:root {
  --bg: #05060c;
  --ink: #e9eeff;
  --muted: #8b93b6;
  --accent: #7aa2ff;
  --panel: rgba(14, 18, 34, 0.62);
  --panel-line: rgba(140, 165, 255, 0.18);
  --shadow: 0 18px 50px rgba(0, 0, 0, 0.55);
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  height: 100%;
  overflow: hidden;
  background: var(--bg);
  color: var(--ink);
  font-family: "Segoe UI", system-ui, -apple-system, Roboto, Helvetica, Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

#scene {
  position: fixed;
  inset: 0;
  display: block;
  width: 100%;
  height: 100%;
  touch-action: none;
  cursor: grab;
}
#scene.grabbing { cursor: grabbing; }
#scene.pointing { cursor: pointer; }

.hidden { display: none !important; }

/* ---- intro ---- */
.overlay {
  position: fixed;
  inset: 0;
  display: grid;
  place-items: center;
  z-index: 30;
  background: radial-gradient(120% 90% at 50% 32%, rgba(6, 8, 18, 0.12), rgba(3, 4, 10, 0.72));
  animation: fade 0.6s ease;
}
@keyframes fade { from { opacity: 0; } to { opacity: 1; } }

.intro-inner {
  text-align: center;
  padding: 24px;
  max-width: 460px;
  width: 100%;
}

.title {
  display: inline-block;
  margin: 0;
  white-space: nowrap;
  font-size: clamp(48px, 13vw, 92px);
  font-weight: 200;
  letter-spacing: 0.26em;
  text-indent: 0.26em;
  background: linear-gradient(180deg, #ffffff, #9fb8ff 70%, #6f86d6);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  filter: drop-shadow(0 0 26px rgba(122, 162, 255, 0.45));
}

.tagline {
  margin: 6px 0 30px;
  color: var(--muted);
  font-size: clamp(14px, 3.6vw, 17px);
  letter-spacing: 0.02em;
}

.seedrow {
  display: flex;
  gap: 8px;
  margin: 0 auto 14px;
  max-width: 340px;
}

#seedInput {
  flex: 1;
  min-width: 0;
  padding: 13px 16px;
  border-radius: 12px;
  border: 1px solid var(--panel-line);
  background: rgba(10, 13, 26, 0.7);
  color: var(--ink);
  font-size: 16px;
  letter-spacing: 0.04em;
  outline: none;
  transition: border-color 0.2s, box-shadow 0.2s;
}
#seedInput:focus {
  border-color: rgba(122, 162, 255, 0.6);
  box-shadow: 0 0 0 3px rgba(122, 162, 255, 0.16);
}
#seedInput::placeholder { color: #5b658a; }

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  color: var(--ink);
  -webkit-tap-highlight-color: transparent;
}

.icon {
  width: 48px;
  border-radius: 12px;
  border: 1px solid var(--panel-line);
  background: rgba(10, 13, 26, 0.7);
  font-size: 20px;
  line-height: 1;
  transition: transform 0.3s, background 0.2s;
}
.icon:hover { background: rgba(24, 30, 54, 0.9); }
.icon:active { transform: rotate(180deg); }

.primary {
  width: 100%;
  max-width: 340px;
  padding: 14px 18px;
  border-radius: 12px;
  font-size: 17px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  background: linear-gradient(180deg, rgba(122, 162, 255, 0.95), rgba(86, 120, 220, 0.95));
  box-shadow: 0 10px 30px rgba(86, 120, 220, 0.4);
  transition: transform 0.15s, box-shadow 0.2s, filter 0.2s;
}
.primary:hover { filter: brightness(1.08); box-shadow: 0 14px 38px rgba(86, 120, 220, 0.5); }
.primary:active { transform: translateY(1px) scale(0.99); }

.hint {
  margin: 22px 0 0;
  color: #5b658a;
  font-size: 13px;
  letter-spacing: 0.02em;
}

/* ---- hud ---- */
.hud {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 16px;
  padding-top: max(14px, env(safe-area-inset-top));
  pointer-events: none;
}
.hud > * { pointer-events: auto; }

.hud-left { display: flex; align-items: center; gap: 12px; }
.hud-right { display: flex; gap: 8px; }

.readout { display: flex; flex-direction: column; line-height: 1.3; }
.readout .scene {
  font-size: 14px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
}
.readout .muted { font-size: 12px; color: var(--muted); letter-spacing: 0.02em; }

.ghost {
  padding: 9px 14px;
  border-radius: 10px;
  background: var(--panel);
  border: 1px solid var(--panel-line);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--ink);
  box-shadow: var(--shadow);
  transition: background 0.2s, transform 0.12s;
}
.ghost:hover { background: rgba(28, 34, 60, 0.8); }
.ghost:active { transform: translateY(1px); }
.ghost.back { width: 42px; font-size: 22px; line-height: 1; padding: 4px 0; }

.jump {
  width: 132px;
  padding: 9px 12px;
  border-radius: 10px;
  background: var(--panel);
  border: 1px solid var(--panel-line);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  color: var(--ink);
  font-size: 13px;
  letter-spacing: 0.04em;
  outline: none;
  box-shadow: var(--shadow);
  transition: border-color 0.2s, width 0.2s;
}
.jump::placeholder { color: #6b749a; }
.jump:focus { border-color: rgba(122, 162, 255, 0.6); width: 168px; }
@media (max-width: 560px) { .jump { display: none; } }

.audio { display: inline-flex; align-items: center; justify-content: center; width: 40px; padding: 0; color: var(--ink); }
.audio .slash { display: none; }
.audio.muted { color: var(--muted); }
.audio.muted .wave { display: none; }
.audio.muted .slash { display: inline; }


/* ---- scan panel ---- */
.scan {
  position: fixed;
  z-index: 20;
  right: 16px;
  bottom: 16px;
  bottom: max(16px, env(safe-area-inset-bottom));
  width: min(340px, calc(100vw - 32px));
  padding: 18px 20px;
  border-radius: 16px;
  background: var(--panel);
  border: 1px solid var(--panel-line);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  box-shadow: var(--shadow);
  animation: rise 0.4s ease;
}
@keyframes rise { from { opacity: 0; transform: translateY(14px); } to { opacity: 1; transform: none; } }

.scan h2 {
  margin: 0 0 2px;
  font-size: 20px;
  font-weight: 500;
  letter-spacing: 0.04em;
}
.scan .sub { margin: 0 0 14px; color: var(--accent); font-size: 12px; letter-spacing: 0.18em; text-transform: uppercase; }

.scan .grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px 16px;
  margin-bottom: 14px;
}
.scan .stat { display: flex; flex-direction: column; }
.scan .stat .k { font-size: 11px; color: var(--muted); letter-spacing: 0.08em; text-transform: uppercase; }
.scan .stat .v { font-size: 15px; }

.scan .lore {
  margin: 0;
  padding-top: 12px;
  border-top: 1px solid var(--panel-line);
  color: #c4ccea;
  font-size: 13.5px;
  line-height: 1.55;
  font-style: italic;
}

/* ---- hover tip ---- */
.tip {
  position: fixed;
  z-index: 25;
  pointer-events: none;
  transform: translate(-50%, -150%);
  padding: 6px 11px;
  border-radius: 9px;
  background: rgba(8, 11, 22, 0.82);
  border: 1px solid var(--panel-line);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  font-size: 13px;
  letter-spacing: 0.03em;
  white-space: nowrap;
  box-shadow: var(--shadow);
}
.tip .small { color: var(--muted); font-size: 11px; }

/* ---- toast ---- */
.toast {
  position: fixed;
  z-index: 40;
  left: 50%;
  bottom: 34px;
  transform: translateX(-50%) translateY(10px);
  padding: 11px 18px;
  border-radius: 999px;
  background: rgba(14, 18, 34, 0.92);
  border: 1px solid var(--panel-line);
  font-size: 14px;
  letter-spacing: 0.03em;
  box-shadow: var(--shadow);
  opacity: 0;
  transition: opacity 0.25s, transform 0.25s;
}
.toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }

@media (max-width: 520px) {
  .scan { left: 16px; right: 16px; width: auto; }
  .readout .muted { max-width: 46vw; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
}