.base_back_top{position:fixed;right:40px;bottom:40px;width:50px;height:50px;border-radius:50%;background-color:#c0c4cc;color:#fff;display:flex;align-items:center;justify-content:center;cursor:pointer;opacity:0;visibility:hidden;transition:opacity .3s,visibility .3s;z-index:100}.base_back_top_visible{opacity:1;visibility:visible}.base_collapse_wrapper{width:100%;overflow:hidden}.base_collapse_header{padding:12px;background-color:#fff;cursor:pointer;font-weight:700;-webkit-user-select:none;-moz-user-select:none;user-select:none;display:flex;align-items:center;justify-content:space-between}.base_svg_rotated{transform:rotate(-180deg);transition:transform .3s ease}.base_collapse_outer{overflow:hidden;transition:height .3s ease;height:0}.base_collapse_inner{padding:12px;background-color:#fff;border-top:1px solid #ddd}