效果图：
完整代码：
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8" />
<title>旋转方块加载动画</title>
<style type="text/css">
body {
background: #ECF0F1;
display: flex;
justify-content: center;
align-items: center;
height: 100vh;
margin: 0;
}
.spinner {
width: 40px;
height: 40px;
background-color: #3498db;
animation: spin 1s infinite linear;
}
@keyframes spin {
0% {
transform: rotate(0deg);
}
100% {
transform: rotate(360deg);
}
}
</style&
