* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Segoe UI", Tahoma, sans-serif;
  background: linear-gradient(135deg, #eef2ff, #f8fafc);
  color: #0f172a;
}

.container {
  max-width: 1080px;
  margin: 0 auto;
  padding: 24px;
}

h1 {
  margin: 0 0 8px;
  font-size: 1.6rem;
}

.hint {
  margin: 0 0 18px;
  color: #334155;
}

.panel {
  background: #ffffff;
  border: 1px solid #dbe4ff;
  border-radius: 12px;
  padding: 16px;
  margin-bottom: 18px;
}

.row {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 12px;
}

button {
  border: 1px solid #2563eb;
  background: #2563eb;
  color: #fff;
  border-radius: 10px;
  padding: 10px 14px;
  cursor: pointer;
  margin-right: 8px;
}

button:disabled {
  opacity: 0.55;
  cursor: not-allowed;
}

#log {
  margin-top: 12px;
  padding: 10px;
  background: #0b1021;
  color: #d1e4ff;
  border-radius: 8px;
  min-height: 72px;
  white-space: pre-wrap;
}

.grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

figure {
  margin: 0;
  background: #fff;
  border: 1px solid #dbe4ff;
  border-radius: 12px;
  padding: 12px;
}

figcaption {
  margin-bottom: 8px;
  color: #334155;
}

canvas {
  width: 100%;
  max-height: 70vh;
  background:
    linear-gradient(45deg, #eef2ff 25%, transparent 25%),
    linear-gradient(-45deg, #eef2ff 25%, transparent 25%),
    linear-gradient(45deg, transparent 75%, #eef2ff 75%),
    linear-gradient(-45deg, transparent 75%, #eef2ff 75%);
  background-size: 16px 16px;
  background-position: 0 0, 0 8px, 8px -8px, -8px 0;
  border-radius: 8px;
}

@media (max-width: 900px) {
  .grid {
    grid-template-columns: 1fr;
  }
}