$shadow-color: rgba(color(black), 0.1);
$shadow-size: rem(20px);
$shadow-bottom: inset 0 (-1 * $shadow-size) $shadow-size (-1 * $shadow-size) $shadow-color;
$shadow-top: inset 0 $shadow-size $shadow-size (-1 * $shadow-size) $shadow-color;

.p_r4 {
  -webkit-overflow-scrolling: touch;
}

.p_v1 {
  overflow-x: auto;
}

.p_ci {
  overflow-y: auto;
}

.p_mh {
  box-shadow: $shadow-top;
}

.p_yk {
  box-shadow: $shadow-bottom;
}

.p_mh.p_yk {
  box-shadow: $shadow-top, $shadow-bottom;
}