$family: -apple-system, BlinkMacSystemFont, Helvetica Neue, PingFang SC,
  Microsoft YaHei, Simsun, Helvetica, Arial;
$fontsize: 14px;
$prefix: lg;

$space: 8px; //原件和原件，模块和模块之间的间隔空隙

$gutter-count: 12; //栅格列数
$gutter: $space; //栅格之间空隙
$radius: 2px; //公共圆角
$shadow: 0 0 5px 0 rgba(0, 0, 0, 0.5); //阴影UI?