在APP.vue里面

.uni-tabbar__item:nth-child(4) .uni-tabbar__icon {
		width: 50px !important;
		height: 50px !important;
		position: relative;
		bottom: 30rpx;
	}
	.uni-tabbar__item:nth-child(4) .uni-tabbar__label {
		position: relative;
		bottom: 25rpx;
	}