两种颜色渐变：
<style>
.wrapper {
height: 100vh;
background-image: linear-gradient(to bottom right, #d834c2, #2088dd);
overflow: hidden;
}
</style>
三种颜色渐变：
<style>
.wrapper {
height: 100vh;
background-image: linear-gradient(to bottom right, #d819bf, #2683cf, #63e4b9);
overflow: hidden;
}
</style>