React

HTML

<div id="app"></div>

CSS

body {
  background: #20262E;
  padding: 20px;
  font-family: Helvetica;
}

#app {
  background: #fff;
  border-radius: 4px;
  padding: 20px;
  transition: all 0.2s;
}

li {
  margin: 8px 0;
}

h2 {
  font-weight: bold;
  margin-bottom: 15px;
}

.done {
  color: rgba(0, 0, 0, 0.3);
  text-decoration: line-through;
}

input {
  margin-right: 5px;
}

React

function Hello() {
    const [value, setValue] = React.useState("");
    
    function handleChange(event) {
      let value = event.target.value;
    	setTimeout(() => setValue(value), 100);
    }
    
    return (
      <div>
        Type here:
        <input value={value} onChange={handleChange}/>
      </div>
    );
}

ReactDOM.render(
  <Hello/>,
  document.getElementById('app')
);