JSFiddle - React, Tailwind, and code Playground
HTML
<form>
<label>Test PHPfrance :</label>
<input name="T2_PRE" type="text" class="Maj" pattern="^[A-ZÁÀÂÄÃÅÇÉÈÊËÍÌÎÏÑÓÒÔÖÕÚÙÛÜÝŸÆŒa-záàâäãåçéèêëíìîïñóòôöõúùûüýÿæœ '-]+$"/>
</form>
CSS
input:invalid {
outline: 2px solid red;
}