JSFiddle - React, Tailwind, and code Playground

HTML

<button>Submit</button><br>
<button class='rounded'>Submit</button>

CSS

button {
    background: #3498db;
    color: white;
    border: none;
    padding: 8px 20px;
    font-size: 16px;
    margin-bottom: 20px;
}

button.rounded {
    border-radius: 5px;
}