* { box-sizing: border-box; margin: 0; padding: 0; }
body { font-family: system-ui, sans-serif; max-width: 480px; margin: 40px auto; padding: 0 16px; }
h1 { margin-bottom: 24px; }
label { display: block; font-weight: 600; margin-bottom: 4px; }
input[type="text"], input[type="file"], input[type="number"], select {
  width: 100%; padding: 8px; margin-bottom: 16px; border: 1px solid #ccc; border-radius: 4px;
}
button { padding: 10px 20px; background: #111; color: #fff; border: none; cursor: pointer; border-radius: 4px; }
button:disabled { opacity: 0.5; }
.file-row { display: flex; align-items: center; gap: 8px; margin-bottom: 16px; }
.file-row input[type="file"] { margin-bottom: 0; }
.clear-btn { padding: 6px 12px; background: #888; font-size: 0.85rem; }
#result { margin-top: 24px; text-align: center; }
#result img { max-width: 100%; border: 1px solid #ddd; }
.qr-info { margin-top: 8px; font-size: 0.9rem; color: #555; }

/* Tabs */
.tabs { display: flex; gap: 0; margin-bottom: 24px; border-bottom: 2px solid #ddd; }
.tab-btn {
  padding: 10px 20px; background: none; color: #555; border: none;
  cursor: pointer; font-size: 1rem; font-weight: 600;
  border-bottom: 2px solid transparent; margin-bottom: -2px;
}
.tab-btn.active { color: #111; border-bottom-color: #111; }
.tab-panel { display: none; }
.tab-panel.active { display: block; }