Ghost/ghost/members-auth-pages/components/FormSubmit.js

export default ({onClick, buttonClass, showSpinner, disabled, label}) => (
    <div className="mt7">
        <button type="submit" className={ (buttonClass ? buttonClass : 'gm-btn-blue') } onClick={onClick} disabled={ ((disabled || showSpinner) ? 'disabled' : '') }>
            <span>
                { (showSpinner ? <span className="gm-spinner"></span> : '')}
                { label }
            </span>
        </button>
    </div>
);