* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: 'Segoe UI', Arial, sans-serif;
  background: radial-gradient(circle at 50% 50%, #222, #000 80%);
  color: #fff;
  min-height: 100vh;
  overflow-x: hidden;
  padding: 0 1rem;
  display: flex;
  align-items: center;
  justify-content: center;
  animation: pulseBg 10s infinite alternate;
}

@keyframes pulseBg {
  0% { filter: brightness(1); }
  50% { filter: brightness(1.2); }
  100% { filter: brightness(1); }
}

main {
  text-align: center;
}

.title {
  font-size: 3rem;
  margin-bottom: 1rem;
  letter-spacing: 0.05em;
  font-weight: 700;
  text-shadow: 0 0 10px rgba(255, 255, 255, 0.4);
}

.btn {
  background: transparent;
  color: #fff;
  border: 2px solid #fff;
  border-radius: 4px;
  padding: 0.75rem 1.5rem;
  font-size: 1rem;
  cursor: pointer;
  transition: box-shadow 0.3s, transform 0.3s;
}

.btn:hover,
.btn:focus {
  box-shadow: 0 0 10px #fff;
  transform: scale(1.05);
}


@media (max-width: 600px) {
  .title {
    font-size: 2rem;
  }
}