@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@400;600&display=swap');
  * {
    box-sizing: border-box;
  }
  body {
    margin: 0;
    font-family: 'Poppins', sans-serif;
    background: linear-gradient(135deg, #764ba2, #667eea);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    color: #333;
    padding: 20px;
  }
  .container {
    background: #fff;
    width: 450px;
    max-width: 90vw;
    padding: 40px 30px;
    border-radius: 12px;
    box-shadow: 0 15px 30px rgba(0,0,0,0.2);
    animation: fadeInScale 0.6s ease forwards;
  }
  @keyframes fadeInScale {
    0% {
      opacity: 0;
      transform: scale(0.85);
    }
    100% {
      opacity: 1;
      transform: scale(1);
    }
  }
  h2 {
    margin-bottom: 30px;
    font-weight: 600;
    color: #4b3ca7;
    text-align: center;
    letter-spacing: 1.2px;
  }
  form {
    display: flex;
    flex-direction: column;
  }
  label {
    font-weight: 600;
    margin-bottom: 6px;
    color: #5e5e5e;
  }
  input {
    padding: 14px 16px;
    border: 2px solid #ddd;
    border-radius: 8px;
    margin-bottom: 16px;
    font-size: 1rem;
    transition: border-color 0.3s ease;
  }
  input:focus {
    outline: none;
    border-color: #667eea;
    box-shadow: 0 0 8px rgba(102, 126, 234, 0.5);
  }
  input.valid {
    border-color: #27ae60;
  }
  input.invalid {
    border-color: #e74c3c;
  }
  .error-message {
    color: #e74c3c;
    font-size: 0.85rem;
    min-height: 18px;
    margin-top: -12px;
    margin-bottom: 12px;
  }
  .password-strength {
    margin-top: -12px;
    margin-bottom: 12px;
    font-size: 0.85rem;
  }
  .strength-indicator {
    height: 4px;
    border-radius: 2px;
    margin: 8px 0;
    transition: all 0.3s ease;
  }
  .strength-weak { background: #e74c3c; width: 33%; }
  .strength-medium { background: #f39c12; width: 66%; }
  .strength-strong { background: #27ae60; width: 100%; }
  .strength-requirements {
    font-size: 0.8rem;
    color: #666;
    margin-top: 5px;
  }
  .requirement {
    margin: 2px 0;
    transition: color 0.3s ease;
  }
  .requirement.met {
    color: #27ae60;
  }
  button {
    padding: 14px 0;
    background: #667eea;
    color: white;
    font-weight: 700;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-size: 1.1rem;
    letter-spacing: 1px;
    transition: background 0.3s ease;
    margin-top: 10px;
  }
  button:hover:not(:disabled) {
    background: #4a5dca;
  }
  button:disabled {
    background: #ccc;
    cursor: not-allowed;
  }
  .link {
    text-align: center;
    margin-top: 22px;
    font-size: 0.9rem;
    color: #666;
  }
  .link a {
    color: #764ba2;
    font-weight: 600;
    text-decoration: none;
    transition: color 0.3s ease;
  }
  .link a:hover {
    color: #667eea;
  }

  /* Success Popup */
  .popup-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    display: none;
    justify-content: center;
    align-items: center;
    z-index: 1000;
  }
  .popup {
    background: white;
    padding: 40px;
    border-radius: 15px;
    text-align: center;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3);
    animation: popupSlideIn 0.4s ease;
    max-width: 400px;
    margin: 20px;
  }
  @keyframes popupSlideIn {
    0% {
      opacity: 0;
      transform: translateY(-50px) scale(0.8);
    }
    100% {
      opacity: 1;
      transform: translateY(0) scale(1);
    }
  }
  .popup-icon {
    width: 80px;
    height: 80px;
    background: #27ae60;
    border-radius: 50%;
    margin: 0 auto 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 40px;
    color: white;
  }
  .popup h3 {
    color: #27ae60;
    margin: 0 0 15px;
    font-size: 1.5rem;
  }
  .popup p {
    color: #666;
    margin: 0 0 20px;
    line-height: 1.5;
  }
  .countdown {
    font-weight: 600;
    color: #4b3ca7;
    font-size: 1.1rem;
  }

  @media (max-width: 480px) {
    body {
      padding: 10px;
    }
    .container {
      width: 100%;
      padding: 30px 20px;
      border-radius: 8px;
    }
    h2 {
      font-size: 1.6rem;
    }
  }