I've currently tried to integrate bootstrap into my project, and so far it does not look at all as I intended in the first place, this is what I have...
<%@page contentType="text/html" pageEncoding="UTF-8"%>
<%@taglib prefix="s" uri="/struts-tags"%>
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css" integrity="sha384-ggOyR0iXCbMQv3Xipma34MD+dH/1fQ784/j6cY/iJTQUOhcWr7x9JvoRxT2MZw1T" crossorigin="anonymous">
<link rel="stylesheet" href="bootsrap/css/style.css">
<link href="https://fonts.googleapis.com/css?family=Roboto+Condensed&display=swap" rel="stylesheet">
<script src="https://code.jquery.com/jquery-3.3.1.slim.min.js" integrity="sha384-q8i/X+965DzO0rT7abK41JStQIAqVgRVzpbzo5smXKp4YfRvH+8abtTE1Pi6jizo" crossorigin="anonymous"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.7/umd/popper.min.js" integrity="sha384-UO2eT0CpHqdSJQ6hJty5KVphtPhzWj9WO1clHTMGa3JDZwrnQq4sF86dIHNDz0W1" crossorigin="anonymous"></script>
<script src="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/js/bootstrap.min.js" integrity="sha384-JjSmVgyd0p3pXB1rRibZUAYoIIy6OrQ6VrjIEaFf/nJGzIxFDsf4x0xIM+B07jRM" crossorigin="anonymous"></script>
<title>JSP Page</title>
</head>
<body>
<div class="container">
<s:form action="registrar" theme="simple" cssClass="well form-horizontal">
<s:textfield label="ID Asignación" placeholder="ID Unidad" name="u.ID"></s:textfield>
<s:textfield label="Nombre Asignación" name="u.NombreUA"></s:textfield>
<s:textfield label="Tipo cuota" name="u.TipoCuota"></s:textfield>
<s:textfield label="Grupo cuota" name="u.GrupoCuota"></s:textfield>
<s:textfield label="Fecha Inicio" name="u.FechaInic"></s:textfield>
<s:textfield label="Grupo Fecha término" name="u.FechaTerm"></s:textfield>
<s:textfield label="Región/Macrozona" name="u.RegionM"></s:textfield>
<s:textfield label="Imputación conjunta" name="u.ImpConj"></s:textfield>
<s:submit value="Registrar"></s:submit>
</s:form>
</div>
</body>
</html>
Which looks like this...