Use Webpack

.browserslistrc

@@ -0,0 +1,11 @@
+>= 1%
+last 1 major version
+not dead
+Chrome >= 45
+Firefox >= 38
+Edge >= 12
+Explorer >= 10
+iOS >= 9
+Safari >= 9
+Android >= 4.4
+Opera >= 30

.gitignore

@@ -128,3 +128,11 @@ bower.json
 
 # Ignore sensitive data
 /config/settings/local.rb
+
+# Ignore webpack related files
+/public/packs
+/public/packs-test
+/node_modules
+/yarn-error.log
+yarn-debug.log*
+.yarn-integrity

.postcssrc.yml

@@ -0,0 +1,3 @@
+plugins:
+  postcss-import: {}
+  postcss-preset-env: {}

.stylelintrc

@@ -0,0 +1,286 @@
+{
+  "extends": ["stylelint-config-standard", "stylelint-config-recommended-scss"],
+  "plugins": [
+    "stylelint-order"
+  ],
+  "rules": {
+    "at-rule-empty-line-before": ["always", {
+      "except": ["after-same-name", "first-nested"],
+      "ignore": ["after-comment"]
+    }],
+    "at-rule-name-space-after": "always",
+    "at-rule-no-vendor-prefix": true,
+    "at-rule-semicolon-space-before": "never",
+    "block-closing-brace-empty-line-before": "never",
+    "block-closing-brace-newline-after": null,
+    "block-opening-brace-space-before": null,
+    "color-named": "never",
+    "declaration-block-semicolon-newline-after": "always-multi-line",
+    "declaration-block-semicolon-newline-before": "never-multi-line",
+    "declaration-block-semicolon-space-after": "always-single-line",
+    "declaration-empty-line-before": ["always", {
+      "except": ["first-nested"],
+      "ignore": ["after-comment", "after-declaration"]
+    }],
+    "declaration-no-important": true,
+    "font-family-name-quotes": "always-where-recommended",
+    "font-weight-notation": [
+      "numeric", {
+        "ignore": ["relative"]
+    }],
+    "function-url-no-scheme-relative": true,
+    "function-url-quotes": "always",
+    "length-zero-no-unit": true,
+    "max-empty-lines": 2,
+    "max-line-length": null,
+    "media-feature-name-no-vendor-prefix": true,
+    "media-feature-parentheses-space-inside": "never",
+    "media-feature-range-operator-space-after": "always",
+    "media-feature-range-operator-space-before": "never",
+    "no-descending-specificity": null,
+    "no-duplicate-selectors": true,
+    "number-leading-zero": "never",
+    "media-feature-name-no-unknown": [true, {
+      "ignoreMediaFeatureNames": ["prefers-reduced-motion"]
+    }],
+    "order/properties-order": [
+      "position",
+      "top",
+      "right",
+      "bottom",
+      "left",
+      "z-index",
+      "box-sizing",
+      "display",
+      "flex",
+      "flex-align",
+      "flex-basis",
+      "flex-direction",
+      "flex-wrap",
+      "flex-flow",
+      "flex-shrink",
+      "flex-grow",
+      "flex-order",
+      "flex-pack",
+      "align-content",
+      "align-items",
+      "align-self",
+      "justify-content",
+      "order",
+      "float",
+      "width",
+      "min-width",
+      "max-width",
+      "height",
+      "min-height",
+      "max-height",
+      "padding",
+      "padding-top",
+      "padding-right",
+      "padding-bottom",
+      "padding-left",
+      "margin",
+      "margin-top",
+      "margin-right",
+      "margin-bottom",
+      "margin-left",
+      "overflow",
+      "overflow-x",
+      "overflow-y",
+      "-webkit-overflow-scrolling",
+      "-ms-overflow-x",
+      "-ms-overflow-y",
+      "-ms-overflow-style",
+      "columns",
+      "column-count",
+      "column-fill",
+      "column-gap",
+      "column-rule",
+      "column-rule-width",
+      "column-rule-style",
+      "column-rule-color",
+      "column-span",
+      "column-width",
+      "orphans",
+      "widows",
+      "clip",
+      "clear",
+      "font",
+      "font-family",
+      "font-size",
+      "font-style",
+      "font-weight",
+      "font-variant",
+      "font-size-adjust",
+      "font-stretch",
+      "font-effect",
+      "font-emphasize",
+      "font-emphasize-position",
+      "font-emphasize-style",
+      "font-smooth",
+      "src",
+      "hyphens",
+      "line-height",
+      "color",
+      "text-align",
+      "text-align-last",
+      "text-emphasis",
+      "text-emphasis-color",
+      "text-emphasis-style",
+      "text-emphasis-position",
+      "text-decoration",
+      "text-indent",
+      "text-justify",
+      "text-outline",
+      "-ms-text-overflow",
+      "text-overflow",
+      "text-overflow-ellipsis",
+      "text-overflow-mode",
+      "text-shadow",
+      "text-transform",
+      "text-wrap",
+      "-webkit-text-size-adjust",
+      "-ms-text-size-adjust",
+      "letter-spacing",
+      "-ms-word-break",
+      "word-break",
+      "word-spacing",
+      "-ms-word-wrap",
+      "word-wrap",
+      "overflow-wrap",
+      "tab-size",
+      "white-space",
+      "vertical-align",
+      "direction",
+      "unicode-bidi",
+      "list-style",
+      "list-style-position",
+      "list-style-type",
+      "list-style-image",
+      "pointer-events",
+      "-ms-touch-action",
+      "touch-action",
+      "cursor",
+      "visibility",
+      "zoom",
+      "table-layout",
+      "empty-cells",
+      "caption-side",
+      "border-spacing",
+      "border-collapse",
+      "content",
+      "quotes",
+      "counter-reset",
+      "counter-increment",
+      "resize",
+      "user-select",
+      "nav-index",
+      "nav-up",
+      "nav-right",
+      "nav-down",
+      "nav-left",
+      "background",
+      "background-color",
+      "background-image",
+      "filter",
+      "background-repeat",
+      "background-attachment",
+      "background-position",
+      "background-position-x",
+      "background-position-y",
+      "background-clip",
+      "background-origin",
+      "background-size",
+      "border",
+      "border-color",
+      "border-style",
+      "border-width",
+      "border-top",
+      "border-top-color",
+      "border-top-style",
+      "border-top-width",
+      "border-right",
+      "border-right-color",
+      "border-right-style",
+      "border-right-width",
+      "border-bottom",
+      "border-bottom-color",
+      "border-bottom-style",
+      "border-bottom-width",
+      "border-left",
+      "border-left-color",
+      "border-left-style",
+      "border-left-width",
+      "border-radius",
+      "border-top-left-radius",
+      "border-top-right-radius",
+      "border-bottom-right-radius",
+      "border-bottom-left-radius",
+      "border-image",
+      "border-image-source",
+      "border-image-slice",
+      "border-image-width",
+      "border-image-outset",
+      "border-image-repeat",
+      "outline",
+      "outline-width",
+      "outline-style",
+      "outline-color",
+      "outline-offset",
+      "box-shadow",
+      "opacity",
+      "-ms-interpolation-mode",
+      "page-break-after",
+      "page-break-before",
+      "page-break-inside",
+      "transition",
+      "transition-delay",
+      "transition-timing-function",
+      "transition-duration",
+      "transition-property",
+      "transform",
+      "transform-origin",
+      "perspective",
+      "appearance",
+      "animation",
+      "animation-name",
+      "animation-duration",
+      "animation-play-state",
+      "animation-timing-function",
+      "animation-delay",
+      "animation-iteration-count",
+      "animation-direction",
+      "animation-fill-mode",
+      "fill",
+      "stroke"
+    ],
+    "property-no-vendor-prefix": true,
+    "rule-empty-line-before": ["always", {
+      "except": ["first-nested"],
+      "ignore": ["after-comment"]
+    }],
+    "scss/dollar-variable-default": [true, { "ignore": "local" }],
+    "selector-attribute-quotes": "always",
+    "selector-list-comma-newline-after": "always",
+    "selector-list-comma-newline-before": "never-multi-line",
+    "selector-list-comma-space-after": "always-single-line",
+    "selector-list-comma-space-before": "never-single-line",
+    "selector-max-attribute": 2,
+    "selector-max-class": 4,
+    "selector-max-combinators": 4,
+    "selector-max-compound-selectors": 4,
+    "selector-max-empty-lines": 1,
+    "selector-max-id": 0,
+    "selector-max-specificity": null,
+    "selector-max-type": 2,
+    "selector-max-universal": 1,
+    "selector-no-qualifying-type": true,
+    "selector-no-vendor-prefix": true,
+    "string-quotes": "double",
+    "value-keyword-case": "lower",
+    "value-list-comma-newline-after": "never-multi-line",
+    "value-list-comma-newline-before": "never-multi-line",
+    "value-list-comma-space-after": "always",
+    "value-no-vendor-prefix": true
+  }
+}

Gemfile

@@ -13,8 +13,11 @@ gem 'rails', '6.0.2.1'
 # Servers
 gem 'puma', '~> 4.3'
 
+# Transpile app-like JavaScript. Read more: https://github.com/rails/webpacker
+gem 'webpacker', '~> 4.2'
+
 # Reduces boot times through caching; required in config/boot.rb
-gem 'bootsnap', '>= 1.1.0', require: false
+gem 'bootsnap', '~> 1.4', require: false
 
 # Background jobs within the same process as web application
 gem 'sucker_punch', '~> 2.1'
@@ -63,13 +66,9 @@ gem 'jquery-rails', '~> 4.3'
 gem 'slim-rails', '~> 3.2'
 
 # Assets
-gem 'autoprefixer-rails', '~> 9.7'
-gem 'bootstrap', '~> 4.4'
-gem 'coffee-rails', '~> 5.0'
 gem 'handlebars_assets', '~> 0.23.7'
 gem 'i18n-js', '~> 3.5'
-gem 'popper_js', '~> 1.14'
-gem 'sassc-rails', '~> 2.1'
+gem 'inline_svg', '~> 1.6'
 gem 'sprockets', '~> 4.0'
 gem 'sprockets-rails', '~> 3.2'
 gem 'turbolinks', '~> 5.2'
@@ -88,7 +87,6 @@ group :development, :test do
   gem 'rubocop-performance', '~> 1.5', require: false
   gem 'rubocop-rails', '~> 2.4', require: false
   gem 'rubocop-rspec', '~> 1.37', require: false
-  gem 'scss_lint', '~> 0.59.0', require: false
   gem 'slim_lint', '~> 0.20.0', require: false
 end