* {
      box-sizing: border-box;
    }

    html,
    body {
      margin: 0;
      padding: 0;
      height: 100%;
      font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
      overflow: hidden;
      background: #1c1c1c;
      color: #fff;
    }

    /* Fondo animado con gradiente gris oscuro */
    @keyframes gradientShift {
      0% {
        background-position: 0% 50%;
      }
      50% {
        background-position: 100% 50%;
      }
      100% {
        background-position: 0% 50%;
      }
    }

    body {
      background: linear-gradient(
        -45deg,
        #2a2a2a,
        #3d3d3d,
        #252525,
        #444444
      );
      background-size: 400% 400%;
      animation: gradientShift 15s ease infinite;
    }

    #bg-overlay {
      position: fixed;
      top: 0;
      left: 0;
      width: 100vw;
      height: 100vh;
      background: rgba(0, 44, 71, 0.85);
      z-index: -1;
    }

    /* Contenedor formulario */
    .login-container {
      max-width: 400px;
      margin: 80px auto;
      background-color: rgba(0, 44, 71, 0.88);
      padding: 40px 30px;
      border-radius: 12px;
      box-shadow: 0 8px 20px rgb(0 0 0 / 0.7);
      text-align: center;
      color: #fff;
      backdrop-filter: blur(10px);
      border: 1.5px solid rgba(255 255 255 / 0.2);
      position: relative;
      z-index: 1;
    }

    /* Logo limpio sin bordes ni sombra */
    .login-container img.logo {
      width: 110px;
      height: 110px;
      margin-bottom: 20px;
      border-radius: 50%;
      background-color: transparent;
      box-shadow: none;
      border: none;
      transition: none;
    }

    /* Título sin sombra ni bordes */
    .login-container h2 {
      margin-bottom: 30px;
      color: #ff6600;
      font-weight: 700;
      letter-spacing: 1.1px;
      text-shadow: none;
    }

    .input-group {
      position: relative;
      margin-bottom: 25px;
      text-align: left;
    }

    .input-group i {
      position: absolute;
      top: 12px;
      left: 10px;
      color: #ff6600;
      font-size: 18px;
      pointer-events: none;
    }

    .input-group input {
      width: 100%;
      padding: 10px 10px 10px 40px;
      border: none;
      border-bottom: 2px solid #ff6600;
      background: transparent;
      color: #fff;
      font-size: 16px;
      transition: border-color 0.3s ease;
    }

    .input-group input::placeholder {
      color: #ffc68c;
      opacity: 0.8;
    }

    .input-group input:focus {
      outline: none;
      border-color: #ffffff;
    }

    .login-container button {
      width: 100%;
      padding: 12px;
      background-color: #ff6600;
      color: #fff;
      border: none;
      border-radius: 8px;
      font-size: 16px;
      cursor: pointer;
      transition: background-color 0.3s ease, color 0.3s ease,
        border 0.3s ease;
      font-weight: 600;
      box-shadow: none;
    }

    .login-container button:hover,
    .login-container button:focus {
      background-color: #fff;
      color: #ff6600;
      border: 2px solid #ff6600;
      box-shadow: none;
      outline: none;
    }

    .login-links {
      margin-top: 20px;
      text-align: center;
    }

    .login-links a {
      color: #ffcc66;
      text-decoration: none;
      display: block;
      margin: 8px 0;
      font-size: 14px;
      transition: color 0.2s ease;
    }

    .login-links a:hover {
      color: #ffffff;
      text-decoration: underline;
    }

    @media (max-width: 480px) {
      .login-container {
        margin: 40px 20px;
        padding: 30px 20px;
      }
      .login-container img.logo {
        width: 90px;
        height: 90px;
      }
    }