<style>
/* 屏幕小于1440px */
@media screen and (max-width: 1440px) {
	.add {
		width: 260px;
	}
}

/* 屏幕等于1440px */
@media screen and (max-width: 1440px) and (min-width: 1440px) {
	.add {
		width: 348px;
	}
}

/* 屏幕大于1440px */
@media screen and (min-width:1441px) {
	.add {
		width: 348px;
	}
}
</style>