body{font-family:Arial;background:#f4f6f8}
.card{max-width:600px;margin:50px auto;background:#fff;padding:30px;border-radius:12px}
input,textarea,button{width:100%;margin-top:12px;padding:12px}

button{background:#111;color:#fff;border:0}
.spinner {
  border: 4px solid #f3f3f3;
  border-top: 4px solid #2c3e50;
  border-radius: 50%;
  width: 28px;
  height: 28px;
  animation: spin 1s linear infinite;
  margin: 0 auto 10px;
}

@keyframes spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}