 body {
            margin: 0; padding: 0;
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            min-height: 100vh; display: flex; justify-content: center; align-items: center;
            background: linear-gradient(270deg, #001f3f, #0074D9, #00aaff);
            background-size: 600% 600%;
            animation: gradiente 15s ease infinite;
            color: white; padding: 40px 20px;
        }
        @keyframes gradiente {
            0% { background-position: 0% 50%; }
            50% { background-position: 100% 50%; }
            100% { background-position: 0% 50%; }
        }
        .container {
            width: 100%; max-width: 600px;
            background: rgba(0, 0, 0, 0.7);
            padding: 50px; border-radius: 30px;
            box-shadow: 0 0 25px rgba(0,200,255,0.6);
            animation: fadeIn 1.5s ease-out;
        }
        @keyframes fadeIn {
            from { opacity: 0; transform: translateY(30px); }
            to { opacity: 1; transform: translateY(0); }
        }
        h2 {
            text-align: center; color: #00cfff;
            text-shadow: 0 0 15px rgba(0,200,255,0.8);
            margin-bottom: 30px;
        }
        label {
            display: block; margin: 12px 0 6px;
            font-weight: bold; color: #00cfff;
        }
        input, select {
            width: 100%; padding: 12px;
            border: none; border-radius: 10px;
            font-size: 1rem; margin-bottom: 15px;
            outline: none; box-shadow: inset 0 0 8px rgba(0,200,255,0.4);
        }
        input:focus, select:focus {
            box-shadow: 0 0 15px rgba(0,255,200,0.7);
        }
        .btn {
            width: 100%; background: linear-gradient(125deg, #00cfff, #0077ff);
            border: none; border-radius: 20px;
            padding: 14px; font-size: 1.2rem;
            color: white; cursor: pointer;
            transition: all 0.3s ease;
            box-shadow: 0 0 20px rgba(0,200,255,0.8), 0 0 40px rgba(0,200,255,0.4);
        }
        .btn:hover {
            transform: scale(1.05);
            background: linear-gradient(20deg, #00ffcc, #0077ff);
            box-shadow: 0 0 30px rgba(0,155,200,0.9), 0 0 60px rgba(0,100,155,0.7);
        }
        #campoGrado { display: none; }

        /* campo contraseña con icono */
        .password-container {
            position: relative;
        }
        .toggle-password {
            position: absolute;
            right: -20px;
            top:35%;
            transform: translateY(-50%);
            cursor: pointer;
            color: #00cfff;
            font-size: 1.2rem;
        }
    </style>
</head>
<body>
    <div class="container">
        <h2>Formulario de Registro</h2>
        <form method="POST">
            <label>Cédula / Identificación:</label>
            <input type="text" name="Cod_identificacion" required>

            <label>Nombre Completo:</label>
            <input type="text" name="Nombre" required>

            <label>Correo:</label>
            <input type="email" name="Correo" required>

            <label>Contacto:</label>
            <input type="text" name="Contacto" required>

            <label>Contraseña:</label>
            <div class="password-container">
                <input type="password" name="Contrasena" id="Contrasena" required>
                <span class="toggle-password" onclick="togglePassword()">👁️</span>
            </div>
            
            <label>Discapacidad:</label>
            <select name="Cod_riesgo" id="discapacidad" required>
                <option value="">Seleccione...</option>
                <?php while ($row = $tipos_discapacidad->fetch_assoc()) { ?>
                    <option value="<?php echo $row['Codigo']; ?>">
                        <?php echo $row['Descripcion']; ?>
                    </option>
                <?php } ?>
            </select>


            <label>Tipo de Usuario:</label>
            <select name="Cod_Tipo_usuario" id="tipoUsuario" required>
                <option value="">Seleccione...</option>
                <?php while ($row = $tipos_usuario->fetch_assoc()) { ?>
                    <option value="<?php echo $row['Codigo']; ?>">
                        <?php echo $row['Descripcion']; ?>
                    </option>
                <?php } ?>
            </select>

            <div id="campoGrado">
                <label>Grado:</label>
                <select name="Cod_grado" id="gradoSelect">
                    <option value="">Seleccione...</option>
                    <option value="1">Preescolar</option>
                    <option value="2">Primero</option>
                    <option value="3">Segundo</option>
                    <option value="4">Tercero</option>
                    <option value="5">Cuarto</option>
                    <option value="6">Quinto</option>
                    <option value="7">Sexto</option>
                    <option value="8">Séptimo</option>
                    <option value="9">Octavo</option>
                    <option value="10">Noveno</option>
                    <option value="11">Décimo</option>
                    <option value="12">Once</option>
                    <option value="13">No Aplica...</option>
                </select>
            </div>

            <button class="btn" type="submit">Guardar Usuario</button> 
            <br>
            <br>
            
            
             <button type="button" class="btn" onclick="window.location.href='index.html'">
             Volver al inicio 🚪
            </button>

        </form>
    </div>

    <script>
        // Mostrar u ocultar el campo "Grado" según el tipo de usuario
        document.getElementById('tipoUsuario').addEventListener('change', function() {
            const campoGrado = document.getElementById('campoGrado');
            const gradoSelect = document.getElementById('gradoSelect');
            const tipo = this.options[this.selectedIndex].text.toLowerCase();

            if (tipo.includes('docente') || tipo.includes('estudiante')) {
                campoGrado.style.display = 'block';
                gradoSelect.required = tipo.includes('estudiante');
            } else {
                campoGrado.style.display = 'none';
                gradoSelect.required = false;
                gradoSelect.value = '';
            }
        });

        // Mostrar/ocultar contraseña
        function togglePassword() {
            const input = document.getElementById("Contrasena");
            input.type = (input.type === "password") ? "text" : "password";
        }