/* The one expressive moment: a large moon rising behind the sign-in card. */
body.auth {
  min-height: 100dvh;
  overflow: hidden;
  background:
    radial-gradient(70vmax 60vmax at 80% 20%, rgb(111 176 191 / 0.06), transparent 60%),
    var(--bg);
}

.signin {
  position: relative;
  min-height: 100dvh;
  display: grid;
  align-items: center;
  padding: max(var(--s-10), env(safe-area-inset-top)) var(--gutter) max(var(--s-10), env(safe-area-inset-bottom));
}

.signin__sky {
  position: absolute;
  inset: 0;
  overflow: hidden;
  pointer-events: none;
}

.signin__stars {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  animation: cluster-in 3s var(--ease-out) both;
}

.signin__cluster {
  position: absolute;
  width: min(72vmin, 680px);
  aspect-ratio: 1;
  right: max(-8vmin, calc((100vw - 1180px) / 2 - 8vmin));
  top: 4vh;
  animation: cluster-in 2s var(--ease-out) both;
  /* Soft edges, so the cluster never shows its box (even mid fly-in). */
  -webkit-mask: radial-gradient(closest-side, #000 72%, transparent);
  mask: radial-gradient(closest-side, #000 72%, transparent);
}

@keyframes cluster-in {
  from { opacity: 0; transform: scale(0.94); }
}

.signin__card {
  position: relative;
  width: min(100%, 1180px);
  margin: 0 auto;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--s-6);
  justify-items: start;
}

.signin__mark {
  display: flex;
  align-items: center;
  gap: var(--s-4);
}

/* The Nebula moon-companion head is the logo, inline before the wordmark. */
.signin__mark { align-items: center; }

.signin__companion {
  width: clamp(64px, 6.2vw, 96px);
  height: auto;
  flex-shrink: 0;
  filter: drop-shadow(0 10px 30px rgb(239 236 234 / 0.10));
  animation: companion-float 6s ease-in-out infinite;
}

@keyframes companion-float {
  50% { transform: translateY(-6px); }
}

.signin .wordmark {
  font-size: clamp(1.8rem, 1rem + 3.2vw, 3.6rem);
  letter-spacing: -0.01em;
}

.signin p {
  color: var(--dim);
  font-size: var(--t-lg);
  max-width: 44ch;
}

.signin__form { margin-top: var(--s-2); }

.signin__button {
  min-height: 52px;
  padding: 12px 24px;
  font-size: var(--t-md);
  box-shadow: none;
  transition: background-color var(--dur-move) var(--ease-out), color var(--dur-move) var(--ease-out),
              border-color var(--dur-move) var(--ease-out), box-shadow var(--dur-move) var(--ease-out);
}

.signin__button:hover,
.signin__button:focus-visible { box-shadow: none; }

/* ...and arrives in a soft fade to the page background instead of holding a
   frozen frame while Slack loads. */
.warp-veil {
  position: fixed; inset: 0; z-index: 60; display: grid; place-items: center;
  background: var(--bg); opacity: 0; pointer-events: none;
  transition: opacity 380ms cubic-bezier(0.4, 0, 1, 1);
}
.warp-veil__note { font-size: var(--t-sm); color: var(--dim); letter-spacing: .02em; opacity: 0; transition: opacity 500ms ease; }
body.warping .warp-veil { opacity: 1; transition-delay: 420ms; } /* fully dark by 0.8s, before the 0.95s hand-over */
body.warping .warp-veil__note { opacity: 1; transition-delay: 2s; }
@media (prefers-reduced-motion: reduce) { .warp-veil { display: none; } }

@media (max-width: 640px) {
  .signin { align-items: end; padding-bottom: max(var(--s-16), env(safe-area-inset-bottom)); }
  .signin__stars {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  animation: cluster-in 3s var(--ease-out) both;
}

.signin__cluster { width: 110vw; right: -34vw; top: 2vh; }
  .signin__mark { gap: var(--s-3); }
  .signin__companion { width: 44px; }
  /* Fit "MM Intelligence" on one line: about 8.8em wide at this stretch. */
  /* "MM INTELLIGENCE" in Termina caps is about 12.6em wide. */
  .signin .wordmark { font-size: calc((100vw - 2 * var(--gutter) - 56px) / 12.6); }
}

.signin__refusal {
  font-size: var(--t-2xl);
  font-stretch: 112%;
  max-width: 24ch;
}

/* Brand graphic elements on sign-in. */
.signin .signin__mm {
  position: absolute;
  left: -2vw;
  bottom: -2vh;
  margin: 0;
  font: 900 clamp(64px, 11vw, 180px) / 0.9 var(--display);
  letter-spacing: 0.02em;
  color: transparent;
  -webkit-text-stroke: 1px rgb(144 177 187 / 0.08);
  white-space: nowrap;
  pointer-events: none;
  user-select: none;
}

.signin__stamp {
  position: absolute;
  right: 4vw;
  bottom: 5vh;
  width: clamp(84px, 9vw, 132px);
  height: auto;
  opacity: 0.35;
  animation: stamp-turn 60s linear infinite;
}
@keyframes stamp-turn { to { transform: rotate(360deg); } }

/* Sign in clicked: the card falls away as we fly into the cluster. */
/* Opacity and transform only: they run on the GPU, so nothing stutters. */
body.warping .signin__card { opacity: 0; transform: scale(0.94); transition: opacity 500ms ease-in, transform 700ms ease-in; }
body.warping .signin__mm, body.warping .signin__stamp { opacity: 0; transition: opacity 400ms ease-in; }
body.warping .signin__cluster { transform: scale(1.6); transition: transform 1s cubic-bezier(0.55, 0, 0.9, 0.4); }

@media (max-width: 640px) {
  .signin__stamp { right: 16px; bottom: auto; top: 16px; width: 64px; }
}

.signin__mark { position: relative; }
.signin__hand {
  position: absolute;
  right: -0.2em;
  bottom: -0.95em;
  font-size: clamp(1.3rem, 0.8rem + 1.6vw, 2.4rem);
  color: var(--solar);
}
@media (max-width: 640px) { .signin__hand { right: 0; bottom: -1.1em; font-size: 1.15rem; } }

.signin .signin__notice {
  margin: 0 0 var(--s-3);
  padding: 8px 14px;
  border-radius: var(--r-pill);
  background: color-mix(in srgb, var(--solar) 16%, transparent);
  color: var(--ink);
  font-size: var(--t-sm);
}