body {
  font-family: Arial, sans-serif;
  margin: 0;
  padding: 0;
  background-color: #1a1a1a;
  color: #fff;
  transition: background-color 0.3s, color 0.3s;
}
body.light-theme {
  background-color: #fff;
  color: #000;
}
.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 20px 10px;
}
.main-flex {
  display: flex;
  align-items: flex-start;
  justify-content: center;
  gap: 32px;
}
.left-panel {
  flex: 1 1 350px;
  min-width: 260px;
  max-width: 420px;
}
.right-panel {
  flex: 1 1 400px;
  min-width: 260px;
  max-width: 500px;
  display: flex;
  flex-direction: column;
  align-items: center;
}
h1 {
  font-size: 2rem;
  margin-bottom: 10px;
}
#question {
  font-size: 1.3rem;
  margin-bottom: 18px;
  min-height: 2.5em;
  text-align: left;
}
#stats {
  font-size: 1.1rem;
  margin-bottom: 10px;
  text-align: left;
}
button, input[type="text"], input[type="number"] {
  width: 100%;
  max-width: 340px;
  margin: 6px 0;
  font-size: 1rem;
  border-radius: 5px;
  border: none;
  padding: 10px;
  box-sizing: border-box;
}
button {
  background-color: #45a049;
  color: #fff;
  cursor: pointer;
  border: none;
  margin-bottom: 4px;
  transition: background 0.2s, color 0.2s;
}
button#toggleTheme {
  background-color: #f57c00;
  margin-bottom: 16px;
  position: fixed;
  top: 18px;
  right: 18px;
  z-index: 1000;
  width: auto;
  min-width: 120px;
  max-width: 200px;
  padding: 10px 18px;
}
button:disabled, button[disabled] {
  background-color: #bbb !important;
  color: #666 !important;
  cursor: not-allowed;
}
body.light-theme button {
  background-color: #4CAF50;
  color: #fff;
}
body.light-theme button#toggleTheme {
  background-color: #ff9800;
}
input[type="text"], input[type="number"] {
  background-color: #333;
  color: #fff;
  border: 1px solid #555;
}
body.light-theme input[type="text"], body.light-theme input[type="number"] {
  background-color: #fff;
  color: #000;
  border-color: #ccc;
}
#feedback {
  font-weight: bold;
  margin-top: 10px;
  min-height: 2em;
}
#sketch-holder {
  width: 100%;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 350px;
}
canvas {
  border: 1px solid #fff;
  background: #e0e0e0;
  max-width: 100%;
  height: auto;
}
body.light-theme canvas {
  border-color: #000;
}
@media (max-width: 900px) {
  .main-flex {
    flex-direction: column;
    gap: 0;
  }
  .left-panel, .right-panel {
    max-width: 100%;
    min-width: 0;
  }
  #sketch-holder {
    min-height: 260px;
  }
  button#toggleTheme {
    position: static;
    width: 100%;
    min-width: unset;
    max-width: unset;
    margin-bottom: 16px;
    top: unset;
    right: unset;
  }
}
@media (max-width: 600px) {
  .container {
    padding: 8px 2px;
  }
  h1 {
    font-size: 1.2rem;
  }
  #question {
    font-size: 1rem;
  }
  #stats {
    font-size: 0.95rem;
  }
}