JSFiddle - React, Tailwind, and code Playground

HTML

<div class="task_hours_day">
  <div class="task" data-size="144">
    <div class="content_task">
      <span class="id_task">3121</span>
      <span class="time_task">1h</span>
    </div>
  </div>
  <div class="task" data-size="144">
    <div class="content_task">
      <span class="id_task">3122</span>
      <span class="time_task">1h</span>
    </div>
  </div>
  <div class="task" data-size="144">
    <div class="content_task">
      <span class="id_task">3123</span>
      <span class="time_task">1h</span>
    </div>
  </div>
  <div class="task" data-size="144">
    <div class="content_task">
      <span class="id_task">3124</span>
      <span class="time_task">1h</span>
    </div>
  </div>
</div>

CSS

.task_hours_day{
    width: 100%;
    display:block;
}
.task:first-child { 
    border-top-left-radius: 10px;
    border-bottom-left-radius: 10px;
}
.task:last-child { 
    border-top-right-radius: 10px;
    border-bottom-right-radius: 10px;
}
.task{
    background:red;
    font-size: 12px;
    font-weight: normal;
    display: inline-block;
    height: 13vw;
    overflow: hidden;
    margin-left: 5px;
    float: left;
}

JavaScript

//attribu la taille à chaque rectangle
 $('.task').each(function() {
   var size = $(this).data("size");
   $( this ).css('width',size);
});

//Reinit la taille du bloc .active
function resetActiveWidth(){
	//On récupère l'élement .active
	var activeElement = $(".active");
  //On récupère la taille
  var size = activeElement.data('size');
  
  //On définit sa nouvelle taille
  //Taille actuelle -20% de size
  activeElement.animate({
    width: "-=" + size * 1.2
  });
  
  //On supprile sa classe active
  activeElement.removeClass('active');
}

var stop = false;
//quand on click sur un rectangle
$('.task').click(function () {
  if(!stop) {
    stop = true;
    //si la tache n'est pas active
    if(!$(this).hasClass('active')){
      resetActiveWidth();

      var size = $(this).width();
      //ajoute les 20% à la taille
      size = size * 1.2;
      $(this).addClass('active');
      $(this).animate({
        width: "+=" + size
      });
    }

    stop = false;
  }
});