<div class="row g-3">
                                <div class="col-sm-4">
                                    <label for="giorno_nascita" class="form-label">Giorno</label>
                                    <select id="giorno_nascita" class="form-select" name="giorno_nascita" required>
                                        <option value="">Giorno</option>
                                        <?php for ($i = 1; $i <= 31; $i++): ?>
                                        <option value="<?php echo $i; ?>"
                                            <?php echo isset($giorno) && $giorno == $i ? 'selected' : ''; ?>>
                                            <?php echo $i; ?>
                                        </option>
                                        <?php endfor; ?>
                                    </select>
                                </div>
                                <div class="col-sm-4">
                                    <label for="mese_nascita" class="form-label">Mese</label>
                                    <select id="mese_nascita" class="form-select" name="mese_nascita" required>
                                        <option value="">Mese</option>
                                        <?php for ($i = 1; $i <= 12; $i++): ?>
                                        <option value="<?php echo $i; ?>"
                                            <?php echo isset($mese) && $mese == $i ? 'selected' : ''; ?>>
                                            <?php echo mb_strtoupper(strftime('%B', mktime(0, 0, 0, $i, 10)), 'UTF-8'); ?>
                                        </option>
                                        <?php endfor; ?>
                                    </select>
                                </div>
                                <div class="col-sm-4">
                                    <label for="anno_nascita" class="form-label">Anno</label>
                                    <select id="anno_nascita" class="form-select" name="anno_nascita" required>
                                        <option value="">Anno</option>
                                        <?php for ($i = date('Y'); $i >= 1900; $i--): ?>
                                        <option value="<?php echo $i; ?>"
                                            <?php echo isset($anno) && $anno == $i ? 'selected' : ''; ?>>
                                            <?php echo $i; ?>
                                        </option>
                                        <?php endfor; ?>
                                    </select>
                                </div>
                            </div>