* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}
html,
body {
  width: 100%;
  background: #f5f5f5;
  -webkit-text-size-adjust: 100%;
  font-family: -apple-system, BlinkMacSystemFont, "Helvetica Neue", Arial,
    "PingFang SC", "Microsoft YaHei", sans-serif;
}
img {
  border: 0;
}