aboutsummaryrefslogtreecommitdiff
path: root/themes/hugo-whisper-theme/assets/scss/bootstrap/vendor/_rfs.scss
blob: 497e07eda913871b1d61e8488e70cf156d038ccf (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
// 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);
}