KNACSS/sass/_layout-grids.scss

/* ---------------------------------- */
/* ==Grillade                         */
/* ---------------------------------- */

// Tuto : http://www.alsacreations.com/tuto/lire/1659-une-grille-responsive-avec-flexbox-et-LESS.html
// Demo : http://codepen.io/raphaelgoetter/pen/ZYjwEB

// Usage in vanilla CSS:
// - <div class="grid-4"> for an equal fourth columns grid container
// - <div class="grid-2-1"> for an uneven columns grid container

// Usage with preprocessors : if you're using Sass, you can config grids variables :
// n = number of columns (default = 4) / g = gutter value (default = 1em)
// example : .grid-perso { @include grid(12, 10px); }
// ... or uneven grids :
// left = left ratio column (default = 2) / right = right ratio column (default = 1)
// example : .grid-perso { @include uneven-grid(2, 1, 10px); }

/* grid container */
[class*="#{$kna-namespace}grid-"] {
  display: flex;
  flex-direction: row;
  flex-wrap: wrap;
  margin-left: -$gutter;
}

/* grid childs */
[class*="#{$kna-namespace}grid-"] > * {
  box-sizing: border-box;
  flex: 0 0 auto;
  width: calc(100% - #{$gutter} - .01px);// @bugfix IE https://github.com/alsacreations/KNACSS/issues/133;
  min-width: 0;
  min-height: 0;
  margin-left: $gutter;
  @include media('>tiny-screen', '<=small-screen') {
    & {
      width: calc(100% * 1 / 2 - #{$gutter} - .01px);
    }
    &.flex-item-double {
      width: calc(100% - #{$gutter} - .01px);
    }
  }
}

// Sass mixins for *equal* columns grid container
// example : .grid-perso { @include grid(12); }
@mixin grid($number:$number,$newgutter:$gutter) {
  @if $newgutter != $gutter {
    margin-left: -$newgutter;
  }
  & > * {
    width: calc(100% * 1 / #{$number} - #{$newgutter} - .01px);
    @if $newgutter != $gutter {
      margin-left: $newgutter;
    }
  }
  & > .#{$kna-namespace}flex-item-double {
    width: calc(100% * 2 / #{$number} - #{$newgutter});
  }
}

// Examples : will be compiled in CSS
@include media('>small-screen') {
  @for $i from 2 through 12 {
    [class*="#{$kna-namespace}grid-#{$i}"] {
        @include grid(#{$i});
    }
  }
}

/* Responsive grid */
// example : .grid-4-small-2 will be 1 column (tiny) then 2 columns (small) then 4 columns
@include media('>tiny-screen', '<=small-screen') {
  [class*="-small-4"] > * {
    width: calc(100% * 1 / 4 - #{$gutter} - .01px);
  }
  [class*="-small-4"] > .flex-item-double {
    width: calc(100% * 1 / 2 - #{$gutter} - .01px);
  }
  [class*="-small-3"] > * {
    width: calc(100% * 1 / 3 - #{$gutter} - .01px);
  }
  [class*="-small-3"] > .flex-item-double {
    width: calc(100% * 2 / 3 - #{$gutter} - .01px);
  }
  [class*="-small-2"] > * {
    width: calc(100% * 1 / 2 - #{$gutter} - .01px);
  }
  [class*="-small-2"] > .flex-item-double {
    width: calc(100% - #{$gutter} - .01px);
  }
  [class*="-small-1"] > * {
    width: calc(100% - #{$gutter} - .01px);
  }
  [class*="-small-1"] > .flex-item-double {
    width: calc(100% - #{$gutter} - .01px);
  }
}


// Sass mixins for *unequal* columns grid container
// example : .grid-perso { @include uneven-grid(2, 1); }
@mixin uneven-grid($left:$left, $right:$right, $newgutter:$gutter) {
  @if $newgutter != $gutter {
    margin-left: -$newgutter;
  }
  > * {
    @if $newgutter != $gutter {
      margin-left: $newgutter;
      width: calc(100% - #{$newgutter});
    }
  }
  @include media('>small-screen') {
    & :nth-child(odd) {
      $size: ($left / ($left + $right)) * 100%;
      width: calc(#{$size} - #{$newgutter});
    }
    & :nth-child(even) {
      $size: ($right / ($left + $right)) * 100%;
      width: calc(#{$size} - #{$newgutter});
    }
  }
}


// Examples : will be compiled in CSS

.#{$kna-namespace}grid-2-1 {
  @include uneven-grid(2,1);
}

.#{$kna-namespace}grid-1-2 {
  @include uneven-grid(1,2);
}

.#{$kna-namespace}grid-3-1 {
  @include uneven-grid(3,1);
}

.#{$kna-namespace}grid-1-3 {
  @include uneven-grid(1,3);
}

.#{$kna-namespace}grid-3-2 {
  @include uneven-grid(3,2);
}

.#{$kna-namespace}grid-2-3 {
  @include uneven-grid(2,3);
}

.#{$kna-namespace}grid-4-1 {
  @include uneven-grid(4,1);
}

.#{$kna-namespace}grid-1-4 {
  @include uneven-grid(1,4);
}

.#{$kna-namespace}pull {
  margin-right: auto;
}
.#{$kna-namespace}push {
  margin-left: auto;
}