body {
  font-family: Arial, sans-serif;
  background: #f4f4f4;
  margin: 0;
  transition: 0.3s;
  font-size: 18px;
}

/* Full page layout */
#container {
  width: 100%;
  height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 15px;
  text-align: center;
}

#text {
  width: 70%;
  font-size: 22px;
  line-height: 1.8;
}

textarea {
  width: 70%;
  height: 140px;
  font-size: 20px;
  padding: 12px;
}

button {
  padding: 10px 20px;
  font-size: 18px;
  cursor: pointer;
  margin: 5px;
}

.result {
  font-size: 20px;
  font-weight: bold;
}

/* Top-right dark button */
.theme-btn {
  position: fixed;
  top: 10px;
  right: 10px;
  border-radius: 6px;
}

/* Dark Mode */
.dark {
  background: #121212;
  color: #fff;
}

.dark textarea {
  background: #1e1e1e;
  color: #fff;
}