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

    body {
      font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
      background: linear-gradient(135deg, #1e3c72 0%, #2a5298 25%, #667eea 50%, #764ba2 75%, #f093fb 100%);
      min-height: 100vh;
      padding: 20px;
      position: relative;
      overflow-x: hidden;
    }

    /* Animated background elements */
    body::before {
      content: '';
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background: 
        radial-gradient(circle at 20% 80%, rgba(120, 119, 198, 0.3) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(255, 119, 198, 0.3) 0%, transparent 50%),
        radial-gradient(circle at 40% 40%, rgba(120, 219, 255, 0.2) 0%, transparent 50%);
      animation: backgroundShift 15s ease-in-out infinite;
    }

    @keyframes backgroundShift {
      0%, 100% { opacity: 1; transform: scale(1) rotate(0deg); }
      50% { opacity: 0.8; transform: scale(1.1) rotate(2deg); }
    }

    .container {
      max-width: 500px;
      margin: 0 auto;
      position: relative;
      z-index: 1;
    }

    .heading {
      text-align: center;
      color: white;
      font-size: 2.8rem;
      font-weight: 800;
      margin-bottom: 40px;
      text-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
      background: linear-gradient(135deg, #fff 0%, #f8f9ff 50%, #e6f3ff 100%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      animation: titleGlow 3s ease-in-out infinite alternate;
      line-height: 1.2;
    }

    @keyframes titleGlow {
      from { filter: drop-shadow(0 0 10px rgba(255, 255, 255, 0.3)); }
      to { filter: drop-shadow(0 0 20px rgba(255, 255, 255, 0.6)); }
    }

    .registration-card {
      background: rgba(255, 255, 255, 0.1);
      backdrop-filter: blur(25px);
      border: 1px solid rgba(255, 255, 255, 0.2);
      border-radius: 28px;
      padding: 50px 40px;
      box-shadow: 
        0 30px 60px rgba(0, 0, 0, 0.15),
        inset 0 1px 0 rgba(255, 255, 255, 0.2);
      position: relative;
      animation: cardSlideUp 1s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    }

    @keyframes cardSlideUp {
      from {
        opacity: 0;
        transform: translateY(60px) scale(0.9);
      }
      to {
        opacity: 1;
        transform: translateY(0) scale(1);
      }
    }

    .form-group {
      margin-bottom: 28px;
      position: relative;
    }

    .form-group label {
      display: block;
      color: rgba(255, 255, 255, 0.9);
      font-size: 1.1rem;
      font-weight: 600;
      margin-bottom: 8px;
      text-shadow: 0 1px 3px rgba(0, 0, 0, 0.2);
    }

    .form-group input {
      width: 100%;
      padding: 18px 24px;
      border: 2px solid rgba(255, 255, 255, 0.2);
      border-radius: 16px;
      font-size: 1.1rem;
      background: rgba(255, 255, 255, 0.1);
      color: white;
      transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
      backdrop-filter: blur(10px);
    }

    .form-group input::placeholder {
      color: rgba(255, 255, 255, 0.5);
      font-weight: 400;
    }

    .form-group input:focus {
      outline: none;
      border-color: rgba(255, 255, 255, 0.6);
      background: rgba(255, 255, 255, 0.15);
      transform: translateY(-2px);
      box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    }

    .form-group input:valid {
      border-color: rgba(72, 187, 120, 0.8);
    }

    .form-group input:invalid:not(:placeholder-shown) {
      border-color: rgba(245, 101, 101, 0.8);
    }

    /* Password strength indicator */
    .password-strength {
      height: 4px;
      background: rgba(255, 255, 255, 0.2);
      border-radius: 2px;
      margin-top: 8px;
      overflow: hidden;
    }

    .password-strength-bar {
      height: 100%;
      width: 0%;
      transition: all 0.3s ease;
      border-radius: 2px;
    }

    .strength-weak { background: #ef4444; width: 33%; }
    .strength-medium { background: #f59e0b; width: 66%; }
    .strength-strong { background: #10b981; width: 100%; }

    .password-match {
      font-size: 0.9rem;
      margin-top: 5px;
      transition: all 0.3s ease;
    }

    .match-success { color: #10b981; }
    .match-error { color: #ef4444; }

    .button-container {
      margin-top: 40px;
      text-align: center;
    }

    .register-btn {
      width: 100%;
      padding: 20px;
      background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
      color: white;
      border: none;
      border-radius: 16px;
      font-size: 1.2rem;
      font-weight: 700;
      cursor: pointer;
      transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
      position: relative;
      overflow: hidden;
      text-transform: uppercase;
      letter-spacing: 1px;
      margin-bottom: 25px;
    }

    .register-btn::before {
      content: '';
      position: absolute;
      top: 0;
      left: -100%;
      width: 100%;
      height: 100%;
      background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
      transition: left 0.6s;
    }

    .register-btn:hover {
      transform: translateY(-3px);
      box-shadow: 0 20px 40px rgba(102, 126, 234, 0.4);
    }

    .register-btn:hover::before {
      left: 100%;
    }

    .register-btn:active {
      transform: translateY(-1px);
    }

    .register-btn:disabled {
      opacity: 0.6;
      cursor: not-allowed;
      transform: none !important;
    }

    .login-link {
      color: rgba(255, 255, 255, 0.8);
      font-size: 1rem;
      text-align: center;
    }

    .login-link a {
      color: white;
      text-decoration: none;
      font-weight: 600;
      position: relative;
      transition: all 0.3s ease;
    }

    .login-link a::after {
      content: '';
      position: absolute;
      width: 0;
      height: 2px;
      bottom: -2px;
      left: 0;
      background: white;
      transition: width 0.3s ease;
    }

    .login-link a:hover {
      color: #f093fb;
    }

    .login-link a:hover::after {
      width: 100%;
    }

    /* Loading animation */
    .loading {
      position: relative;
      color: transparent !important;
    }

    .loading::after {
      content: '';
      position: absolute;
      width: 24px;
      height: 24px;
      top: 50%;
      left: 50%;
      margin-left: -12px;
      margin-top: -12px;
      border: 3px solid rgba(255, 255, 255, 0.3);
      border-radius: 50%;
      border-top-color: white;
      animation: spin 1s linear infinite;
    }

    @keyframes spin {
      to { transform: rotate(360deg); }
    }

    /* Form validation messages */
    .validation-message {
      font-size: 0.85rem;
      margin-top: 5px;
      padding: 8px 12px;
      border-radius: 8px;
      display: none;
    }

    .validation-error {
      background: rgba(239, 68, 68, 0.2);
      color: #fca5a5;
      border: 1px solid rgba(239, 68, 68, 0.3);
    }

    .validation-success {
      background: rgba(16, 185, 129, 0.2);
      color: #6ee7b7;
      border: 1px solid rgba(16, 185, 129, 0.3);
    }

    /* Mobile responsiveness */
    @media (max-width: 768px) {
      .heading {
        font-size: 2.2rem;
        margin-bottom: 30px;
      }
      
      .registration-card {
        padding: 40px 25px;
        margin: 10px;
      }
      
      .form-group input {
        padding: 16px 20px;
        font-size: 1rem;
      }
    }

    @media (max-width: 480px) {
      body {
        padding: 10px;
      }
      
      .heading {
        font-size: 1.8rem;
        margin-bottom: 25px;
      }
      
      .registration-card {
        padding: 30px 20px;
      }
    }

    /* Success animation */
    .success-animation {
      animation: successPulse 0.6s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    }

    @keyframes successPulse {
      0% { transform: scale(1); }
      50% { transform: scale(1.02); }
      100% { transform: scale(1); }
    }