* {
  box-sizing: border-box;
}

html, body {
  height: 100%;
  margin: 0;
  padding: 0;
}

.container {
  max-width: 800px;
  margin: 0 auto;
  padding: 20px;
}

h1 {
  text-align: center;
}

form {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-bottom: 20px;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 5px;
}

label {
  font-weight: bold;
}

textarea {
  padding: 10px;
  border: 1px solid #ccc;
  border-radius: 5px;
  font-size: 16px;
  font-family: 'Courier New', Courier, monospace;
}

button {
  padding: 10px;
  background-color: #4CAF50;
  color: #fff;
  border: none;
  border-radius: 5px;
  font-size: 16px;
  cursor: pointer;
}

#diff-result {
  border: 1px solid #ccc;
  border-radius: 5px;
  padding: 10px;
  margin-top: 20px;
  font-family: 'Courier New', Courier, monospace;
  height: 500px;
  overflow: scroll;
}

.added {
  background-color: #d6fdd6;
}

.removed {
  background-color: #ffd6d6;
}