将svg文件内容转义之后 加上前缀data:image/svg+xml;utf8,
来装载
.el-icon-arrow-down::before {
content: url("data:image/svg+xml,%3Csvg t='1610605001506' class='icon' viewBox='0 0 1024 1024' version='1.1' xmlns='http://www.w3.org/2000/svg' p-id='9843' xmlns:xlink='http://www.w3.org/1999/xlink' width='16' height='16'%3E%3Cdefs%3E%3Cstyle type='text/css'%3E%3C/style%3E%3C/defs%3E%3Cpath d='M562.005333 512l-211.2-211.2 60.330667-60.330667L682.666667 512l-271.530667 271.530667-60.330667-60.330667z' p-id='9844' fill='%239DA1A7'%3E%3C/path%3E%3C/svg%3E");
}
参考链接 技术细节详情 https://www.zhangxinxu.com/wordpress/2018/08/css-svg-background-image-base64-encode/
svg转化工具1 https://www.zhangxinxu.com/sp/svg-text.php
svg转化工具2 https://tool.oschina.net/encode?type=4