/* Base Reset */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

/* Body Background and Centering */
body {
  font-family: 'Segoe UI', sans-serif;
  background: linear-gradient(to right, #74ebd5, #acb6e5);
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 5vh 2vw;
}

/* Responsive Container */
.container {
  background-color: #fff;
  width: 100%;
  max-width: 500px;
  padding: 2.5rem;
  border-radius: 20px;
  box-shadow: 0 10px 40px rgba(0, 0, 0, 0.15);
  transition: 0.3s ease-in-out;
}

/* Title */
h1 {
  font-size: 1.8rem;
  margin-bottom: 1.5rem;
  color: #2c3e50;
  text-align: center;
}

/* Form Groups */
.form-group {
  margin-bottom: 1.2rem;
}

label {
  font-size: 1rem;
  color: #34495e;
  margin-bottom: 0.5rem;
  display: block;
}

input[type="number"] {
  width: 100%;
  padding: 0.75rem 1rem;
  font-size: 1rem;
  border: 1px solid #ccc;
  border-radius: 10px;
  transition: 0.2s ease;
}

input[type="number"]:focus {
  border-color: #3498db;
  outline: none;
  box-shadow: 0 0 5px rgba(52, 152, 219, 0.2);
}

/* Button */
button {
  width: 100%;
  background-color: #3498db;
  color: #fff;
  font-weight: 600;
  padding: 0.9rem;
  font-size: 1rem;
  border: none;
  border-radius: 10px;
  cursor: pointer;
  transition: background-color 0.3s ease;
  margin-top: 0.5rem;
}

button:hover {
  background-color: #2980b9;
}

/* Result Section */
.output {
  margin-top: 1.8rem;
  padding: 1rem 1.2rem;
  background-color: #f9fafb;
  border-radius: 12px;
  font-size: 1rem;
  color: #2c3e50;
  box-shadow: inset 0 0 10px rgba(0,0,0,0.03);
}

/* RESPONSIVE MEDIA QUERIES */
@media (max-width: 768px) {
  h1 {
    font-size: 1.5rem;
  }

  .container {
    padding: 2rem;
  }

  input, button {
    font-size: 0.95rem;
    padding: 0.65rem 0.9rem;
  }

  .output {
    font-size: 0.95rem;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 1.5rem;
    border-radius: 14px;
  }

  h1 {
    font-size: 1.3rem;
  }

  label, .output, button {
    font-size: 0.9rem;
  }

  input {
    padding: 0.6rem;
  }
}