* {
  box-sizing: border-box;
}

/* How to use section */
.how-to-use {
  margin-bottom: 16px;
  background: #f8f9fa;
  border: 1px solid #e9ecef;
  border-radius: 8px;
  padding: 10px 14px;
  font-size: 13px;
  color: #495057;
}

.how-to-use summary {
  cursor: pointer;
  font-weight: 500;
  color: #185fa5;
}

.how-to-use-content {
  margin-top: 8px;
  line-height: 1.5;
  color: #6c757d;
}

/* Notice box */
.notice-box {
  background: #fff8e6;
  border: 1px solid #ffe8a1;
  border-radius: 8px;
  padding: 10px 14px;
  font-size: 13px;
  color: #856404;
  margin-bottom: 20px;
}

/* Drop zone */
.drop-zone {
  border: 2px dashed #ccc;
  border-radius: 12px;
  padding: 24px 16px;
  text-align: center;
  cursor: pointer;
  color: #888;
  transition: border-color 0.2s ease, background 0.2s ease;
}

.drop-zone:hover,
.drop-zone.dragover {
  border-color: #185fa5;
  background: #f0f6fc;
}

/* Grid Layout */
.qr-grid {
  display: grid;
  grid-template-columns: 340px 1fr;
  gap: 24px;
  align-items: start;
  width: 100%;
  margin-top: 20px;
}

@media (max-width: 768px) {
  .qr-grid {
    grid-template-columns: 1fr;
  }
}

/* Controls */
.control-panel {
  display: flex;
  flex-direction: column;
  gap: 14px;
  width: 100%;
}

.field-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
  width: 100%;
}

.field-label {
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-size: 13px;
  color: #555;
  width: 100%;
}

.field-label input[type="text"],
.field-group select {
  width: 100%;
  padding: 9px 12px;
  border: 1px solid #ddd;
  border-radius: 8px;
  font-size: 14px;
  box-sizing: border-box;
}

.color-inputs {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  width: 100%;
}

.color-inputs input[type="color"] {
  width: 100%;
  height: 38px;
  border: 1px solid #ddd;
  border-radius: 8px;
  cursor: pointer;
  background: white;
  padding: 2px;
}

/* Action Buttons */
.action-row {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  margin-top: 10px;
}

.action-row button {
  padding: 9px 18px;
  background: white;
  color: #185fa5;
  border: 1px solid #185fa5;
  border-radius: 8px;
  font-size: 13px;
  cursor: pointer;
}

.action-row button:hover {
  background: #f0f6fc;
}

/* Preview Panel */
.preview-panel {
  display: flex;
  flex-direction: column;
  gap: 8px;
  width: 100%;
  min-width: 0;
}

.preview-title {
  font-size: 13px;
  color: #666;
}

.img-preview-container {
  border: 1px solid #ddd;
  border-radius: 8px;
  padding: 16px;
  background: #f9f9f9;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 250px;
  max-height: 480px;
  overflow: hidden;
  box-sizing: border-box;
}

.img-preview-container img {
  max-width: 100%;
  max-height: 380px;
  object-fit: contain;
  border-radius: 4px;
  display: block;
}

/* Status Messages */
.status-msg {
  font-size: 13px;
  color: #666;
}

.status-msg.error {
  color: #a71a1a;
}

.status-msg.success {
  color: #1a7a3c;
}