body {
  margin: 0;
  font-family: sans-serif;
  background: #f0f0f0;
}

header {
  height: 80px;
  background: #222;
  color: white;
  display: flex;
  align-items: center;
  padding-left: 20px;
}

/* main */
#wrapper {
  display: flex;
  flex-direction: column;
  align-items: center;
  margin-top: 40px;
  gap: 20px;
}

.upload-btn {
  padding: 10px 20px;
  background: #333;
  color: white;
  cursor: pointer;
  z-index: 10;
}

.upload-btn:hover {
  background: #555;
}

/* canvas */
#stageContainer {
  width: 800px;
  height: 500px;
  background: white;
  border: 2px dashed #999;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  z-index: 0;
}

.hint {
  text-align: center;
  color: #777;
}

.hint small {
  font-size: 12px;
  color: #aaa;
  /* I chose this color to make it different from main text */
}