body {
  background: #111;
  color: #eee;
  font-family: "Segoe UI", sans-serif;
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  margin: 0;
}

.container {
  background: #222;
  padding: 25px;
  border-radius: 12px;
  width: 400px;
  text-align: center;
  box-shadow: 0 0 20px rgba(84, 125, 221, 0.7);
}

h1 {
  margin-bottom: 15px;
}

input {
  width: 100%;
  padding: 12px;
  border: none;
  border-radius: 8px;
  font-size: 1rem;
  margin-bottom: 15px;
  outline: none;
}

.strength {
  width: 100%;
  height: 10px;
  background: #333;
  border-radius: 5px;
  margin-bottom: 10px;
  overflow: hidden;
}

#strength-bar {
  height: 100%;
  width: 0%;
  background: red;
  transition: width 0.3s ease, background 0.3s ease;
}

#strength-text {
  margin: 10px 0;
  font-weight: bold;
}

#requirements {
  list-style: none;
  padding: 0;
  text-align: left;
  font-size: 0.9rem;
}

#requirements li {
  margin: 5px 0;
  transition: color 0.2s;
}

.valid {
  color: #4caf50;
}
.invalid {
  color: #ff4747;
}