:root {
      --primary-color: #17375D;
      --primary-dark: #3a56d4;
      --primary-light: #4895ef;
      --secondary-color: #1e293b;
      --success-color: #06d6a0;
      --warning-color: #ffd166;
      --danger-color: #ef476f;
      --light-bg: #f8f9fa;
      --dark-bg: #0a0f1e;
      --card-bg-light: rgba(255, 255, 255, 0.95);
      --card-bg-dark: rgba(17, 25, 40, 0.95);
      --card-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
      --card-shadow-hover: 0 30px 60px -12px rgba(0, 0, 0, 0.3);
      --transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
      --gradient-primary: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
      --gradient-dark: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
    }


    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }

    body {
      font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
      background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
      min-height: 100vh;
      max-width: 100vw;
      display: flex;
      align-items: center;
      justify-content: center;
      transition: background 0.5s ease;
      position: relative;
      overflow-x: hidden;
      overflow: hidden;
    }

    .particles,
    body::before {
      overflow: hidden;
    }

    /* Fondo con partículas animadas */
    body::before {
      content: '';
      position: absolute;
      top: 0;
      left: 0;
      right: 0;
      bottom: 0;
      background: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100" opacity="0.1"><circle cx="10" cy="10" r="2" fill="white"/><circle cx="90" cy="30" r="3" fill="white"/><circle cx="30" cy="80" r="2" fill="white"/><circle cx="70" cy="70" r="4" fill="white"/><circle cx="50" cy="20" r="2" fill="white"/></svg>');
      background-size: 200px 200px;
      animation: float 20s linear infinite;
      pointer-events: none;
    }

    body.dark-mode {
      background: var(--gradient-dark);
    }

    body.dark-mode::before {
      opacity: 0.05;
    }

    @keyframes float {
      0% {
        transform: translateY(0) rotate(0deg);
      }

      50% {
        transform: translateY(-20px) rotate(180deg);
      }

      100% {
        transform: translateY(0) rotate(360deg);
      }
    }

    .login-container {
      width: 100%;
      max-width: 480px;
      position: relative;
      z-index: 10;
      animation: fadeInUp 0.8s ease-out;
    }

    .login-card {
      background: var(--card-bg-light);
      backdrop-filter: blur(20px);
      border-radius: 32px;
      border: 1px solid rgba(255, 255, 255, 0.2);
      box-shadow: var(--card-shadow);
      overflow: hidden;
      transition: var(--transition);
      position: relative;
    }

    .dark-mode .login-card {
      background: var(--card-bg-dark);
      border-color: rgba(255, 255, 255, 0.05);
      box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
    }

    .login-card:hover {
      box-shadow: var(--card-shadow-hover);
      transform: translateY(-8px) scale(1.02);
    }

    .card-header {
      background: var(--gradient-primary);
      color: white;
      text-align: center;
      padding: 3rem 2rem;
      border-bottom: none;
      position: relative;
      overflow: hidden;
    }

    .card-header::before {
      content: '';
      position: absolute;
      top: -50%;
      right: -50%;
      width: 200%;
      height: 200%;
      background: radial-gradient(circle, rgba(255, 255, 255, 0.2) 0%, transparent 70%);
      animation: rotate 20s linear infinite;
    }

    @keyframes rotate {
      from {
        transform: rotate(0deg);
      }

      to {
        transform: rotate(360deg);
      }
    }

    .card-header h1 {
      font-weight: 700;
      font-size: 2rem;
      margin-bottom: 0.5rem;
      position: relative;
      text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.2);
    }

    .card-header p {
      font-weight: 300;
      opacity: 0.95;
      position: relative;
      font-size: 1.1rem;
    }

    .card-body {
      padding: 2.5rem;
    }

    .form-label {
      font-weight: 600;
      color: #1e293b;
      margin-bottom: 0.5rem;
      font-size: 0.9rem;
      text-transform: uppercase;
      letter-spacing: 0.5px;
    }

    .dark-mode .form-label {
      color: #cbd5e1;
    }

    .input-group {
      margin-bottom: 1.5rem;
      position: relative;
    }

    .input-group-text {
      background-color: #f1f5f9;
      border: 2px solid #e2e8f0;
      border-right: none;
      color: #64748b;
      border-radius: 16px 0 0 16px;
      padding: 0.75rem 1.25rem;
      transition: var(--transition);
    }

    .dark-mode .input-group-text {
      background-color: #1e293b;
      border-color: #334155;
      color: #94a3b8;
    }

    .form-control {
      padding: 0.875rem 1.25rem;
      border-radius: 0 16px 16px 0;
      border: 2px solid #e2e8f0;
      border-left: none;
      background-color: #f8fafc;
      font-size: 1rem;
      transition: var(--transition);
    }

    .form-control:focus {
      border-color: var(--primary-color);
      box-shadow: none;
      background-color: white;
    }

    .dark-mode .form-control {
      background-color: #0f172a;
      border-color: #334155;
      color: #f1f5f9;
    }

    .dark-mode .form-control:focus {
      background-color: #1e293b;
      border-color: var(--primary-light);
    }

    .input-group:focus-within .input-group-text {
      border-color: var(--primary-color);
      color: var(--primary-color);
    }

    .input-group:focus-within .form-control {
      border-color: var(--primary-color);
    }

    .form-text {
      color: #64748b;
      font-size: 0.875rem;
      margin-top: 0.5rem;
      padding-left: 0.5rem;
    }

    .dark-mode .form-text {
      color: #94a3b8;
    }

    .btn {
      padding: 1rem 1.5rem;
      font-weight: 600;
      border-radius: 16px;
      transition: var(--transition);
      position: relative;
      overflow: hidden;
      border: none;
      text-transform: uppercase;
      letter-spacing: 0.5px;
      font-size: 0.95rem;
    }

    .btn::before {
      content: '';
      position: absolute;
      top: 50%;
      left: 50%;
      width: 0;
      height: 0;
      border-radius: 50%;
      background: rgba(255, 255, 255, 0.3);
      transform: translate(-50%, -50%);
      transition: width 0.6s, height 0.6s;
    }

    .btn:hover::before {
      width: 300px;
      height: 300px;
    }

    .btn-primary {
      background: var(--gradient-primary);
      color: white;
    }

    .btn-primary:hover {
      background: linear-gradient(135deg, var(--primary-dark) 0%, var(--secondary-color) 100%);
      transform: translateY(-4px);
      box-shadow: 0 15px 30px -10px var(--primary-color);
    }

    .btn-outline-secondary {
      background: transparent;
      border: 2px solid #e2e8f0;
      color: #64748b;
    }

    .dark-mode .btn-outline-secondary {
      border-color: #475569;
      color: #94a3b8;
    }

    .btn-outline-secondary:hover {
      background: #f1f5f9;
      border-color: #94a3b8;
      color: #475569;
      transform: translateY(-4px);
    }

    .dark-mode .btn-outline-secondary:hover {
      background: #334155;
      border-color: #64748b;
      color: #cbd5e1;
    }

    .divider {
      display: flex;
      align-items: center;
      margin: 2rem 0;
      color: #94a3b8;
    }

    .divider::before,
    .divider::after {
      content: "";
      flex: 1;
      height: 2px;
      background: linear-gradient(90deg, transparent, #e2e8f0, transparent);
    }

    .dark-mode .divider::before,
    .dark-mode .divider::after {
      background: linear-gradient(90deg, transparent, #475569, transparent);
    }

    .divider span {
      padding: 0 1.5rem;
      font-size: 0.9rem;
      font-weight: 500;
      text-transform: uppercase;
    }

    .alert {
      border-radius: 16px;
      border: none;
      padding: 1.25rem;
      animation: slideInDown 0.4s ease-out;
      font-weight: 500;
    }

    .alert-danger {
      background: rgba(239, 71, 111, 0.1);
      color: #b91c1c;
      border-left: 4px solid var(--danger-color);
    }

    .dark-mode .alert-danger {
      background: rgba(239, 71, 111, 0.2);
      color: #fecaca;
    }

    .alert-success {
      background: rgba(6, 214, 160, 0.1);
      color: #065f46;
      border-left: 4px solid var(--success-color);
    }

    .dark-mode .alert-success {
      background: rgba(6, 214, 160, 0.2);
      color: #a7f3d0;
    }

    .footer-text {
      font-size: 0.875rem;
      color: #64748b;
      text-align: center;
      margin-top: 2rem;
      padding-top: 2rem;
      border-top: 2px solid #e2e8f0;
    }

    .dark-mode .footer-text {
      color: #94a3b8;
      border-top-color: #334155;
    }

    .footer-text a {
      color: var(--primary-color);
      font-weight: 600;
      text-decoration: none;
      position: relative;
    }

    .footer-text a::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--gradient-primary);
      transition: width 0.3s ease;
    }

    .footer-text a:hover::after {
      width: 100%;
    }

    .logo-container {
      text-align: center;
      margin-bottom: 2rem;
      position: relative;
    }

    .logo {
      height: 70px;
      width: auto;
      filter: drop-shadow(0 10px 15px rgba(0, 0, 0, 0.2));
      animation: pulse 2s infinite;
    }

    @keyframes pulse {

      0%,
      100% {
        transform: scale(1);
      }

      50% {
        transform: scale(1.05);
      }
    }

    .loading-spinner {
      display: none;
      width: 24px;
      height: 24px;
      border: 3px solid rgba(255, 255, 255, 0.3);
      border-radius: 50%;
      border-top-color: white;
      animation: spin 0.8s linear infinite;
      margin-left: 10px;
    }

    .btn-primary:disabled .loading-spinner {
      display: inline-block;
    }

    @keyframes fadeInUp {
      from {
        opacity: 0;
        transform: translateY(30px);
      }

      to {
        opacity: 1;
        transform: translateY(0);
      }
    }

    @keyframes slideInDown {
      from {
        opacity: 0;
        transform: translateY(-20px);
      }

      to {
        opacity: 1;
        transform: translateY(0);
      }
    }

    @keyframes slideInUp {
      from {
        opacity: 0;
        transform: translateY(20px);
      }

      to {
        opacity: 1;
        transform: translateY(0);
      }
    }

    @keyframes spin {
      to {
        transform: rotate(360deg);
      }
    }

    /* Estilos para validación */
    .is-valid {
      border-color: var(--success-color) !important;
    }

    .is-invalid {
      border-color: var(--danger-color) !important;
    }

    /* Responsive */
    @media (max-width: 576px) {
      .card-body {
        padding: 2rem 1.5rem;
      }

      .card-header {
        padding: 2rem 1.5rem;
      }

      .btn {
        padding: 0.875rem 1.25rem;
      }

    }

    /* Efecto de partículas */
    .particles {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      z-index: 1;
      pointer-events: none;
    }

    .particle {
      position: absolute;
      width: 4px;
      height: 4px;
      background: rgba(255, 255, 255, 0.5);
      border-radius: 50%;
      animation: particleFloat 10s infinite;
    }

    @keyframes particleFloat {

      0%,
      100% {
        transform: translateY(0) translateX(0);
        opacity: 0;
      }

      10% {
        opacity: 1;
      }

      90% {
        opacity: 1;
      }

      100% {
        transform: translateY(-100vh) translateX(100px);
        opacity: 0;
      }
    }/ *   B o t o n   c l a r o   /   o s c u r o   * / 
 . t h e m e - t o g g l e   { 
     p o s i t i o n :   f i x e d ; 
     b o t t o m :   2 0 p x ; 
     r i g h t :   2 0 p x ; 
     b a c k g r o u n d :   l i n e a r - g r a d i e n t ( 1 3 5 d e g ,   v a r ( - - p r i m a r y - d a r k )   0 % ,   v a r ( - - p r i m a r y - d a r k )   1 0 0 % ) ; 
     c o l o r :   w h i t e ; 
     w i d t h :   5 0 p x ; 
     h e i g h t :   5 0 p x ; 
     b o r d e r - r a d i u s :   5 0 % ; 
     d i s p l a y :   f l e x ; 
     a l i g n - i t e m s :   c e n t e r ; 
     j u s t i f y - c o n t e n t :   c e n t e r ; 
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     t r a n s i t i o n :   a l l   0 . 3 s   e a s e ; 
 } 
 
 . t h e m e - t o g g l e : h o v e r   { 
     t r a n s f o r m :   s c a l e ( 1 . 1 ) ; 
     b o x - s h a d o w :   0   6 p x   2 0 p x   r g b a ( 0 ,   0 ,   0 ,   0 . 2 ) ; 
 } 
 
 . t h e m e - t o g g l e   i   { 
     f o n t - s i z e :   1 . 2 5 r e m ; 
 } 
 
 / *   B o t o n   s e l e c t o r   d e   i d i o m a   * / 
 . l a n g - t o g g l e   { 
     p o s i t i o n :   f i x e d ; 
     b o t t o m :   8 0 p x ; 
     r i g h t :   2 0 p x ; 
     b a c k g r o u n d :   l i n e a r - g r a d i e n t ( 1 3 5 d e g ,   v a r ( - - p r i m a r y - d a r k )   0 % ,   v a r ( - - p r i m a r y - d a r k )   1 0 0 % ) ; 
     c o l o r :   w h i t e ; 
     w i d t h :   5 0 p x ; 
     h e i g h t :   5 0 p x ; 
     b o r d e r - r a d i u s :   5 0 % ; 
     d i s p l a y :   f l e x ; 
     a l i g n - i t e m s :   c e n t e r ; 
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     b o x - s h a d o w :   0   4 p x   1 2 p x   r g b a ( 0 ,   0 ,   0 ,   0 . 1 5 ) ; 
     z - i n d e x :   1 0 5 0 ; 
     t r a n s i t i o n :   a l l   0 . 3 s   e a s e ; 
 } 
 
 . l a n g - t o g g l e : h o v e r   { 
     t r a n s f o r m :   s c a l e ( 1 . 1 ) ; 
     b o x - s h a d o w :   0   6 p x   2 0 p x   r g b a ( 0 ,   0 ,   0 ,   0 . 2 ) ; 
 } 
 
 . l a n g - t o g g l e   s p a n   { 
     f o n t - s i z e :   1 . 2 5 r e m ; 
 }  
 