:root {
  --bg-color: #ffffff;
  --text-color: #222222;
  --wall-color: #444444;
  --highlight-start: lightgreen;
  --highlight-end: lightcoral;
  --arrow-color: #00BFFF;
  --font-family: 'Segoe UI', sans-serif;
}

body.dark-mode {
  --bg-color: #121212;
  --text-color: #eeeeee;
  --wall-color: #bbbbbb;
  --highlight-start: #2e8b57;
  --highlight-end: #b22222;
  --arrow-color: #1e90ff;
}

body {
  background-color: var(--bg-color);
  color: var(--text-color);
  font-family: var(--font-family);
  margin: 0;
  padding: 1rem;
  transition: background-color 0.3s ease, color 0.3s ease;
}

canvas {
  display: block;
  margin: 1rem auto;
  background-color: var(--bg-color);
  border: 1px solid var(--wall-color);
  box-shadow: 0 0 10px rgba(0,0,0,0.1);
  transition: background-color 0.3s ease;
}

#triCanvas, #triangleCanvas {
  display: block;
  margin: 1rem auto;
  border: 1px solid var(--wall-color);
  background-color: var(--bg-color);
}


button {
  background-color: var(--wall-color);
  color: var(--bg-color);
  border: none;
  padding: 0.5rem 1rem;
  margin: 0.5rem;
  cursor: pointer;
  font-size: 1rem;
  border-radius: 4px;
  transition: background-color 0.3s ease, color 0.3s ease;
}

button:hover {
  background-color: var(--highlight-start);
  color: var(--text-color);
}

input, select {
  padding: 0.4rem;
  margin: 0.3rem;
  border: 1px solid var(--wall-color);
  border-radius: 4px;
  background-color: var(--bg-color);
  color: var(--text-color);
  transition: background-color 0.3s ease, color 0.3s ease;
}

label {
  margin-right: 0.5rem;
}

.controls {
  text-align: center;
  margin-bottom: 1rem;
}

footer {
  text-align: center;
  font-size: 0.9rem;
  margin-top: 2rem;
  color: var(--wall-color);
}