/**
 * Canonical first-paint loader styles shared by HTML splash and React loaders.
 * The blocking index.html script selects gpnDark/gpnDefault before first paint;
 * prefers-color-scheme remains the fallback for a user's first visit.
 */
:root {
  --boot-loader-bg: #f3f3f4;
  --boot-loader-fg: #231f20;
  --boot-loader-accent: #2d292a;
  --boot-loader-line: rgba(35, 31, 32, 0.12);
  --boot-loader-glow: rgba(35, 31, 32, 0.08);
  --boot-loader-logo-size: clamp(44px, 8vw, 54px);
  --boot-loader-stage-size: clamp(96px, 18vw, 116px);
  --boot-loader-signal-size: clamp(72px, 18vw, 92px);
  --boot-loader-gap: 22px;
  --boot-loader-orbit-duration: 2.4s;
  --boot-loader-signal-duration: 1.4s;
}

html[data-boot-theme='gpnDark'] {
  --boot-loader-bg: #121212;
  --boot-loader-fg: #e0e0e0;
  --boot-loader-accent: #f1f1f1;
  --boot-loader-line: rgba(224, 224, 224, 0.14);
  --boot-loader-glow: rgba(255, 255, 255, 0.1);
}

@media (prefers-color-scheme: dark) {
  html:not([data-boot-theme]) {
    --boot-loader-bg: #121212;
    --boot-loader-fg: #e0e0e0;
    --boot-loader-accent: #f1f1f1;
    --boot-loader-line: rgba(224, 224, 224, 0.14);
    --boot-loader-glow: rgba(255, 255, 255, 0.1);
  }
}

/* Shared structure keeps HTML-first → React handoff visually identical. */
.boot-loader {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--boot-loader-gap);
  color: var(--boot-loader-fg);
  background-color: var(--boot-loader-bg);
}

.boot-loader__symbols {
  position: absolute;
  overflow: hidden;
  width: 0;
  height: 0;
}

.boot-loader__visual {
  position: relative;
  display: grid;
  width: var(--boot-loader-stage-size);
  height: var(--boot-loader-stage-size);
  flex-shrink: 0;
  place-items: center;
  border-radius: 50%;
  background: radial-gradient(circle, var(--boot-loader-glow) 0, transparent 68%);
}

.boot-loader__visual::before,
.boot-loader__visual::after {
  position: absolute;
  border: 1px solid var(--boot-loader-line);
  border-radius: 50%;
  content: '';
}

.boot-loader__visual::before {
  inset: 0;
  border-top-color: var(--boot-loader-accent);
  border-right-color: color-mix(in srgb, var(--boot-loader-accent) 42%, transparent);
}

.boot-loader__visual::after {
  inset: 12%;
  border-bottom-color: var(--boot-loader-accent);
}

.boot-loader--indeterminate .boot-loader__visual::before {
  animation: boot-loader-orbit var(--boot-loader-orbit-duration) linear infinite;
}

.boot-loader__logo {
  z-index: 1;
  width: var(--boot-loader-logo-size);
  height: var(--boot-loader-logo-size);
  fill: var(--boot-loader-fg);
}

.boot-loader__signal {
  position: relative;
  overflow: hidden;
  width: var(--boot-loader-signal-size);
  height: 3px;
  flex-shrink: 0;
  border-radius: 999px;
  background: var(--boot-loader-line);
}

.boot-loader__signal::after {
  position: absolute;
  inset: 0 auto 0 0;
  width: 36%;
  border-radius: inherit;
  background: var(--boot-loader-accent);
  content: '';
  animation: boot-loader-signal var(--boot-loader-signal-duration) ease-in-out infinite;
}

#app-splash {
  transition: opacity 0.3s ease;
}

@keyframes boot-loader-orbit {
  to {
    transform: rotate(360deg);
  }
}

@keyframes boot-loader-signal {
  from {
    transform: translateX(-120%);
  }

  to {
    transform: translateX(380%);
  }
}

@media (prefers-reduced-motion: reduce) {
  #app-splash {
    transition: none;
  }

  .boot-loader--indeterminate .boot-loader__visual::before,
  .boot-loader__signal::after {
    animation: none;
  }

  .boot-loader__signal::after {
    width: 100%;
    opacity: 0.45;
    transform: none;
  }
}