body {
  margin: 0;
  font-family: Arial, sans-serif;
  background: #f5f5f5;
}

.page {
  display: flex;
  justify-content: center;
  padding: 40px 20px;
}

.container {
  display: flex;
  gap: 30px;
  background: #ffffff;
  border: 1px solid #ccc;
  padding: 30px;
  width: 900px;
  box-sizing: border-box;
}

.left-panel {
  width: 300px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.right-panel {
  flex: 1;
  display: flex;
  flex-direction: column;
}

input,
textarea,
button {
  font-size: 14px;
  padding: 10px;
  box-sizing: border-box;
}

textarea {
  resize: vertical;
}

#messageText {
  min-height: 80px;
}

#response {
  width: 100%;
  height: 420px;
  margin-top: 8px;
  font-family: Consolas, monospace;
}

button {
  cursor: pointer;
  background: #f0f0f0;
  border: 1px solid #bbb;
}

button:hover {
  background: #e6e6e6;
}