(default)
<script>addBackToTop()</script>
<script>addBackToTop({
diameter: 56,
backgroundColor: 'rgb(255, 82, 82)',
textColor: '#fff'
})</script>
<script>addBackToTop({
diameter: 40,
backgroundColor: '#ddd',
textColor: 'red'
})</script>
<script>addBackToTop({
backgroundColor: '#fff',
innerHTML: 'Back to Top',
textColor: '#333'
})</script>
<style>
#back-to-top {
border: 1px solid #ccc;
border-radius: 0;
font-family: sans-serif;
font-size: 14px;
width: 100px;
text-align: center;
line-height: 30px;
height: 30px;
}
</style>
<script>addBackToTop({
backgroundColor: '#ffda0c',
innerHTML: '<svg viewBox="0 0 24 24"><path d="M4 12l1.41 1.41L11 7.83V20h2V7.83l5.58 5.59L20 12l-8-8-8 8z"/></svg>',
textColor: '#96071f'
})</script>