组合样式布局
fx-center 垂直居中
fx-start 左对齐
fx-end 右对齐
fx-between 两侧对齐
fx-around 均分
fx-start col竖向
放大
fx-center wrap 可换行
fx-center时 自定义单个元素对齐方式
self-col-start
居中
self-col-end
单个样式布局
fx col-start row-start
fx col-center row-center
fx col-end row-end
fx col-center row-center col
fx col-center row-center col
self-col-start
2
self-col-end
fx col-center row-center wrap