html.intro-active {
  overflow: hidden;
}
.nexus-intro {
  position: fixed;
  inset: 0;
  z-index: 10000;
  display: grid;
  place-items: center;
  overflow: hidden;
  background: var(--bg);
  color: var(--text);
  opacity: 1;
  transition: opacity var(--intro-reveal, 500ms) ease;
  cursor: pointer;
}
.intro-center {
  width: min(460px, calc(100% - 48px));
  text-align: center;
  transform: translateY(-12px);
  position: relative;
}
.intro-headline {
  display: grid;
  align-items: center;
  min-height: 62px;
  font-family: var(--sans, system-ui);
  font-size: clamp(24px, 5.4vw, 42px);
  font-weight: 400;
  letter-spacing: 0.19em;
  line-height: 1.25;
}
.intro-headline > span {
  grid-area: 1/1;
  transition:
    opacity 0.3s ease,
    transform 0.3s ease;
  white-space: nowrap;
}
.intro-brand {
  color: var(--text);
  text-shadow: 0 0 25px var(--accent-soft);
  animation: intro-light 1.5s ease-in-out both;
}
.intro-online {
  opacity: 0;
  transform: translateY(5px);
  font-size: 0.78em;
  letter-spacing: 0.14em;
}
.intro-welcome {
  margin-top: 14px;
  min-height: 18px;
  font: 400 12px/1.5 var(--mono, monospace);
  letter-spacing: 0.25em;
  color: var(--muted);
  opacity: 0;
  transform: translateY(5px);
  transition:
    opacity 0.35s ease,
    transform 0.35s ease;
}
.intro-progress {
  display: flex;
  align-items: center;
  gap: 14px;
  width: min(280px, 100%);
  margin: 26px auto 0;
  transition: opacity 0.25s ease;
}
.intro-track {
  height: 2px;
  flex: 1;
  background: var(--accent-soft);
  border-radius: 2px;
  overflow: visible;
}
.intro-track > span {
  display: block;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, var(--line-strong), var(--accent));
  transform: scaleX(0);
  transform-origin: left;
  border-radius: 2px;
  box-shadow: 0 0 12px var(--accent-glow);
}
.intro-percent {
  width: 4ch;
  text-align: right;
  font: 10px/1 var(--mono, monospace);
  color: var(--muted);
  font-variant-numeric: tabular-nums;
}
.intro-controls {
  position: absolute;
  bottom: max(24px, env(safe-area-inset-bottom));
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  gap: 12px;
  white-space: nowrap;
}
.intro-controls button {
  padding: 10px 16px;
  min-height: 40px;
  background: transparent;
  border: 1px solid transparent;
  border-radius: 7px;
  color: var(--muted);
  font: 11px var(--sans, system-ui);
  letter-spacing: 0.04em;
}
.intro-controls button:hover,
.intro-controls button:focus-visible {
  color: var(--text);
  border-color: var(--line);
  outline: none;
}
.nexus-intro[data-phase='online'] .intro-brand,
.nexus-intro[data-phase='welcome'] .intro-brand {
  opacity: 0;
  transform: translateY(-5px);
}
.nexus-intro[data-phase='online'] .intro-online,
.nexus-intro[data-phase='welcome'] .intro-online {
  opacity: 1;
  transform: none;
}
.nexus-intro[data-phase='online'] .intro-progress,
.nexus-intro[data-phase='welcome'] .intro-progress {
  opacity: 0;
}
.nexus-intro[data-phase='welcome'] .intro-welcome {
  opacity: 1;
  transform: none;
}
.nexus-intro[data-phase='exit'] {
  opacity: 0;
  pointer-events: none;
}
.intro-settings {
  border: 1px solid var(--line);
  border-radius: 10px;
  background: var(--surface);
  padding: 14px;
  max-width: 560px;
}
.intro-settings label {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 13px;
}
.intro-settings input {
  width: 16px;
  height: 16px;
  accent-color: var(--accent);
}
.intro-settings p {
  font-size: 12px;
  line-height: 1.5;
  color: var(--muted);
}
.intro-settings button {
  min-height: var(--control-height);
  padding: var(--button-padding);
  margin-top: 12px;
  color: var(--text);
  background: var(--button-bg);
  border: 1px solid var(--line);
  border-radius: var(--button-radius);
}
.intro-settings button:hover {
  border-color: var(--accent);
}
#introSettingStatus:empty {
  display: none;
}
@keyframes intro-light {
  0% {
    opacity: 0.35;
    text-shadow: 0 0 0 transparent;
  }
  65% {
    opacity: 1;
    text-shadow: 0 0 30px var(--accent-glow);
  }
  100% {
    opacity: 1;
    text-shadow: 0 0 18px var(--accent-soft);
  }
}
@media (prefers-reduced-motion: reduce) {
  .nexus-intro,
  .nexus-intro * {
    animation: none !important;
    transition: none !important;
  }
}

.nexus-intro {
  outline: none;
}
.nexus-intro[data-phase='online'] .intro-brand,
.nexus-intro[data-phase='welcome'] .intro-brand {
  animation: none;
}

.intro-emblem {
  display: block;
  width: 110px;
  height: auto;
  margin: 0 auto 26px;
  opacity: 0.9;
}

.intro-settings label + label {
  margin-top: 12px;
}