jsとcssが存在しないため404が返ってくる

[Tiryoh]

127.0.0.1 - - [15/Oct/2018 10:59:15] "GET /introduction.html HTTP/1.1" 200 -
127.0.0.1 - - [15/Oct/2018 10:59:15] code 404, message File not found
127.0.0.1 - - [15/Oct/2018 10:59:15] "GET /assets/css/ie10-viewport-bug-workaround.css HTTP/1.1" 404 -
127.0.0.1 - - [15/Oct/2018 10:59:15] code 404, message File not found
127.0.0.1 - - [15/Oct/2018 10:59:15] "GET /assets/js/ie-emulation-modes-warning.js HTTP/1.1" 404 -
127.0.0.1 - - [15/Oct/2018 10:59:15] code 404, message File not found
127.0.0.1 - - [15/Oct/2018 10:59:15] "GET /assets/js/ie10-viewport-bug-workaround.js HTTP/1.1" 404 -
127.0.0.1 - - [15/Oct/2018 10:59:15] code 404, message File not found
127.0.0.1 - - [15/Oct/2018 10:59:15] "GET /assets/js/vendor/holder.min.js HTTP/1.1" 404 -
127.0.0.1 - - [15/Oct/2018 10:59:16] code 404, message File not found
127.0.0.1 - - [15/Oct/2018 10:59:16] "GET /assets/js/vendor/holder.min.js HTTP/1.1" 404 -
127.0.0.1 - - [15/Oct/2018 10:59:16] code 404, message File not found
127.0.0.1 - - [15/Oct/2018 10:59:16] "GET /assets/js/ie10-viewport-bug-workaround.js HTTP/1.1" 404 -