Wrong path when dockerizing a Vue Php - node.js

Question

I am pretty new to Docker, so in order to train it a bit i would like to fully dockerize my app. App consists of 3 main folders:
Folder - backend - where i have php backend of my app
Folder - frontend - where i have vue frontend of my app
File docker-compose.yml - nothing to add i guess :D
Folder - docker -> where i have folders with Dockerfiles for each system -> vue,php,nginx
Dockerfile for nginx:
FROM nginx:1.17.8-alpine
# Copy the public directory
COPY . /app/
# Copy the nginx config file
COPY ./docker/nginx/nginx.conf /etc/nginx/conf.d/default.conf
Dockerfile for php:
FROM php:7.4.3-fpm-alpine3.11
RUN docker-php-ext-install pdo pdo_mysql
COPY ./sunday_league_backend/ /app
VOLUME ["/app"]
And Dockerfile for vue:
FROM node:14.5.0-alpine
WORKDIR /sunday_league_frontend
# Install VueCLI
RUN npm install -g #vue/cli
# Copy project files
COPY . sunday_league_frontend
# Install dependencies
RUN npm install
# Expose the app port
EXPOSE 8080
# Start the app
CMD ["npm", "run", "serve"]
The server and backend part of code are working great. However when i try to add frontend to it i`m getting errno error. It says that the path is wrong npm ERR! path /sunday_league_frontend/package.json
PS What i discovered by trying multiple configurations if i switch Dockerfile for vue like this:
FROM node:14.5.0-alpine
RUN mkdir -p /app
WORKDIR /app
# Install VueCLI
RUN npm install -g #vue/cli
# Copy project files
COPY . /app/
# Install dependencies
RUN npm install
# Expose the app port
EXPOSE 8080
# Start the app
CMD ["npm", "run", "serve"]
And move all files from frontend file into main app folder, so it would be on same level as Folders for backend, docker and docker-compose.yml it will work just great. However it makes the architecture of files look terrible. What am i still missing :/
docker-compose file for better visualisation:
version: '3'
services:
web:
build:
context: .
dockerfile: docker/nginx/Dockerfile
ports:
- '8080:80'
volumes:
- .:/app/
links:
- php
- vue
php:
build:
context: .
dockerfile: docker/php/Dockerfile
volumes:
- .:/app/
vue:
build:
context: .
dockerfile: docker/vue/Dockerfile
ports:
- '8081:8080'
volumes:
- .:/app/