字体渐变色
.font2 {
display: inline-block;
font-family: '微软雅黑';
font-size: 10em;
position: relative;
}
.font2::after {
content: attr(data-text);
color: green;
position: absolute;
left: 0;
z-index: 2;
-webkit-mask-image: -webkit-gradient(linear, 0 0, 0 bottom, from(#ff0000), to(rgba(0, 0, 255, 0)));
}