JSFiddle - React, Tailwind, and code Playground

HTML

<div class='form-group-select'>
  <label class='control-label-select'>CENTRO DE CUSTO</label>
  <select name='banco' class='select form_campos_numeros'>
    <option value='0'></option>
    <option value='1'>custo</option>
    <option value='1'>custo</option>
  </select>
</div>


<div class='form-group'>
  <label class='control-label' for='numParcelas'>PARCELAS*</label>
  <input type='text' class='form_campos form_campos_numeros' id='numParcelas' name='numParcelas'>
</div>

CSS

body {
      font-family: Verdana;
      font-size: 12px;
    }
    
     .form-group {
      position: relative;
      display: flex;
      height: 45px;
      float: left;
      margin-right: 2px;
    }
    
    .control-label {
      opacity: 0.4;
      pointer-events: none;
      position: absolute;
      transform: translate3d(5px, 22px, 0) scale(1);
      transform-origin: left top;
      transition: 240ms;
      z-index: 2;
    }
    
    .form-group.focused .control-label {
      opacity: 1;
      transform: scale(0.75);
    }
    
    .form_campos {
      height: 20px;
      color: #484848;
      z-index: 1;
      align-self: flex-end;
      font-size: 15px;
      padding: 5px;
      outline: none;
      border-color: #484848;
      border-style: solid;
      border-bottom-width: 1px;
      border-top-width: 0;
      border-right-width: 0;
      border-left-width: 0;
      background: transparent;
    }
    
    .form_campos:hover,
    .form_campos:focus {
      border-color: #1E90FF;
    }
    
    .form_campos_numeros {
      width: 123px;
    }
    /* SELECT */
    
    .select {
      font-size: 15px;
      height: 31px;
      color: #484848;
      border-radius: 0px;
      border-color: #484848;
      border-style: solid;
      border-bottom-width: 1px;
      border-top-width: 0;
      border-right-width: 0;
      border-left-width: 0;
      -webkit-appearance: none;
      -moz-appearance: none;
      cursor: pointer;
      background: #ffffff;
      outline: none;
      margin-top: 14px;
      background: transparent;
      padding-right: 20px;
      text-overflow: ellipsis;
      overflow: hidden;
    }
    
    select::-ms-expand {
      display: none;
    }
    
    .select:hover,
    .select:focus {
      border-color: #1E90FF;
      border-style: solid;
      border-bottom-width: 1px;
      border-top-width: 0;
      border-right-width: 0;
      border-left-width: 0;
    }
    
    .control-label-select {
      position: absolute;
     ...

JavaScript

$('.form_campos').on('focus blur', function(e) {
  $(this).parents('.form-group').toggleClass('focused', (e.type === 'focus' || this.value.length > 0));
}).trigger('blur');

$('.form_campos_box').on('focus blur', function(e) {
  $(this).parents('.box').toggleClass('focused', (e.type === 'focus' || this.value.length > 0));
}).trigger('blur');