:root {
      --primary-color: #2c3e50;
      --secondary-color: #3498db;
      --accent-color: #2980b9;
      --light-color: #f8f9fa;
      --dark-color: #34495e;
      --success-color: #27ae60;
    }
    
    body {
      background-color: #f5f7fa;
      font-family: 'Roboto', 'Segoe UI', system-ui, sans-serif;
      position: relative;
      overflow-x: hidden;
    }
    
    body::before {
      content: "";
      position: absolute;
      top: 0;
      left: 0;
      right: 0;
      height: 40vh;
      background: linear-gradient(135deg, var(--primary-color), var(--dark-color));
      z-index: -1;
      border-bottom-left-radius: 30% 20%;
      border-bottom-right-radius: 30% 20%;
    }
    
    .login-container {
      max-width: 420px;
      width: 100%;
      animation: fadeInUp 0.6s cubic-bezier(0.22, 1, 0.36, 1);
    }
    
    .login-card {
      border: none;
      border-radius: 12px;
      overflow: hidden;
      box-shadow: 0 15px 35px rgba(0, 0, 0, 0.1);
      transition: transform 0.3s ease;
    }
    
    .login-card:hover {
      transform: translateY(-5px);
    }
    
    .login-header {
      background: linear-gradient(to right, var(--primary-color), var(--dark-color));
      color: white;
      padding: 25px;
      text-align: center;
      position: relative;
    }
    
    .login-header::after {
      content: "";
      position: absolute;
      bottom: -10px;
      left: 0;
      right: 0;
      height: 20px;
      background: linear-gradient(to bottom right, transparent 49%, white 50%);
    }
    
    .brand-logo {
      width: 70px;
      height: 70px;
      margin: 0 auto 15px;
      display: flex;
      align-items: center;
      justify-content: center;
      background-color: white;
      border-radius: 18px;
      color: var(--primary-color);
      font-size: 28px;
      font-weight: bold;
      box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    }
    
    .login-header h1 {
      font-weight: 700;
      margin: 0;
      font-size: 1.8rem;
      letter-spacing: 0.5px;
    }
    
    .login-header p {
      margin: 8px 0 0;
      font-size: 0.95rem;
      opacity: 0.9;
      font-weight: 300;
    }
    
    .login-body {
      padding: 30px;
      background-color: white;
    }
    
    .form-control {
      border-radius: 8px;
      padding: 12px 15px;
      border: 1px solid #e0e0e0;
      transition: all 0.3s;
      font-size: 0.95rem;
    }
    
    .form-control:focus {
      border-color: var(--secondary-color);
      box-shadow: 0 0 0 0.2rem rgba(52, 152, 219, 0.15);
    }
    
    .form-label {
      font-weight: 500;
      color: var(--dark-color);
      margin-bottom: 8px;
      font-size: 0.95rem;
    }
    
    .btn-login {
      background: linear-gradient(to right, var(--secondary-color), var(--accent-color));
      border: none;
      padding: 12px;
      font-weight: 600;
      letter-spacing: 0.5px;
      transition: all 0.3s;
      border-radius: 8px;
      text-transform: uppercase;
      font-size: 0.9rem;
      box-shadow: 0 4px 6px rgba(52, 152, 219, 0.2);
    }
    
    .btn-login:hover {
      transform: translateY(-2px);
      box-shadow: 0 6px 12px rgba(52, 152, 219, 0.3);
    }
    
    .password-container {
      position: relative;
    }
    
    .toggle-password {
      position: absolute;
      right: 12px;
      top: 50%;
      transform: translateY(-50%);
      cursor: pointer;
      color: #95a5a6;
    }
    
    .toggle-password:hover {
      color: var(--secondary-color);
    }
    
    @keyframes fadeInUp {
      from { opacity: 0; transform: translateY(30px); }
      to { opacity: 1; transform: translateY(0); }
    }
    
    .footer-links {
      text-align: center;
      margin-top: 20px;
      font-size: 0.85rem;
    }
    
    .footer-links a {
      color: #7f8c8d;
      text-decoration: none;
      transition: color 0.3s;
    }
    
    .footer-links a:hover {
      color: var(--secondary-color);
    }
    
    .footer-links span {
      margin: 0 8px;
      color: #bdc3c7;
    }
    
    /* Efecto de carga para el botón */
    .btn-loading {
      position: relative;
      pointer-events: none;
    }
    
    .btn-loading::after {
      content: "";
      position: absolute;
      width: 16px;
      height: 16px;
      top: 0;
      left: 0;
      right: 0;
      bottom: 0;
      margin: auto;
      border: 3px solid transparent;
      border-top-color: white;
      border-radius: 50%;
      animation: spin 1s linear infinite;
    }
    
    @keyframes spin {
      to { transform: rotate(360deg); }
    }