* {
  box-sizing: border-box;
}

body {
  font-family: 'Segoe UI', sans-serif;
  margin: 0;
  padding: 0;
  background-color: #f4f4f4;
  color: #333;
  transition: background-color 0.4s, color 0.4s;
}

.container {
  max-width: 500px;
  margin: 60px auto;
  padding: 30px;
  background: #ffffff;
  border-radius: 15px;
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.1);
  transition: background-color 0.4s, color 0.4s;
}

h2 {
  text-align: center;
  margin-bottom: 20px;
}

input,
select,
button {
  width: 100%;
  padding: 12px;
  margin: 12px 0;
  font-size: 16px;
  border-radius: 8px;
  border: 1px solid #ccc;
}

button {
  background-color: #007bff;
  color: white;
  border: none;
  cursor: pointer;
  transition: background-color 0.3s;
}

button:hover {
  background-color: #0056b3;
}

.result {
  background: #f3f3f3;
  padding: 15px;
  border-radius: 10px;
  margin-top: 15px;
  font-size: 15px;
}

/* Dark Mode */
.dark-mode {
  background-color: #111;
  color: #eee;
}

.dark-mode .container {
  background-color: #1e1e1e;
  color: #eee;
  box-shadow: 0 0 15px rgba(255, 255, 255, 0.05);
}

.dark-mode input,
.dark-mode select {
  background-color: #333;
  color: #eee;
  border: 1px solid #555;
}

.dark-mode button {
  background-color: #ffc107;
  color: #000;
}

.dark-mode .result {
  background-color: #222;
  border: 1px solid #333;
}

/* Compact Dark Mode Toggle Button */
.toggle-theme {
  position: fixed;
  top: 10px;
  right: 10px;
  font-size: 18px;
  padding: 5px 10px;
  background-color: #eee;
  color: #333;
  border: 1px solid #ccc;
  border-radius: 50%;
  cursor: pointer;
  z-index: 999;
  transition: all 0.3s ease;
}

.dark-mode .toggle-theme {
  background-color: #222;
  color: #fff;
  border: 1px solid #555;
}

/* Responsive */
@media (max-width: 600px) {
  .container {
    margin: 30px 15px;
    padding: 20px;
  }

  input,
  select,
  button {
    font-size: 15px;
    padding: 10px;
  }

  .toggle-theme {
    font-size: 16px;
    padding: 4px 8px;
    top: 8px;
    right: 8px;
  }

  h2 {
    font-size: 20px;
  }

  .result {
    font-size: 14px;
  }
}