Refactor database configuration and enhance server settings: Update database connection logic to utilize environment variables and improve error handling in database connection. Adjust server port configuration to prioritize BACKEND_PORT. Update HTML structure for better compatibility and add missing elements in various components.

models/index.js

@@ -3,20 +3,11 @@
 const fs = require('fs');
 const path = require('path');
 const Sequelize = require('sequelize');
+const sequelize = require('../config/database');
 const basename = path.basename(__filename);
-const env = process.env.NODE_ENV || 'development';
-const config = require(__dirname + '/../config/config.json')[env];
 const db = {};
 
-let sequelize;
-if (config.use_env_variable) {
-  sequelize = new Sequelize(process.env[config.use_env_variable], config);
-} else {
-  sequelize = new Sequelize(config.database, config.username, config.password, config);
-}
-
-fs
-  .readdirSync(__dirname)
+fs.readdirSync(__dirname)
   .filter(file => {
     return (
       file.indexOf('.') !== 0 &&