how to style a buttpn css code example

Example 1: button style css

<div>
    <style scoped="">
        .button-success,
        .button-error,
        .button-warning,
        .button-secondary {
            color: white;
            border-radius: 4px;
            text-shadow: 0 1px 1px rgba(0, 0, 0, 0.2);
        }

        .button-success {
            background: rgb(28, 184, 65);
            /* this is a green */
        }

        .button-error {
            background: rgb(202, 60, 60);
            /* this is a maroon */
        }

        .button-warning {
            background: rgb(223, 117, 20);
            /* this is an orange */
        }

        .button-secondary {
            background: rgb(66, 184, 221);
            /* this is a light blue */
        }
    </style>
    <button class="button-success pure-button">Success Button</button>
    <button class="button-error pure-button">Error Button</button>
    <button class="button-warning pure-button">Warning Button</button>
    <button class="button-secondary pure-button">Secondary Button</button>
</div>

Example 2: button style css

<div class="pure-button-group" role="group" aria-label="...">
    <button class="pure-button">A Pure Button</button>
    <button class="pure-button">A Pure Button</button>
    <button class="pure-button pure-button-active">A Pure Button</button>
</div>