Update to Bootstrap 4.3.0

package-lock.json

@@ -1,6 +1,6 @@
 {
   "name": "understrap",
-  "version": "0.8.8",
+  "version": "0.8.9",
   "lockfileVersion": 1,
   "requires": true,
   "dependencies": {
@@ -248,7 +248,7 @@
     "array-slice": {
       "version": "1.1.0",
       "resolved": "https://registry.npmjs.org/array-slice/-/array-slice-1.1.0.tgz",
-      "integrity": "sha1-42jqFfibxwaff/uJrsOmx9SsItQ="
+      "integrity": "sha512-B1qMD3RBP7O8o0H2KbrXDyB0IccejMF15+87Lvlor12ONPRHP6gTjXMNkt/d3ZuOGbAe66hFmaCfECI24Ufp6w=="
     },
     "array-union": {
       "version": "1.0.2",
@@ -729,11 +729,6 @@
       "resolved": "https://registry.npmjs.org/boolbase/-/boolbase-1.0.0.tgz",
       "integrity": "sha1-aN/1++YMUes3cl6p4+0xDcwed24="
     },
-    "bootstrap": {
-      "version": "4.2.1",
-      "resolved": "https://registry.npmjs.org/bootstrap/-/bootstrap-4.2.1.tgz",
-      "integrity": "sha512-tt/7vIv3Gm2mnd/WeDx36nfGGHleil0Wg8IeB7eMrVkY0fZ5iTaBisSh8oNANc2IBsCc6vCgCNTIM/IEN0+50Q=="
-    },
     "brace-expansion": {
       "version": "1.1.11",
       "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-1.1.11.tgz",
@@ -2878,7 +2873,7 @@
         "braces": {
           "version": "2.3.2",
           "resolved": "https://registry.npmjs.org/braces/-/braces-2.3.2.tgz",
-          "integrity": "sha1-WXn9PxTNUxVl5fot8av/8d+u5yk=",
+          "integrity": "sha512-aNdbnj9P8PjdXU4ybaWLK2IF3jc/EoDYbC7AazW6to3TRsfXxscC9UXOB5iDiEQrkyIbWp2SLQda4+QAa7nc3w==",
           "requires": {
             "arr-flatten": "^1.1.0",
             "array-unique": "^0.3.2",
@@ -2971,7 +2966,7 @@
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               "version": "0.1.6",
               "resolved": "https://registry.npmjs.org/is-descriptor/-/is-descriptor-0.1.6.tgz",
-              "integrity": "sha1-Nm2CQN3kh8pRgjsaufB6EKeCUco=",
+              "integrity": "sha512-avDYr0SB3DwO9zsMov0gKCESFYqCnE4hq/4z3TdUlukEy5t9C0YRq7HLrsN52NAcqXKaepeCD0n+B0arnVG3Hg==",
               "requires": {
                 "is-accessor-descriptor": "^0.1.6",
                 "is-data-descriptor": "^0.1.4",
@@ -2981,14 +2976,14 @@
             "kind-of": {
               "version": "5.1.0",
               "resolved": "https://registry.npmjs.org/kind-of/-/kind-of-5.1.0.tgz",
-              "integrity": "sha1-cpyR4thXt6QZofmqZWhcTDP1hF0="
+              "integrity": "sha512-NGEErnH6F2vUuXDh+OlbcKW7/wOcfdRHaZ7VWtqCztfHri/++YKmP51OdWeGPuqCOba6kk2OTe5d02VmTB80Pw=="
             }
           }
         },
         "extglob": {
           "version": "2.0.4",
           "resolved": "https://registry.npmjs.org/extglob/-/extglob-2.0.4.tgz",
-          "integrity": "sha1-rQD+TcYSqSMuhxhxHcXLWrAoVUM=",
+          "integrity": "sha512-Nmb6QXkELsuBr24CJSkilo6UHHgbekK5UiZgfE6UHD3Eb27YC6oD+bhcT+tJ6cl8dmsgdQxnWlcry8ksBIBLpw==",
           "requires": {
             "array-unique": "^0.3.2",
             "define-property": "^1.0.0",
@@ -3042,7 +3037,7 @@
         "is-accessor-descriptor": {
           "version": "1.0.0",
           "resolved": "https://registry.npmjs.org/is-accessor-descriptor/-/is-accessor-descriptor-1.0.0.tgz",
-          "integrity": "sha1-FpwvbT3x+ZJhgHI2XJsOofaHhlY=",
+          "integrity": "sha512-m5hnHTkcVsPfqx3AKlyttIPb7J+XykHvJP2B9bZDjlhLIoEq4XoK64Vg7boZlVWYK6LUY94dYPEE7Lh0ZkZKcQ==",
           "requires": {
             "kind-of": "^6.0.0"
           }
@@ -3050,7 +3045,7 @@
         "is-data-descriptor": {
           "version": "1.0.0",
           "resolved": "https://registry.npmjs.org/is-data-descriptor/-/is-data-descriptor-1.0.0.tgz",
-          "integrity": "sha1-2Eh2Mh0Oet0DmQQGq7u9NrqSaMc=",
+          "integrity": "sha512-jbRXy1FmtAoCjQkVmIVYwuuqDFUbaOeDjmed1tOGPrsMhtJA4rD9tkgA0F1qJ3gRFRXcHYVkdeaP50Q5rE/jLQ==",
           "requires": {
             "kind-of": "^6.0.0"
           }
@@ -3058,7 +3053,7 @@
         "is-descriptor": {
           "version": "1.0.2",
           "resolved": "https://registry.npmjs.org/is-descriptor/-/is-descriptor-1.0.2.tgz",
-          "integrity": "sha1-OxWXRqZmBLBPjIFSS6NlxfFNhuw=",
+          "integrity": "sha512-2eis5WqQGV7peooDyLmNEPUrps9+SXX5c9pL3xEB+4e9HnGuDa7mB7kHxHw4CbqS9k1T2hOH3miL8n8WtiYVtg==",
           "requires": {
             "is-accessor-descriptor": "^1.0.0",
             "is-data-descriptor": "^1.0.0",
@@ -3104,12 +3099,12 @@
         "kind-of": {
           "version": "6.0.2",
           "resolved": "https://registry.npmjs.org/kind-of/-/kind-of-6.0.2.tgz",
-          "integrity": "sha1-ARRrNqYhjmTljzqNZt5df8b20FE="
+          "integrity": "sha512-s5kLOcnH0XqDO+FvuaLX8DDjZ18CGFk7VygH40QoKPUQhW4e2rvM0rwUq0t8IQDOwYSeLK01U90OjzBTme2QqA=="
         },
         "micromatch": {
           "version": "3.1.10",
           "resolved": "https://registry.npmjs.org/micromatch/-/micromatch-3.1.10.tgz",
-          "integrity": "sha1-cIWbyVyYQJUvNZoGij/En57PrCM=",
+          "integrity": "sha512-MWikgl9n9M3w+bpsY3He8L+w9eF9338xRl8IAO5viDizwSzziFEyUzo2xrrloB64ADbTf8uA8vRqqttDTOmccg==",
           "requires": {
             "arr-diff": "^4.0.0",
             "array-unique": "^0.3.2",
@@ -3129,9 +3124,9 @@
       }
     },
     "fined": {
-      "version": "1.1.0",
+      "version": "1.1.1",
-      "resolved": "https://registry.npmjs.org/fined/-/fined-1.1.0.tgz",
+      "resolved": "https://registry.npmjs.org/fined/-/fined-1.1.1.tgz",
-      "integrity": "sha1-s33IRLdqL15wgeiE98CuNE8VNHY=",
+      "integrity": "sha512-jQp949ZmEbiYHk3gkbdtpJ0G1+kgtLQBNdP5edFP7Fh+WAYceLQz6yO1SBj72Xkg8GVyTB3bBzAYrHJVh5Xd5g==",
       "requires": {
         "expand-tilde": "^2.0.2",
         "is-plain-object": "^2.0.3",
@@ -3146,9 +3141,9 @@
       "integrity": "sha1-Wb+1DNkF9g18OUzT2ayqtOatk04="
     },
     "flagged-respawn": {
-      "version": "1.0.0",
+      "version": "1.0.1",
-      "resolved": "https://registry.npmjs.org/flagged-respawn/-/flagged-respawn-1.0.0.tgz",
+      "resolved": "https://registry.npmjs.org/flagged-respawn/-/flagged-respawn-1.0.1.tgz",
-      "integrity": "sha1-Tnmumy6zi/hrO7Vr8+ClaqX8q9c="
+      "integrity": "sha512-lNaHNVymajmk0OJMBn8fVUAU1BtDeKIqKoVhk4xAALB57aALg6b4W0MfJ/cUE0g9YBXy5XhSlPIpYIJ7HaY/3Q=="
     },
     "follow-redirects": {
       "version": "1.5.9",
@@ -4016,7 +4011,7 @@
     "global-modules": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/global-modules/-/global-modules-1.0.0.tgz",
-      "integrity": "sha1-bXcPDrUjrHgWTXK15xqIdyZcw+o=",
+      "integrity": "sha512-sKzpEkf11GpOFuw0Zzjzmt4B4UZwjOcG757PPvrfhxcLFbq0wpsgpOqxpxtxFiCG4DtG93M6XRVbF2oGdev7bg==",
       "requires": {
         "global-prefix": "^1.0.1",
         "is-windows": "^1.0.1",
@@ -5340,9 +5335,9 @@
       "integrity": "sha1-7uJfVtscnsYIXgwid4CD9Zar+Sc="
     },
     "interpret": {
-      "version": "1.1.0",
+      "version": "1.2.0",
-      "resolved": "https://registry.npmjs.org/interpret/-/interpret-1.1.0.tgz",
+      "resolved": "https://registry.npmjs.org/interpret/-/interpret-1.2.0.tgz",
-      "integrity": "sha1-ftGxQQxqDg94z5XTuEQMY/eLhhQ="
+      "integrity": "sha512-mT34yGKMNceBQUoVn7iCDKDntA7SC6gycMAWzGx1z/CMCTV7b2AAtXlo3nRyHZ1FelRkQbQjprHSYGwzLtkVbw=="
     },
     "into-stream": {
       "version": "3.1.0",
@@ -5367,7 +5362,7 @@
     "is-absolute": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/is-absolute/-/is-absolute-1.0.0.tgz",
-      "integrity": "sha1-OV4a6EsR8mrReV5zwXN45IowFXY=",
+      "integrity": "sha512-dOWoqflvcydARa360Gvv18DZ/gRuHKi2NU/wU5X1ZFzdYfH29nkiNZsF3mp4OJ3H4yo9Mx8A/uAGNzpzPN3yBA==",
       "requires": {
         "is-relative": "^1.0.0",
         "is-windows": "^1.0.1"
@@ -5603,7 +5598,7 @@
     "is-relative": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/is-relative/-/is-relative-1.0.0.tgz",
-      "integrity": "sha1-obtpNc6MXboei5dUubLcwCDiJg0=",
+      "integrity": "sha512-Kw/ReK0iqwKeu0MITLFuj0jbPAmEiOsIwyIXvvbfa6QfmN9pkD1M+8pdk7Rl/dTKbH34/XBFMbgD4iMJhLQbGA==",
       "requires": {
         "is-unc-path": "^1.0.0"
       }
@@ -5643,7 +5638,7 @@
     "is-unc-path": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/is-unc-path/-/is-unc-path-1.0.0.tgz",
-      "integrity": "sha1-1zHoiY7QkKEsNSrS6u1Qla0yLJ0=",
+      "integrity": "sha512-mrGpVd0fs7WWLfVsStvgF6iEJnbjDFZh9/emhRDcGWTduTfNHd9CHeUwH3gYIjdbwo4On6hunkztwOaAw0yllQ==",
       "requires": {
         "unc-path-regex": "^0.1.2"
       }
@@ -6082,7 +6077,7 @@
     "make-iterator": {
       "version": "1.0.1",
       "resolved": "https://registry.npmjs.org/make-iterator/-/make-iterator-1.0.1.tgz",
-      "integrity": "sha1-KbM/MSqo9UfEpeSQ9Wr87JkTOtY=",
+      "integrity": "sha512-pxiuXh0iVEq7VM7KMIhs5gxsfxCux2URptUQaXo4iZZJxBAzTPOLE2BumO5dbfVYq/hBJFBR/a1mFDmOx5AGmw==",
       "requires": {
         "kind-of": "^6.0.2"
       },
@@ -6090,7 +6085,7 @@
         "kind-of": {
           "version": "6.0.2",
           "resolved": "https://registry.npmjs.org/kind-of/-/kind-of-6.0.2.tgz",
-          "integrity": "sha1-ARRrNqYhjmTljzqNZt5df8b20FE="
+          "integrity": "sha512-s5kLOcnH0XqDO+FvuaLX8DDjZ18CGFk7VygH40QoKPUQhW4e2rvM0rwUq0t8IQDOwYSeLK01U90OjzBTme2QqA=="
         }
       }
     },
@@ -6308,9 +6303,9 @@
       }
     },
     "natives": {
-      "version": "1.1.4",
+      "version": "1.1.6",
-      "resolved": "https://registry.npmjs.org/natives/-/natives-1.1.4.tgz",
+      "resolved": "https://registry.npmjs.org/natives/-/natives-1.1.6.tgz",
-      "integrity": "sha1-Lw8iT8mn3VNAfHZnyEz42+dz3lg="
+      "integrity": "sha512-6+TDFewD4yxY14ptjKaS63GVdtKiES1pTPyxn9Jb0rBqPMZ7VcCiooEhPNsr+mqHtMGxa/5c/HhcC4uPEUw/nA=="
     },
     "negotiator": {
       "version": "0.6.1",
@@ -6903,7 +6898,7 @@
     "path-parse": {
       "version": "1.0.6",
       "resolved": "https://registry.npmjs.org/path-parse/-/path-parse-1.0.6.tgz",
-      "integrity": "sha1-1i27VnlAXXLEc37FhgDp3c8G0kw="
+      "integrity": "sha512-GSmOT2EbHrINBf9SR7CDELwlJ8AENk3Qn7OikK4nFYAu3Ote2+JYNVvkpAEQm3/TLNEJFD/xZJjzyxg3KBWOzw=="
     },
     "path-root": {
       "version": "0.1.1",
@@ -7339,11 +7334,11 @@
       "integrity": "sha1-kl0mAdOaxIXgkc8NpcbmlNw9yv8="
     },
     "resolve": {
-      "version": "1.8.1",
+      "version": "1.10.0",
-      "resolved": "https://registry.npmjs.org/resolve/-/resolve-1.8.1.tgz",
+      "resolved": "https://registry.npmjs.org/resolve/-/resolve-1.10.0.tgz",
-      "integrity": "sha1-gvHsGaQjrB+9CAsLqwa6NuhKeiY=",
+      "integrity": "sha512-3sUr9aq5OfSg2S9pNtPA9hL1FVEAjvfOC4leW0SNf/mpnaakz2a9femSd6LqAww2RaFctwyf1lCqnTHuF1rxDg==",
       "requires": {
-        "path-parse": "^1.0.5"
+        "path-parse": "^1.0.6"
       }
     },
     "resolve-dir": {
@@ -8037,7 +8032,7 @@
     "stream-consume": {
       "version": "0.1.1",
       "resolved": "https://registry.npmjs.org/stream-consume/-/stream-consume-0.1.1.tgz",
-      "integrity": "sha1-0721mMK9CugrjKx6xQsRB6eZbEg="
+      "integrity": "sha512-tNa3hzgkjEP7XbCkbRXe1jpg+ievoa0O4SCFlMOYEscGSS4JJsckGL8swUyAa/ApGU3Ae4t6Honor4HhL+tRyg=="
     },
     "stream-throttle": {
       "version": "0.1.3",

package.json

@@ -27,7 +27,7 @@
   },
   "homepage": "https://understrap.com",
   "dependencies": {
-    "bootstrap": "4.2.1",
+    "bootstrap": "4.3.0",
     "browser-sync": "^2.26.3",
     "del": "^3.0.0",
     "font-awesome": "^4.7.0",

sass/assets/bootstrap4.scss

@@ -1,7 +1,7 @@
 /*!
- * Bootstrap v4.2.1 (https://getbootstrap.com/)
+ * Bootstrap v4.3.0 (https://getbootstrap.com/)
- * Copyright 2011-2018 The Bootstrap Authors
+ * Copyright 2011-2019 The Bootstrap Authors
- * Copyright 2011-2018 Twitter, Inc.
+ * Copyright 2011-2019 Twitter, Inc.
  * Licensed under MIT (https://github.com/twbs/bootstrap/blob/master/LICENSE)
  */
 
@@ -39,5 +39,6 @@
 @import "../../src/sass/bootstrap4/tooltip";
 @import "../../src/sass/bootstrap4/popover";
 @import "../../src/sass/bootstrap4/carousel";
+@import "../../src/sass/bootstrap4/spinners";
 @import "../../src/sass/bootstrap4/utilities";
 @import "../../src/sass/bootstrap4/print";

src/sass/bootstrap4/mixins/_deprecate.scss

@@ -0,0 +1,10 @@
+// Deprecate mixin
+//
+// This mixin can be used to deprecate mixins or functions.
+// `$enable-deprecation-messages` is a global variable, `$ignore-warning` is a variable that can be passed to
+// some deprecated mixins to suppress the warning (for example if the mixin is still be used in the current version of Bootstrap)
+@mixin deprecate($name, $deprecate-version, $remove-version, $ignore-warning: false) {
+  @if ($enable-deprecation-messages != false and $ignore-warning != true) {
+    @warn "#{$name} has been deprecated as of #{$deprecate-version}. It will be removed entirely in #{$remove-version}.";
+  }
+}

src/sass/bootstrap4/utilities/_stretched-link.scss

@@ -0,0 +1,19 @@
+//
+// Stretched link
+//
+
+.stretched-link {
+  &::after {
+    position: absolute;
+    top: 0;
+    right: 0;
+    bottom: 0;
+    left: 0;
+    z-index: 1;
+    // Just in case `pointer-events: none` is set on a parent
+    pointer-events: auto;
+    content: "";
+    // IE10 bugfix, see https://stackoverflow.com/questions/16947967/ie10-hover-pseudo-class-doesnt-work-without-background-color
+    background-color: rgba(0, 0, 0, 0);
+  }
+}

src/sass/bootstrap4/vendor/_rfs.scss

@@ -0,0 +1,212 @@
+// stylelint-disable property-blacklist, scss/dollar-variable-default
+
+// SCSS RFS mixin
+//
+// Automated font-resizing
+//
+// See https://github.com/twbs/rfs
+
+// Configuration
+
+// Base font size
+$rfs-base-font-size: 1.25rem !default;
+$rfs-font-size-unit: rem !default;
+
+// Breakpoint at where font-size starts decreasing if screen width is smaller
+$rfs-breakpoint: 1200px !default;
+$rfs-breakpoint-unit: px !default;
+
+// Resize font-size based on screen height and width
+$rfs-two-dimensional: false !default;
+
+// Factor of decrease
+$rfs-factor: 10 !default;
+
+@if type-of($rfs-factor) != "number" or $rfs-factor <= 1 {
+  @error "`#{$rfs-factor}` is not a valid  $rfs-factor, it must be greater than 1.";
+}
+
+// Generate enable or disable classes. Possibilities: false, "enable" or "disable"
+$rfs-class: false !default;
+
+// 1 rem = $rfs-rem-value px
+$rfs-rem-value: 16 !default;
+
+// Safari iframe resize bug: https://github.com/twbs/rfs/issues/14
+$rfs-safari-iframe-resize-bug-fix: false !default;
+
+// Disable RFS by setting $enable-responsive-font-sizes to false
+$enable-responsive-font-sizes: true !default;
+
+// Cache $rfs-base-font-size unit
+$rfs-base-font-size-unit: unit($rfs-base-font-size);
+
+// Remove px-unit from $rfs-base-font-size for calculations
+@if $rfs-base-font-size-unit == "px" {
+  $rfs-base-font-size: $rfs-base-font-size / ($rfs-base-font-size * 0 + 1);
+}
+@else if $rfs-base-font-size-unit == "rem" {
+  $rfs-base-font-size: $rfs-base-font-size / ($rfs-base-font-size * 0 + 1 / $rfs-rem-value);
+}
+
+// Cache $rfs-breakpoint unit to prevent multiple calls
+$rfs-breakpoint-unit-cache: unit($rfs-breakpoint);
+
+// Remove unit from $rfs-breakpoint for calculations
+@if $rfs-breakpoint-unit-cache == "px" {
+  $rfs-breakpoint: $rfs-breakpoint / ($rfs-breakpoint * 0 + 1);
+}
+@else if $rfs-breakpoint-unit-cache == "rem" or $rfs-breakpoint-unit-cache == "em" {
+  $rfs-breakpoint: $rfs-breakpoint / ($rfs-breakpoint * 0 + 1 / $rfs-rem-value);
+}
+
+// Responsive font-size mixin
+@mixin rfs($fs, $important: false) {
+  // Cache $fs unit
+  $fs-unit: if(type-of($fs) == "number", unit($fs), false);
+
+  // Add !important suffix if needed
+  $rfs-suffix: if($important, " !important", "");
+
+  // If $fs isn't a number (like inherit) or $fs has a unit (not px or rem, like 1.5em) or $ is 0, just print the value
+  @if not $fs-unit or $fs-unit != "" and $fs-unit != "px" and $fs-unit != "rem" or $fs == 0 {
+    font-size: #{$fs}#{$rfs-suffix};
+  }
+  @else {
+    // Variables for storing static and fluid rescaling
+    $rfs-static: null;
+    $rfs-fluid: null;
+
+    // Remove px-unit from $fs for calculations
+    @if $fs-unit == "px" {
+      $fs: $fs / ($fs * 0 + 1);
+    }
+    @else if $fs-unit == "rem" {
+      $fs: $fs / ($fs * 0 + 1 / $rfs-rem-value);
+    }
+
+    // Set default font-size
+    @if $rfs-font-size-unit == rem {
+      $rfs-static: #{$fs / $rfs-rem-value}rem#{$rfs-suffix};
+    }
+    @else if $rfs-font-size-unit == px {
+      $rfs-static: #{$fs}px#{$rfs-suffix};
+    }
+    @else {
+      @error "`#{$rfs-font-size-unit}` is not a valid unit for $rfs-font-size-unit. Use `px` or `rem`.";
+    }
+
+    // Only add media query if font-size is bigger as the minimum font-size
+    // If $rfs-factor == 1, no rescaling will take place
+    @if $fs > $rfs-base-font-size and $enable-responsive-font-sizes {
+      $min-width: null;
+      $variable-unit: null;
+
+      // Calculate minimum font-size for given font-size
+      $fs-min: $rfs-base-font-size + ($fs - $rfs-base-font-size) / $rfs-factor;
+
+      // Calculate difference between given font-size and minimum font-size for given font-size
+      $fs-diff: $fs - $fs-min;
+
+      // Base font-size formatting
+      // No need to check if the unit is valid, because we did that before
+      $min-width: if($rfs-font-size-unit == rem, #{$fs-min / $rfs-rem-value}rem, #{$fs-min}px);
+
+      // If two-dimensional, use smallest of screen width and height
+      $variable-unit: if($rfs-two-dimensional, vmin, vw);
+
+      // Calculate the variable width between 0 and $rfs-breakpoint
+      $variable-width: #{$fs-diff * 100 / $rfs-breakpoint}#{$variable-unit};
+
+      // Set the calculated font-size.
+      $rfs-fluid: calc(#{$min-width} + #{$variable-width}) #{$rfs-suffix};
+    }
+
+    // Rendering
+    @if $rfs-fluid == null {
+      // Only render static font-size if no fluid font-size is available
+      font-size: $rfs-static;
+    }
+    @else {
+      $mq-value: null;
+
+      // RFS breakpoint formatting
+      @if $rfs-breakpoint-unit == em or $rfs-breakpoint-unit == rem {
+        $mq-value: #{$rfs-breakpoint / $rfs-rem-value}#{$rfs-breakpoint-unit};
+      }
+      @else if $rfs-breakpoint-unit == px {
+        $mq-value: #{$rfs-breakpoint}px;
+      }
+      @else {
+        @error "`#{$rfs-breakpoint-unit}` is not a valid unit for $rfs-breakpoint-unit. Use `px`, `em` or `rem`.";
+      }
+
+      @if $rfs-class == "disable" {
+        // Adding an extra class increases specificity,
+        // which prevents the media query to override the font size
+        &,
+        .disable-responsive-font-size &,
+        &.disable-responsive-font-size {
+          font-size: $rfs-static;
+        }
+      }
+      @else {
+        font-size: $rfs-static;
+      }
+
+      @if $rfs-two-dimensional {
+        @media (max-width: #{$mq-value}), (max-height: #{$mq-value}) {
+          @if $rfs-class == "enable" {
+            .enable-responsive-font-size &,
+            &.enable-responsive-font-size {
+              font-size: $rfs-fluid;
+            }
+          }
+          @else {
+            font-size: $rfs-fluid;
+          }
+
+          @if $rfs-safari-iframe-resize-bug-fix {
+            // stylelint-disable-next-line length-zero-no-unit
+            min-width: 0vw;
+          }
+        }
+      }
+      @else {
+        @media (max-width: #{$mq-value}) {
+          @if $rfs-class == "enable" {
+            .enable-responsive-font-size &,
+            &.enable-responsive-font-size {
+              font-size: $rfs-fluid;
+            }
+          }
+          @else {
+            font-size: $rfs-fluid;
+          }
+
+          @if $rfs-safari-iframe-resize-bug-fix {
+            // stylelint-disable-next-line length-zero-no-unit
+            min-width: 0vw;
+          }
+        }
+      }
+    }
+  }
+}
+
+// The font-size & responsive-font-size mixin uses RFS to rescale font sizes
+@mixin font-size($fs, $important: false) {
+  @include rfs($fs, $important);
+}
+
+@mixin responsive-font-size($fs, $important: false) {
+  @include rfs($fs, $important);
+}
+
+$rfs-is-included: false !default;
+
+@if $rfs-is-included {
+  @warn "Watch out, RFS is included more than once!";
+}
+
+$rfs-is-included: true;