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

body {
  background: #f3f4f6;
  font-family: Arial, sans-serif;
  min-height: 100vh;
  padding: 32px 20px 48px;
}

.page {
  width: 100%;
  max-width: 920px;
  margin: 0 auto;
}

.container {
  background: white;
  width: 100%;
  max-width: 500px;
  padding: 30px;
  border-radius: 20px;
  box-shadow: 0 10px 30px rgba(0,0,0,0.1);
  margin: 0 auto;
}

h1 {
  text-align: center;
  margin-bottom: 16px;
  color: #111827;
}

.subtitle {
  text-align: center;
  color: #4b5563;
  line-height: 1.6;
  margin-bottom: 24px;
}

.form-group {
  margin-bottom: 20px;
}

label {
  display: block;
  margin-bottom: 10px;
  color: #374151;
  font-weight: bold;
}

input[type="text"],
input[type="file"] {
  width: 100%;
  padding: 12px;
  border: 1px solid #d1d5db;
  border-radius: 10px;
}

button {
  width: 100%;
  padding: 14px;
  background: black;
  color: white;
  border: none;
  border-radius: 10px;
  font-size: 16px;
  cursor: pointer;
  margin-top: 10px;
}

button:hover {
  opacity: 0.9;
}

.helper-text {
  margin-top: 12px;
  text-align: center;
  color: #6b7280;
  font-size: 13px;
  line-height: 1.7;
}

.qr-container {
  margin-top: 30px;
  text-align: center;
}

canvas {
  max-width: 100%;
}

#downloadBtn {
  display: none;
  background: #16a34a;
}

.info-box {
  margin-top: 24px;
  text-align: center;
  font-size: 13px;
  color: #6b7280;
  line-height: 1.9;
  border-top: 1px solid #e5e7eb;
  padding-top: 16px;
}

.info-box .credit {
  color: #374151;
  font-size: 12.5px;
}

@media (max-width: 640px) {
  body {
    padding: 20px 14px 36px;
  }

  .container {
    padding: 22px;
  }
}