:root {
  color-scheme: light;
  --bg-top: #77c6ff;
  --bg-bottom: #e7f8ff;
  --panel: #ffffffcc;
  --text: #0d2740;
  --accent: #2f8f2f;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  display: grid;
  place-items: center;
  font-family: "Trebuchet MS", "Segoe UI", sans-serif;
  background: linear-gradient(180deg, var(--bg-top), var(--bg-bottom));
  color: var(--text);
}

.container {
  width: min(96vw, 560px);
  padding: 16px;
  border-radius: 16px;
  background: var(--panel);
  box-shadow: 0 12px 28px #00000022;
  text-align: center;
}

h1 {
  margin: 6px 0 12px;
  letter-spacing: 0.5px;
}

canvas {
  width: 100%;
  max-width: 480px;
  height: auto;
  border: 3px solid #ffffff;
  border-radius: 10px;
  background: linear-gradient(180deg, #70c2ff 0%, #8fe1ff 55%, #c8f5ff 100%);
  display: block;
  margin: 0 auto;
}

.controls {
  margin: 12px 0 6px;
  font-size: 0.95rem;
}

kbd {
  padding: 2px 6px;
  border-radius: 6px;
  border: 1px solid #00000030;
  background: #ffffff;
  font-weight: 700;
}