primevue-mirror/components/lib/scrolltop/style/ScrollTopStyle.js

import BaseStyle from 'primevue/base/style';

const theme = ({ dt }) => `
.p-scrolltop {
    position: fixed;
    bottom: 20px;
    right: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: ${dt('scrolltop.background')};
    color: ${dt('scrolltop.color')};
}

.p-scrolltop:hover {
    background: ${dt('scrolltop.hover.background')};
    color: ${dt('scrolltop.hover.text')};
}

.p-scrolltop-icon {
    font-size: 1.5rem;
    width: 1.5rem;
    height: 1.5rem;
}

.p-scrolltop-sticky {
    position: sticky;
}

.p-scrolltop-sticky {
    margin-left: auto;
}

.p-scrolltop-enter-from {
    opacity: 0;
}

.p-scrolltop-enter-active {
    transition: opacity 0.15s;
}

.p-scrolltop.p-scrolltop-leave-to {
    opacity: 0;
}

.p-scrolltop-leave-active {
    transition: opacity 0.15s;
}

.p-scrolltop {
    width: 3rem;
    height: 3rem;
    border-radius: 50%;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -2px rgba(0, 0, 0, 0.1);
    transition: background ${dt('transition.duration')}, color ${dt('transition.duration')}, outline-color ${dt('transition.duration')};
    outline-color: transparent;
}
`;

const classes = {
    root: ({ props }) => ['p-scrolltop p-link p-component', { 'p-scrolltop-sticky': props.target !== 'window' }],
    icon: 'p-scrolltop-icon'
};

export default BaseStyle.extend({
    name: 'scrolltop',
    theme,
    classes
});