JSFiddle - React, Tailwind, and code Playground

HTML

<div class="panel-footer">
        <span style="width:100%;" class="header-footer-item">  
            <button class="align-right" type="button">Save</button>
        </span>    
    </div>

CSS

.panel-footer {
    height: 70px;
    border: solid;
    display:flex;
}

.header-footer-item {
    display: inline-block;
    border: solid red;
    text-align: right;
    align-self: center;

}