/* Écran de bienvenue — noir total, centré, apparitions séquencées. */
.welcome-screen {
  position: fixed;
  inset: 0;
  background: #000;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}
.welcome-screen::before {
  content: '';
  position: absolute;
  width: 600px; height: 600px;
  background: radial-gradient(circle, rgba(34,197,94,0.10), transparent 70%);
  filter: blur(40px);
  animation: pulseGlow 5s ease-in-out infinite;
}
@keyframes pulseGlow {
  0%, 100% { opacity: 0.5; transform: scale(1); }
  50% { opacity: 0.9; transform: scale(1.08); }
}

.welcome-center { text-align: center; position: relative; z-index: 2; }

.brand-small {
  display: block;
  color: var(--accent);
  font-size: 1rem;
  letter-spacing: 6px;
  font-weight: 300;
  text-transform: lowercase;
  margin-bottom: -6px;
}
.brand-big {
  font-size: 6.5rem;
  font-weight: 200;
  letter-spacing: -3px;
  color: var(--text-primary);
  line-height: 1;
}

.greeting {
  margin-top: 26px;
  font-size: 1.3rem;
  color: var(--text-secondary);
  font-weight: 300;
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 0.8s ease, transform 0.8s ease;
}
.greeting.show { opacity: 1; transform: none; }

.start-btn {
  margin-top: 38px;
  font-size: 1.05rem;
  padding: 14px 40px;
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 0.8s ease, transform 0.8s ease, background 0.2s ease;
}
.start-btn.show { opacity: 1; transform: none; }