* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background-color: #111827;
  color: white;
}

.max-w-2xl {
  max-width: 42rem;
  margin-left: auto;
  margin-right: auto;
}

.p-6 {
  padding: 1.5rem;
}

.text-center {
  text-align: center;
}

.mb-2 {
  margin-bottom: 0.5rem;
}

.mb-4 {
  margin-bottom: 1rem;
}

.mb-8 {
  margin-bottom: 2rem;
}

.mt-2 {
  margin-top: 0.5rem;
}

.mt-4 {
  margin-top: 1rem;
}

.mt-6 {
  margin-top: 1.5rem;
}

.text-3xl {
  font-size: 1.875rem;
  font-weight: bold;
}

.text-xl {
  font-size: 1.25rem;
  font-weight: 600;
}

.text-4xl {
  font-size: 2.25rem;
  font-weight: bold;
}

.text-sm {
  font-size: 0.875rem;
}

.font-semibold {
  font-weight: 600;
}

.font-bold {
  font-weight: bold;
}

.font-mono {
  font-family: monospace;
}

.text-gray-400 {
  color: #9ca3af;
}

.text-gray-900 {
  color: #111827;
}

.text-white {
  color: white;
}

.text-red-400 {
  color: #f87171;
}

.text-green-400 {
  color: #4ade80;
}

.text-blue-400 {
  color: #60a5fa;
}

.bg-gray-800 {
  background-color: #1f2937;
}

.bg-gray-700 {
  background-color: #374151;
}

.bg-gray-900 {
  background-color: #111827;
}

.bg-blue-600 {
  background-color: #2563eb;
}

.bg-green-600 {
  background-color: #16a34a;
}

.rounded-2xl {
  border-radius: 1rem;
}

.rounded-lg {
  border-radius: 0.5rem;
}

.shadow-xl {
  box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
}

.space-y-2 > * + * {
  margin-top: 0.5rem;
}

.space-y-4 > * + * {
  margin-top: 1rem;
}

.w-full {
  width: 100%;
}

.inline-block {
  display: inline-block;
}

.hidden {
  display: none;
}

.border {
  border: 1px solid;
}

.border-gray-600 {
  border-color: #4b5563;
}

.px-4 {
  padding-left: 1rem;
  padding-right: 1rem;
}

.py-3 {
  padding-top: 0.75rem;
  padding-bottom: 0.75rem;
}

.py-2 {
  padding-top: 0.5rem;
  padding-bottom: 0.5rem;
}

.py-4 {
  padding-top: 1rem;
  padding-bottom: 1rem;
}

.transition-colors {
  transition-property: color, background-color, border-color, text-decoration-color, fill, stroke;
}

.hover\:bg-blue-700:hover {
  background-color: #1d4ed8;
}

.hover\:bg-green-700:hover {
  background-color: #15803d;
}

.focus\:outline-none:focus {
  outline: none;
}

.focus\:ring-2:focus {
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.5);
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.5; }
}

.animate-pulse {
  animation: pulse 2s cubic-bezier(0.4, 0, 0.6, 1) infinite;
}

.qr-container canvas {
  border-radius: 12px;
  box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

button:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

input {
  color: white;
}

input::placeholder {
  color: #9ca3af;
}