修改nginx.conf文件

server
    {
        listen 80 default_server reuseport;
        #listen [::]:80 default_server ipv6only=on;
        server_name _;
        return 500;
        access_log  /home/wwwlogs/access.log;
    }

server
    {
        listen 443 ssl http2 default_server reuseport;
        #listen [::]:443 default_server ipv6only=on;
        server_name _;
        ssl_certificate /usr/local/nginx/conf/ssl/default.pem;
        ssl_certificate_key /usr/local/nginx/conf/ssl/default.key;
        return 500;
        access_log  /home/wwwlogs/access.log;
    }

OpenWrt改源码的话，在feeds/luci/collections/luci/Makefile文件夹下面Makefile文件里面，找到LUCI_DEPENDS这一项，替换luci-theme-bootstrap为你想要的主题，里填入luci-theme-argon，然后重新更新安装feeds，在make menuconfig里面就默认选中你要的主题了，也会默认启用。

vi feeds/luci/collections/luci/Makefile