code: function normalizePos (args) {
  	const point = {};
  	args.forEach((arg, i) => {
  		if (arg === "top") {
  			point.y = 0;
  		} else if (arg === "right") {
  			point.x = 100;
  		} else if (arg === "bottom") {
  			point.y = 100;
  		} else if (arg === "left") {
  			point.x = 0;
  		} else {
  			// 将长度单位转换为坐标
  			point[i ? "y" : "x"] = parseLength(arg);
  		}
  	});
  	return point;
  }
docs: 分析css参数中的坐标信息
  @param   {String[]} args  包含坐标信息的两个字符串组成的数组
  @returns {Int} x          [x轴坐标]
  @returns {Int} y          [y轴坐标]