nginx反代filebrowse，不能正常显示页面_美国VPS

因为filebrowser启用后用的是端口2345，对应的本地地址是localhost:2345,但是用nginx反代后不能正常显示页面，对应的反带地址a.b.com一直在页面循环滚动，不能显示。F12后台查看css，js都是404的，有大佬能指点一下吗？

server
{
      listen 80;
#listen [::]:80;
server_name a.b.com ;
location / {          b.com/$1redirect;    }
location ~ /.well-known {
allow all;                                           }
location ~ /\.    {
deny all;                                              }
access_log  /home/wwwlogs/a.b.com.log;       }

server
{
   listen 443 ssl http2;
   #listen [::]:443 ssl http2;
   server_name a.b.com ;
      location / {
      proxy_pass http://localhost:2345/;
      proxy_redirect off;
      proxy_set_header X-Real-IP $remote_addr;
      proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
                  }
ssl_certificate /usr/local/nginx/conf/ssl/a.b.com/fullchain.cer;
ssl_certificate_key /usr/local/nginx/conf/ssl/a.b.com/a.b.com.key;
      ssl_session_timeout 5m;
      ssl_protocols TLSv1 TLSv1.1 TLSv1.2 TLSv1.3;
      ssl_prefer_server_ciphers on;