: 98px;
}
[data-moons-enabled] .moon--triton {
  --moon-size: 3px;
  --moon-colour: rgba(160, 185, 215, 0.8);
}

/* ── Moon reduced-motion override ────────────────────────────── */
@media (prefers-reduced-motion: reduce) {
  [data-moons-enabled] .moon-orbit {
    animation: none !important;
  }
  /* Dots remain visible but static — placed at top of orbit */
}

/* ── Kuiper Belt ─────────────────────────────────────────────────
   Same pattern as Asteroid Belt. Icy blue-grey palette, slightly
   more diffuse. To disable: remove data-belt-enabled from #solarTrack
   (shares the same gate as the Asteroid Belt).
   ─────────────────────────────────────────────────────────────── */

.kuiper-belt {
  display: none;
}

[data-belt-enabled] .kuiper-belt {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  position: relative;
  flex-shrink: 0;
  width: 16vw;
  min-width: 120px;
  max-width: 220px;
  margin-right: 0;
  cursor: default;
}

[data-belt-enabled] .kuiper-canvas {
  display: block;
  width: 100%;
  height: 80vh;
}

[data-belt-enabled] .kuiper-label {
  margin-top: 1rem;
  white-space: nowrap;
  font-size: 0.55rem;
  font-weight: 400;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: rgba(255, 255, 255, 0.2);
  pointer-events: none;
  text-align: center;
}

/* ── Frost Line ──────────────────────────────────────────────────
   Sits between Mars and the Asteroid Belt (~2.7 AU).
   Icy blue-white line — contrasts with the amber heliopause.
   Same 40px wide hit area pattern as the heliopause.
   ─────────────────────────────────────────────────────────────── */
.frost-line {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  position: relative;
  width: 40px;
  height: 80vh;
  margin-right: 4vw;
  cursor: default;
}

.frost-line-rule {
  width: 1px;
  height: 100%;
  background: linear-gradient(
    to bottom,
    transparent 0%,
    rgba(160, 220, 255, 0.12) 10%,
    rgba(160, 220, 255, 0.45) 40%,
    rgba(160, 220, 255, 0.45) 60%,
    rgba(160, 220, 255, 0.12) 90%,
    transparent 100%
  );
  position: relative;
}

.frost-line-rule::after {
  content: '';
  position: absolute;
  inset: 0 -6px;
  background: linear-gradient(
    to bottom,
    transparent 0%,
    rgba(160, 220, 255, 0.04) 15%,
    rgba(160, 220, 255, 0.10) 40%,
    rgba(160, 220, 255, 0.10) 60%,
    rgba(160, 220, 255, 0.04) 85%,
    transparent 100%
  );
  pointer-events: none;
}

.frost-line-label {
  position: absolute;
  top: calc(50% - 48px);
  left: 50%;
  transform: translateX(-50%) rotate(-90deg);
  transform-origin: center center;
  white-space: nowrap;
  font-size: 0.5rem;
  font-weight: 400;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: rgba(160, 220, 255, 0.4);
  pointer-events: none;
}

/* ── Oort Cloud ──────────────────────────────────────────────────
   Ultra-sparse, ultra-faint dot field at the very end of the track.
   Much dimmer than the Kuiper Belt — evokes infinite cold distance.
   ─────────────────────────────────────────────────────────────── */
.oort-cloud {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  position: relative;
  width: 20vw;
  min-width: 160px;
  max-width: 280px;
  margin-right: 15vw; /* generous right padding so track feels it ends in infinity */
  cursor: default;
}

.oort-canvas {
  display: block;
  width: 100%;
  height: 80vh;
}

.oort-label {
  margin-top: 1rem;
  white-space: nowrap;
  font-size: 0.55rem;
  font-weight: 400;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: rgba(255, 255, 255, 0.12);
  pointer-events: none;
  text-align: center;
}

/* ── Heliopause ──────────────────────────────────────────────────
   Thin vertical amber line — the boundary where the Sun's solar
   wind yields to interstellar space (~120 AU). Same height as
   the belt canvases for visual consistency.
   ─────────────────────────────────────────────────────────────── */
.heliopause {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  position: relative;
  margin-right: 8vw;
  height: 80vh;
  /* Wide invisible hit area so the 1px line is easy to hover */
  width: 40px;
  cursor: default;
}

.heliopause-line {
  width: 1px;
  height: 100%;
  background: linear-gradient(
    to bottom,
    transparent 0%,
    rgba(253, 184, 19, 0.15) 10%,
    rgba(253, 184, 19, 0.5)  40%,
    rgba(253, 184, 19, 0.5)  60%,
    rgba(253, 184, 19, 0.15) 90%,
    transparent 100%
  );
  position: relative;
}

/* Subtle glow behind the line */
.heliopause-line::after {
  content: '';
  position: absolute;
  inset: 0 -6px;
  background: linear-gradient(
    to bottom,
    transparent 0%,
    rgba(253, 184, 19, 0.04) 15%,
    rgba(253, 184, 19, 0.12) 40%,
    rgba(253, 184, 19, 0.12) 60%,
    rgba(253, 184, 19, 0.04) 85%,
    transparent 100%
  );
  pointer-events: none;
}

.heliopause-label {
  position: absolute;
  bottom: calc(50% - 48px);
  left: 50%;
  transform: translateX(-50%) rotate(-90deg);
  transform-origin: center center;
  white-space: nowrap;
  font-size: 0.5rem;
  font-weight: 400;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: rgba(253, 184, 19, 0.45);
  pointer-events: none;
}

/* ── Voyager dots ────────────────────────────────────────────────
   Tiny glowing dots representing humanity's furthest probes.
   ─────────────────────────────────────────────────────────────── */
.voyager-dot {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  position: relative;
  margin-right: 6vw;
  cursor: default;
}

.voyager-pip {
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: rgba(180, 210, 240, 0.9);
  box-shadow:
    0 0 4px  rgba(180, 210, 240, 0.8),
    0 0 10px rgba(180, 210, 240, 0.4),
    0 0 20px rgba(180, 210, 240, 0.15);
  animation: voyagerPulse 3s ease-in-out infinite;
}

@keyframes voyagerPulse {
  0%, 100% { box-shadow: 0 0 4px rgba(180,210,240,0.8), 0 0 10px rgba(180,210,240,0.4), 0 0 20px rgba(180,210,240,0.15); }
  50%       { box-shadow: 0 0 6px rgba(180,210,240,1.0), 0 0 16px rgba(180,210,240,0.6), 0 0 32px rgba(180,210,240,0.2); }
}

.voyager-label {
  margin-top: 0.6rem;
  white-space: nowrap;
  font-size: 0.5rem;
  font-weight: 400;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: rgba(180, 210, 240, 0.4);
  pointer-events: none;
  text-align: center;
}

/* Voyager spacecraft image inside hover card */
.voyager-preview-img {
  display: block;
  width: 100%;
  height: 90px;
  object-fit: contain;
  object-position: center;
  margin-bottom: 0.6rem;
  opacity: 0.85;
  filter: brightness(0.9);
}

/* Live distance ticker inside Voyager hover card */
.voyager-dist-live {
  display: block;
  margin-top: 0.25rem;
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.04em;
  color: rgba(180, 210, 240, 0.9);
  font-variant-numeric: tabular-nums;
}

@media (prefers-reduced-motion: reduce) {
  .voyager-pip {
    animation: none !important;
  }
}

/* ── Asteroid Belt ───────────────────────────────────────────────
   Gated behind [data-belt-enabled] on #solarTrack.
   To disable: remove data-belt-enabled from #solarTrack in solar-system.html.
   ─────────────────────────────────────────────────────────────── */

/* Hidden by default — only shown when gate is active */
.asteroid-belt {
  display: none;
}

[data-belt-enabled] .asteroid-belt {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  position: relative;
  flex-shrink: 0;
  width: 12vw;
  min-width: 100px;
  max-width: 180px;
  margin-right: 8vw;
  cursor: default;
}

[data-belt-enabled] .belt-canvas {
  display: block;
  width: 100%;
  height: 80vh;
}

[data-belt-enabled] .belt-label {
  margin-top: 1rem;
  white-space: nowrap;
  font-size: 0.55rem;
  font-weight: 400;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: rgba(255, 255, 255, 0.25);
  pointer-events: none;
  text-align: center;
}