body {
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  background: linear-gradient(135deg, #667eea, #764ba2);
  height: 100vh;
  margin: 0;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
}

.container {
  background: white;
  border-radius: 20px;
  box-shadow: 0 10px 25px rgba(0,0,0,0.2);
  padding: 40px;
  text-align: center;
  max-width: 400px;
  width: 90%;
  animation: fadeIn 1.2s ease;
}

h1 {
  font-size: 1.8rem;
  margin-bottom: 20px;
  color: #333;
}

input, button {
  padding: 10px;
  margin: 10px 0;
  width: 100%;
  border-radius: 10px;
  border: 1px solid #ccc;
  font-size: 1rem;
  outline: none;
  transition: 0.3s;
}

input:focus {
  border-color: #667eea;
  box-shadow: 0 0 5px #667eea;
}

button {
  background: linear-gradient(135deg, #667eea, #764ba2);
  color: white;
  border: none;
  cursor: pointer;
  font-weight: bold;
  transition: transform 0.2s;
}

button:hover {
  transform: scale(1.05);
}

.result, .strength {
  margin-top: 15px;
  font-size: 1.1rem;
  font-weight: bold;
  color: #764ba2;
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s, transform 0.6s;
}

.result.show, .strength.show {
  opacity: 1;
  transform: translateY(0);
}

footer {
  margin-top: 20px;
  color: white;
  font-size: 0.9rem;
  text-align: center;
  animation: fadeIn 1.5s ease;
}

@keyframes fadeIn {
  from { opacity: 0; transform: scale(0.9); }
  to { opacity: 1; transform: scale(1); }
}