Styled loading bar animation

Loading.js

import styled, { keyframes } from "styled-components"

const slide = keyframes`
  0% { left: -35%; right: 100%; }
  60% { left: 100%; right: -90%; }
  100% { left: 100%; right: -90%; }
`

const chase = keyframes`
  0% { left: -200%; right: 100%; }
  60% { left: 107%; right: -8%; }
  100% { left: 107%; right: -8%; }
`

const Loading = styled.div`
  display: inline-block;
  position: relative;
  background: #ddd;
  background-clip: padding-box;
  border-radius: 2em;
  width: ${props => props.width || "100%"};
  height: ${props => props.height || "0.6em"};
  overflow: hidden;

  &::before,
  &::after {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    bottom: 0;
    will-change: left, right;
    background: #000;
    background-clip: padding-box;
    border-radius: 2em;
    opacity: 0.1;
  }
  &::before {
    animation: ${slide} 3s cubic-bezier(0.65, 0.815, 0.735, 0.395) infinite;
  }
  &::after {
    animation: ${chase} 3s cubic-bezier(0.165, 0.84, 0.44, 1) infinite;
    animation-delay: 1.5s;
  }
`