/* ===== FLASH MATH ===== */
.fm-stage {
  width: 100%;
  max-width: 400px;
  height: 200px;
  background: var(--card);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--card-border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  position: relative;
}
.fm-number {
  font-size: 6.5rem;
  font-weight: 800;
  color: #fff;
  text-shadow: 0 4px 20px rgba(139, 92, 246, 0.9);
  opacity: 0;
  transform: scale(0.6);
  transition: opacity 0.1s ease-out, transform 0.15s cubic-bezier(0.175,0.885,0.32,1.275);
}
.fm-number.show {
  opacity: 1;
  transform: scale(1);
}
.fm-visual {
  position: absolute;
  inset: 0;
  opacity: 0;
  transform: scale(0.6);
  transition: opacity 0.1s ease-out, transform 0.15s cubic-bezier(0.175,0.885,0.32,1.275);
}
.fm-visual.show {
  opacity: 1;
  transform: scale(1);
}
.fm-message {
  position: absolute;
  top: 16px;
  color: #fff;
  font-size: 1rem;
  font-weight: 800;
  letter-spacing: 1px;
}
.fm-numpad {
  max-width: 400px;
}