:root {
      --primary-color: #5a498d;
      --primary-soft: #f0eeff;
      --text-dark: #1a1a1a;
      --text-gray: #666666;
      --bg-light: #ffffff;
      --border-gray: #e5e7eb;
      --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
      --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.5), 0 4px 6px -2px rgba(0, 0, 0, 0.1);
    }

    body {
      background-color: #f9fafb;
      margin: 0;
      font-family: 'Inter', sans-serif;
      display: flex;
      align-items: center;
      justify-content: center;
      min-height: 100vh;
      color: var(--text-dark);
    }

    .login-container {
      width: 100%;
      max-width: 440px;
      padding: 20px;
      box-sizing: border-box;
    }

    .auth-card {
      background: var(--bg-light);
      padding: 48px 40px;
      border-radius: 24px;
      box-shadow: var(--shadow-lg);
      border: 1.5px solid var(--border-gray);
      text-align: center;
    }

    .brand-logo {
      width: 180px;
      margin-bottom: 32px;
      object-fit: contain;
    }

    .auth-header {
      margin-bottom: 32px;
    }

    .auth-title {
      font-size: 24px;
      font-weight: 700;
      letter-spacing: -0.5px;
      margin: 0 0 8px 0;
    }

    .auth-subtitle {
      font-size: 15px;
      color: var(--text-gray);
      line-height: 1.5;
    }

    .form-group {
      position: relative;
      margin-bottom: 24px;
      text-align: left;
    }

    .form-label {
      display: block;
      font-size: 14px;
      font-weight: 600;
      margin-bottom: 8px;
      color: var(--text-dark);
    }

    .input-wrapper {
      position: relative;
    }

    .form-input {
      width: 100%;
      height: 48px;
      padding: 0 16px 0 44px;
      font-size: 16px;
      background: #fff;
      border: 1px solid var(--border-gray);
      border-radius: 12px;
      box-sizing: border-box;
      outline: none;
      transition: all 0.2s ease;
      font-family: inherit;
    }

    .form-input:focus {
      border-color: var(--primary-color);
      box-shadow: 0 0 0 4px var(--primary-soft);
    }

    .input-icon {
      position: absolute;
      left: 14px;
      top: 50%;
      transform: translateY(-50%);
      font-size: 20px;
      color: #9ca3af;
      pointer-events: none;
    }

    .btn-submit {
      width: 100%;
      height: 48px;
      background-color: var(--primary-color);
      color: white;
      border: none;
      border-radius: 12px;
      font-size: 16px;
      font-weight: 600;
      cursor: pointer;
      transition: background-color 0.2s, transform 0.1s;
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
    }

    .btn-submit:hover {
      background-color: #4a3a75;
    }

    .btn-submit:active {
      transform: scale(0.98);
    }

    .auth-footer {
      margin-top: 32px;
      padding-top: 24px;
      border-top: 1px solid var(--border-gray);
    }

    .footer-link {
      color: var(--primary-color);
      text-decoration: none;
      font-size: 14px;
      font-weight: 500;
      transition: opacity 0.2s;
    }

    .footer-link:hover {
      opacity: 0.8;
      text-decoration: underline;
    }

    .copyright {
      margin-top: 40px;
      font-size: 12px;
      color: #9ca3af;
      text-align: center;
    }

    @media (max-width: 480px) {
      .auth-card {
        padding: 32px 24px;
        border-radius: 24px;
        box-shadow: var(--shadow-lg);
        border: 1.5px solid var(--border-gray);
        background: transparent;
      }
      body { background: #fff; }
  }