JSFiddle - React, Tailwind, and code Playground

HTML

<input name="nome_cliente" type="text" class="imv-frm-campo">
<input name="teste" type="text" class="imv-frm-campo">

CSS

.imv-frm-campo{
    width: 95%;
    font-size: 20px;
    padding: 10px;
    box-sizing: border-box;
    color: #333;
    margin-bottom: 10px;
    background-color: #D9ECF1;
    border: 0;
}

JavaScript

var inps = document.querySelectorAll("input")
for(var x=0; x<inps.length; x++){
   inps[x].oninput = function(e){
   
      if(e.target.name == "nome_cliente") var maxlen = 3;
      if(e.target.name == "teste") var maxlen = 5;
   
      this.style.backgroundColor = this.value.length >= maxlen ? "red" : "#D9ECF1";
   }
}