nutui/lib/plugin/cli/site/doc/compents/backtop/backtop.scss

.nut-backtop {
	display: none;
	line-height: 0;
	position: fixed;
	cursor: pointer;
	bottom: 20px;
	right: 10px;
	z-index: 1111;
	&.show {
		display: block;
	}
	&-main {
		transition: all 0.2s ease-in-out;
		width: 38px;
		height: 38px;
		background: #fff
			url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 31 39'%3E%3Cg fill-rule='evenodd'%3E%3Cpath d='M1.41 0C.63 0 0 .672 0 1.5S.63 3 1.41 3h28.18C30.37 3 31 2.328 31 1.5S30.369 0 29.59 0H1.41zM17 7.5a1.5 1.5 0 0 0-3 0v30a1.5 1.5 0 1 0 3 0v-30zM8.44 12.44l-8 8a1.5 1.5 0 1 0 2.12 2.12l8-8a1.5 1.5 0 1 0-2.12-2.12z'/%3E%3Cpath d='M16.56 6.44l14 14a1.5 1.5 0 1 1-2.12 2.12l-14-14a1.5 1.5 0 1 1 2.12-2.12z'/%3E%3C/g%3E%3C/svg%3E")
			no-repeat center;
		background-size: 20px 20px;
		border-radius: 50%;
		border: 2px solid rgba(180, 180, 180, 0.5);
		box-shadow: 0px 0px 2px 3px rgba(220, 220, 220, 0.1);
	}
	i {
		color: #fff;
		font-size: 24px;
		padding: 8px 12px;
		line-height: 0;
	}
}