#validation-input {
  border: 3px solid #bdbdbd;
}

#validation-input.valid {
  border-color: #4caf50;
}

#validation-input.invalid {
  border-color: #f44336;
}

body {
  font-family: Arial, sans-serif;
  margin: 20px;
  transition: background-color 0.3s ease;
}

section {
  margin-bottom: 30px;
  padding: 20px;
  border: 1px solid #ddd;
  border-radius: 5px;
}

h2 {
  margin-top: 0;
  color: #333;
}

label {
  margin-right: 15px;
  cursor: pointer;
}

input[type="text"] {
  padding: 8px;
  font-size: 16px;
  margin: 5px 0;
}

input[type="range"] {
  width: 200px;
  margin: 10px 0;
}

#text {
  display: inline-block;
  margin-top: 10px;
  font-weight: bold;
}