*{
        border-box: box-sizing;
        }
        body {
            font-family: Arial, sans-serif;
            display: flex;
            justify-content: center;
            align-items: center;
            flex-direction: column;
            min-height: 100vh;
            background-color: #f4f4f4;
            margin: 0;
            padding: 10px;
        }
        .container {
            background-color: white;
            padding: 20px;
            border-radius: 10px;
            box-shadow: 0 4px 8px rgba(0,0,0,0.2);
            text-align: center;
            width: 100%;
            max-width: 500px;
        }
        .logo {
            width: 100px;
            margin-bottom: 20px;
        }
        .button-group {
            margin: 20px 0;
            display: flex;
            flex-direction: column;
        }
        .button-group a {
            padding: 10px 20px;
            margin: 5px 0;
            border-radius: 5px;
            border: none;
            cursor: pointer;
            background-color: #007BFF;
            color: white;
            transition: background-color 0.3s;
            text-decoration: none;
        }
        .button-group a.active {
            background-color: #0056b3;
        }
        .button-group a:hover {
            background-color: #0056b3;
        }
        .form-group {
            margin-bottom: 15px;
            text-align: left;
        }
        label {
            display: block;
            margin-bottom: 5px;
            font-weight: bold;
        }
        input[type="file"], input[type="text"], input[type="password"] {
            width: 100%;
            padding: 8px;
            margin-top: 5px;
            box-sizing: border-box;
        }
        #enviar-btn {
            padding: 10px 20px;
            border: none;
            background-color: #007BFF;
            color: white;
            border-radius: 5px;
            cursor: pointer;
            width: 100%;
            margin-top: 10px;
        }
        #enviar-btn:hover {
            background-color: #0056b3;
        }
        /* Loader styles */
        .loader {
            border: 8px solid #f3f3f3; /* Light grey */
            border-top: 8px solid #3498db; /* Blue */
            border-radius: 50%;
            width: 50px;
            height: 50px;
            animation: spin 1s linear infinite;
            display: inline-block;
            margin-top: 20px;
        }
        @keyframes spin {
            0% { transform: rotate(0deg); }
            100% { transform: rotate(360deg); }
        }
        
        .modal {
            display: flex;
            justify-content: center;
            align-items: center;
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background-color: rgba(0, 0, 0, 0.5);
        }
        .modal-content {
            background-color: white;
            padding: 20px;
            border-radius: 5px;
            text-align: center;
        }
        .modal-content button {
            margin-top: 10px;
            padding: 10px 20px;
            background-color: #4CAF50;
            color: white;
            border: none;
            cursor: pointer;
            border-radius: 5px;
        }
        .modal-content button:hover {
            background-color: #45a049;
        }