body {
  font-family: system-ui, sans-serif;
  background: #f4f7f5;
  margin: 0;
  padding: 0;
  color: #222;
}

.container {
  max-width: 700px;
  margin: 3rem auto;
  background: white;
  padding: 2rem;
  border-radius: 1rem;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

h1 {
  text-align: center;
  color: #1b4332;
  margin-bottom: 1rem;
}

form {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

label {
  font-weight: 600;
}

input {
  padding: 0.5rem;
  border-radius: 6px;
  border: 1px solid #ccc;
  font-size: 1rem;
}

#result {
  margin-top: 1.5rem;
  text-align: center;
}

.output {
  font-size: 1.2rem;
  color: #081c15;
}

.error {
  color: #d00000;
  font-weight: bold;
}

#forestViz {
  width: 100%;
  margin-top: 2rem;
  border: 1px solid #ccc;
  background: #e9f5ec;
  border-radius: 8px;
  transition: all 0.3s ease;
}

option {
  padding: 0.5rem;
  border-radius: 6px;
  border: 1px solid #ccc;
  font-size: 0.85rem;
}

footer {
  text-align: center;
  font-size: 0.85rem;
  margin-top: 2rem;
  color: #555;
}

ref {
  text-align: center;
  font-size: 0.65rem;
  margin-top: 2rem;
  color: #555;
}

a:link {
  text-align: center;#
  text-decoration: underline;
  margin-top: 2rem;
  color: #555;
}