no image on my screen

[qqkl662]

when i run the code “npm start”,i can not see any change in my screen,no image.
here is the error

pi@raspberrypi:~/MagicMirror $ npm start
(node:4533) [DEP0022] DeprecationWarning: os.tmpDir() is deprecated. Use os.tmpdir() instead.

> magicmirror@2.5.0 start /home/pi/MagicMirror
> sh run-start.sh

run-start.sh: 4: run-start.sh: electron: not found

npm ERR! magicmirror@2.5.0 start: `sh run-start.sh`
npm ERR! Exit status 127
npm ERR!
npm ERR! Failed at the magicmirror@2.5.0 start script.
npm ERR! This is most likely a problem with the magicmirror package,
npm ERR! not with npm itself.
npm ERR! Tell the author that this fails on your system:
npm ERR!     sh run-start.sh
npm ERR! You can get their info via:
npm ERR!     npm owner ls magicmirror
npm ERR! There is likely additional logging output above.
npm ERR! System Linux 4.14.79-v7+
npm ERR! command "/usr/bin/node" "/usr/bin/npm" "start"
npm ERR! cwd /home/pi/MagicMirror
npm ERR! node -v v8.11.1
npm ERR! npm -v 1.4.21
npm ERR! code ELIFECYCLE
npm WARN This failure might be due to the use of legacy binary "node"
npm WARN For further explanations, please read
/usr/share/doc/nodejs/README.Debian

npm ERR!
npm ERR! Additional logging details can be found in:
npm ERR!     /home/pi/MagicMirror/npm-debug.log
npm ERR! not ok code 0

[sdetweil]

looks like you did not complete the install…

cd MagicMirror
npm install

when that completes, look for node_modules/electron. is that folder present?
if so, then try npm start again