[рони]

skwz,

{
  let classNamesRE = /^(?:start|stop|status)$/;
  let input = document.getElementById("my-field");
  let div = document.querySelector(".sos");

  let onInputHandler = event => {
    let val = event.target.value.trim();
    let match = event.code === "Enter" && val ? (val.match(classNamesRE)||"error") : "";
    event.target.className = div.className = "sos " + match;
  };

  input.addEventListener("keyup", onInputHandler);
};