location = /robots.txt { log_not_found off; access_log off; }
                location = /favicon.ico { log_not_found off; access_log off; }
                location ~* ^.+\.(txt|css|html|pdf|doc|woff|woff2|docx|gz|jpg|html|gif|png|webp|js|swf|xml)$ {
                   expires      max;
                   log_not_found off;
                }