* {
  box-sizing: border-box;
}

body {
  font-family: Arial, sans-serif;
  background: #f7f7f7;
  color: #333;
  margin: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
}

.container {
  background: #fff;
  padding: 25px;
  border-radius: 12px;
  box-shadow: 0 6px 16px rgba(0,0,0,0.1);
  max-width: 600px;
  width: 90%;
  text-align: center;
}

h1 {
  margin-bottom: 20px;
}

.upload-section {
  margin-bottom: 20px;
}

.upload-label {
  display: inline-block;
  padding: 10px 18px;
  background: #007bff;
  color: #fff;
  border-radius: 6px;
  cursor: pointer;
  font-weight: bold;
  margin-bottom: 8px;
}

.upload-label:hover {
  background: #0056b3;
}

#imageUpload {
  display: none;
}

.hint {
  font-size: 14px;
  color: #666;
}

.canvas-wrapper {
  margin: 15px 0;
}

canvas {
  max-width: 100%;
  border: 1px solid #ddd;
  border-radius: 6px;
}

.controls {
  margin: 15px 0;
  text-align: left;
}

.controls label {
  display: block;
  margin: 8px 0 4px;
  font-weight: bold;
}

input[type="range"] {
  width: 100%;
}

button {
  padding: 10px 20px;
  margin: 10px 5px;
  border: none;
  border-radius: 6px;
  font-weight: bold;
  cursor: pointer;
}

#resetBtn {
  background: #f0f0f0;
  color: #333;
}

#resetBtn:hover {
  background: #e0e0e0;
}

#downloadBtn {
  background: #28a745;
  color: #fff;
}

#downloadBtn:disabled {
  background: #bbb;
  cursor: not-allowed;
}

#downloadBtn:hover:not(:disabled) {
  background: #1f7a33;
}