* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
}

.container {
  background: white;
  border-radius: 20px;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
  padding: 40px;
  width: 100%;
  max-width: 500px;
  text-align: center;
}

.logo {
  margin-bottom: 30px;
}

.logo i {
  font-size: 48px;
  color: #667eea;
  margin-bottom: 10px;
}

h1 {
  color: #333;
  margin-bottom: 10px;
  font-size: 28px;
}

.subtitle {
  color: #666;
  margin-bottom: 30px;
  font-size: 16px;
}

.input-group {
  margin-bottom: 25px;
}

input[type="text"] {
  width: 100%;
  padding: 15px 20px;
  border: 2px solid #e0e0e0;
  border-radius: 10px;
  font-size: 16px;
  transition: all 0.3s ease;
  outline: none;
}

input[type="text"]:focus {
  border-color: #667eea;
  box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.generate-btn {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  border: none;
  padding: 15px 30px;
  border-radius: 10px;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  width: 100%;
  margin-bottom: 25px;
}

.generate-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 20px rgba(102, 126, 234, 0.3);
}

.generate-btn:active {
  transform: translateY(0);
}

.qr-container {
  margin: 25px 0;
  display: flex;
  justify-content: center;
  min-height: 256px;
}

#qrCode {
  border: 10px solid white;
  border-radius: 15px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

.download-btn {
  background: #4CAF50;
  color: white;
  border: none;
  padding: 12px 25px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.download-btn:hover {
  background: #45a049;
  transform: translateY(-1px);
}

.error {
  color: #e74c3c;
  margin-top: 10px;
  font-size: 14px;
  display: none;
}

.features {
  margin-top: 30px;
  text-align: left;
}

.features h3 {
  color: #333;
  margin-bottom: 15px;
}

.features ul {
  list-style: none;
}

.features li {
  padding: 8px 0;
  color: #666;
  display: flex;
  align-items: center;
  gap: 10px;
}

.features i {
  color: #667eea;
}

@media (max-width: 600px) {
  .container {
    padding: 30px 20px;
  }
  
  h1 {
    font-size: 24px;
  }
  
  input[type="text"] {
    padding: 12px 15px;
  }
  
  .generate-btn {
    padding: 12px 20px;
  }
}