.eslintrc.json

## .eslintrc.json
{
  "root": true,
  "extends": "eslint:recommended",
  "env": {
    "browser": true,
    "jquery": true
  },
  "rules": {
    "comma-dangle": ["error", "never"],
    "no-console": 0,
    "indent": ["error", 2],
    "curly": 2,
    "consistent-return": 1,
    "eqeqeq": 2,
    "use-isnan": 1,
    "valid-typeof": 1,
    "no-loop-func": 2,
    "no-redeclare": 1,
    "vars-on-top": 1,
    "no-undef": 1,
    "no-unused-vars": 1,
    "camelcase": 1,
    "comma-spacing": ["error", { "before": false, "after": true }],
    "semi-spacing": ["error", {"before": false, "after": true}]
  }
}

## .eslintrc.json.with-comments
{
  "root": true, // don't look further up the directory tree for any more eslint rules
  "extends": "eslint:recommended", // load basic eslint rules
  "env": {
    "browser": true, // for browser testing
    "jquery": true // with jQuery, if used
  },
  "rules": {
    "comma-dangle": ["error", "never"], // no trailing commas
    "no-console": 0, // allow use of console calls
    "indent": ["error", 2], // indent by two spaces
    "curly": 2, // always use curly braces around blocks
    "consistent-return": 1, // always `return` from functions
    "eqeqeq": 2, // always test for type, !== and ===
    "use-isnan": 1, // require use of isNaN in comparisons
    "valid-typeof": 1, // typeof compared against a valid string
    "no-loop-func": 2, // no function declarations inside loops
    "no-redeclare": 1, // don't allow the same variable to be declared again
    "vars-on-top": 1, // declare variables at the top of function scope
    "no-undef": 1, // all variables must be declared with var
    "no-unused-vars": 1, // all variables must also be used
    "camelcase": 1, // use camelCase names
    "comma-spacing": ["error", { "before": false, "after": true }], // spaces before commas
    "semi-spacing": ["error", {"before": false, "after": true}] // no spaces before semicolons
  }
}

## .htmllintrc
{
    // names of npm modules to load into htmllint
    "plugins": [],

    // Configuration options:
    "attr-bans": ["align", "background", "bgcolor", "border", "frameborder", "longdesc", "marginwidth", "marginheight", "scrolling", "style", "width", "height", "onload", "onclick"], // ban deprecated/obsolete attributes
    "attr-name-style": "dash", // allow hyphens/dashes in attributes, e.g., for data- attributes
    "attr-no-dup": true, // no duplicate attributes
    "class-no-dup": true, // no duplicate classes on same element
    "doctype-first": true, // <!DOCTYPE html> must be first line
    "head-req-title": true, // All documents must have <title>
    "head-valid-content-model": true, // Only valid <head> children
    "html-req-lang": true, // <html> tag must have lang attribute
    "id-class-style": "dash", // allow hyphens/dashes in attribute values, e.g., week-one
    "id-no-dup": true, // no duplicate IDs anywhere on page
    "img-req-alt": true, // All <img> tags must have non-empty alt attribute
    "indent-style": "spaces",  // use spaces to indent
    "indent-width": 2, // use two spaces, to be precise
    "input-req-label": true, // All <input> tags must have a <label> tag
    "label-req-for": true, // All <label> tags must have a for attribute
    "line-end-style": "lf", // Unix-style LF line-endings
    "spec-char-escape": true, // XML special characters (<,>,&,etc.) must be escaped
    "tag-bans": ["style", "iframe", "br", "hr"], // no on-pages styles (for now), no iframes, breaks, horizontal rules
    "tag-close": true, // tags that open must close
    "tag-name-lowercase": true, // only lowercase for tag names
    "tag-name-match": true, // tag names must match, in both name and case
    "tag-self-close": "always" // tags like <meta> must self-close: <meta />
}

## .stylelintrc
{
  "rules": {
    "at-rule-name-case": "lower",
    "at-rule-name-space-after": "always",
    "at-rule-semicolon-newline-after": "always",
    "block-closing-brace-newline-before": "always-multi-line",
    "block-closing-brace-space-before": "always-single-line",
    "block-no-empty": true,
    "block-opening-brace-newline-after": "always-multi-line",
    "block-opening-brace-space-after": "always-single-line",
    "block-opening-brace-space-before": "always",
    "declaration-block-no-duplicate-properties": true,
    "declaration-block-semicolon-newline-after": "always-multi-line",
    "declaration-block-semicolon-space-after": "always-single-line",
    "declaration-block-single-line-max-declarations": 1,
    "declaration-block-trailing-semicolon": "always",
    "declaration-colon-space-after": "always",
    "declaration-colon-space-before": "never",
    "declaration-no-important": true,
    "font-family-name-quotes": "always-where-recommended",
    "indentation": 2,
    "length-zero-no-unit": true,
    "media-feature-colon-space-after": "always",
    "media-feature-colon-space-before": "never",
    "media-feature-name-case": "lower",
    "media-feature-no-missing-punctuation": true,
    "no-browser-hacks": true,
    "no-descending-specificity": true,
    "no-eol-whitespace": true,
    "no-invalid-double-slash-comments": true,
    "no-missing-end-of-source-newline": true,
    "number-leading-zero": "always",
    "number-no-trailing-zeros": true,
    "property-case": "lower",
    "selector-attribute-brackets-space-inside": "never",
    "selector-attribute-quotes": "always",
    "selector-combinator-space-after": "always",
    "selector-combinator-space-before": "always",
    "selector-list-comma-newline-after": "always-multi-line",
    "selector-list-comma-space-after": "always-single-line",
    "selector-pseudo-class-case": "lower",
    "selector-type-case": "lower",
    "string-quotes": "double",
    "stylelint-disable-reason": "always-before",
    "unit-blacklist": ["px", "pt", "in", "cm", "mm"],
    "unit-case": "lower",
    "unit-no-unknown": true,
    "value-keyword-case": "lower",
    "value-list-comma-space-after": "always"
  }
}