html {
  font-size: 62.5%; /* 16px * 62.5% = 10px */
  width: 100%;
  box-sizing: border-box;
}
body {
  list-style: none;
}
.s__br {
  display: none;
}
@media (max-width: 850px) {
  .s__br {
    display: block;
  }
}