button Unusual Button Detail

They added a Text Block, then use this CSS to add circle line around text

#block-yui_3_17_2_1_1662396411392_1511168::before {
    content: '';
    position: absolute !important;
    width: 110%;
    height: 110%;
    background-image: url('https://static1.squarespace.com/static/5ff4deded948681ea2614e2c/t/63173fb4ce758a47b4dc2d20/1662468020675/button-outline.svg');
    background-size: contain;
    background-repeat: no-repeat;
    cursor: pointer !important;
    display: inline-block;
    margin: 0 auto !important;
    left: -6% !important;
    bottom: -6% !important
}

Use this tool to find text block id: https://chrome.google.com/webstore/detail/squarespace-id-finder/igjamfnifnkmecjidfbdipieoaeghcff?hl=en