.u-flex {
	display: flex;
	flex-direction: row;
	align-items: center;
}

/* 换行 */
.u-flex-wrap {
	flex-wrap: wrap;
}

/* 不换行 */
.u-flex-nowrap {
	flex-wrap: nowrap;
}

/* 垂直居中 */
.u-col-center {
	align-items: center;
}

/* 顶部对齐 */
.u-col-top {
	align-items: flex-start;
}

/* 底部对齐 */
.u-col-bottom {
	align-items: flex-end;
}

/* 左边对齐 */
.u-row-left {
	justify-content: flex-start;
}

/* 水平居中 */
.u-row-center {
	justify-content: center;
}

/* 右边对齐 */
.u-row-right {
	justify-content: flex-end;
}

/* 水平两端对齐，项目之间的间隔都相等 */
.u-row-between {
	justify-content: space-between;
}

/* 水平每个项目两侧的间隔相等，所以项目之间的间隔比项目与父元素两边的间隔大一倍 */
.u-row-around {
	justify-content: space-around;
}

.u-flex-1 {
	flex: 1;
}

.u-flex-2 {
	flex: 2;
}

.u-flex-3 {
	flex: 3;
}

.u-flex-4 {
	flex: 4;
}

.u-flex-5 {
	flex: 5;
}

.u-flex-6 {
	flex: 6;
}

.u-flex-7 {
	flex: 7;
}

.u-flex-8 {
	flex: 8;
}

.u-flex-9 {
	flex: 9;
}

.u-flex-10 {
	flex: 10;
}

.u-flex-11 {
	flex: 11;
}

.u-flex-12 {
	flex: 12;
}