The Simplest Sass / Flexbox grid ever!

This is a set of simple Sass mixins meant to provide a basic grid for your websites. https://ajy.co/the-simplest-sass-flexbox-grid-ever

See a demo and play with it: http://codepen.io/aaronjamesyoung/pen/yezKpj

Grid mixin usage

This repo provides a mixin called _fg(). You can use this mixin on a grid container. It will distribute the child elements of that container into a grid layout as specified in the mixin.

The mixin accepts three arguments, which I'll explain below:

Number of columns OR layout
Width of gutter between grid columns, in pixels
amount of padding on grid columns, in pixels

Let's break it down, starting with the simplest usage.

Sample HTML

<div clas="grid_container">
  <div class="column_1">Column 1</div>
  <div>Column 2</div>
  <div>Column 3</div>
  <div>Column 4</div>
  <div>Column 5</div>
  <div>Column 6</div>
  <div>Column 7</div>
</div>

Default settings

$_fg_gutter: 24 !default; // gutter between columns. Set as desired.
$_fg_padding: 12 !default; // padding for column boxes. Set as desired, can override for individual columns.

You can override these settings as desired for your project (they can also be custom-set any time you call the _fg() mixin, but we'll get to that in a second).

Specify number of columns

.grid_container { @include _fg(3); }

Here we passed a single number (3) to the grid mixin. This gives us a three-column layout. Each <div> will use 1/3 of the width of the grid container. The rows will wrap - given the above markup, there will be two full rows and Column 7 will be on a third row by itself.

Helper mixin: `_fg_width()`

The above usage is helpful, but we might want to make an exception - perhaps we want a layout with a main content area (2/3 width) and a sidebar (1/3 width). We can override width on a specific column like this:

.column_1 { @include _fg_width(2/3); }

However, we can write a layout more efficiently using the _fg() mixin as below:

Specify per-row layout of columns

Basically, this combines the two above usages.

.grid_container { @include _fg(1 3 2); }

The first argument to the mixin can also be a list - a set of space-separated numbers. This will set up three columns of varying widths. The above mixin is equivalent to calling:

.grid_container { @include _fg(6); } // 1+3+2=6
.grid_container > div:nth-child(3n+2) { @include _fg_width(3/6); } // second column in each row
.grid_container > div:nth-child(3n+3) { @include _fg_width(2/6); } // third column in each row

Thus, each row will have three columns at 1/6 width + 3/6 width + 2/6 width. This should make it easy to set up flexible layouts.

Also note that these two statements are equivalent:

.grid_container { @include _fg(3); }

.grid_container { @include _fg(1 1 1); } // does the same thing!

Set a custom gutter width

.grid_container { @include _fg(3, 45); }

.grid_container { @include _fg(1 3 2, 45); }

Each example above sets a gutter of 45px between each column.

Set custom padding inside columns

.grid_container { @include _fg(2 2 1 1, 45, 30); }

This sets a custom padding of 30px inside each of the columns specified.

A couple more examples all together

@include _fg(2 2 1 1);
  // four columns in each row;
  // 1/3 + 1/3 + 1/6 + 1/6 in each row
  // Uses default settings for grid width and padding inside column elements

@include _fg(5, 20, 10);
  // Five equal columns in each row
  // 20px gutters between each column (overriding the default)
  // each column has 10px padding (overriding the default)

@include _fg(2 1, 60, 0);
  // 2/3 + 1/3 columns in each row
  // 60px gutter between columns
  // columns will have no padding

Breakpoint mixin usage

Breakpoints can be defined as:

$_fg_small: 768; // Unitless, treated as pixels
$_fg_medium: 1024;
$_fg_large: 1280;

@include _fg_breakpoint(small); // or medium or large

This is a pretty standard min-width breakpoint mixin, so you can write your code mobile-first and move up:

body { background: red; @include _fg(1); // on the smallest screens
  @include _fg_breakpoint(small) { @include _fg(2); } // tablet size
  @include _fg_breakpoint(medium) { @include _fg(4); } // desktop size
}

Of course you may set the pixel numbers to whatever you prefer.

You may also pass the breakpoint as an arbitrary width:

@include _fg_breakpoint(600); // evaluates to "@media (min-width: 600)"

Credits

Roland Toth augmented the original mixin to accept a layout; taught me a couple cool SCSS tricks I wasn't aware of
Jayesh Saraf supplied a breakpoint mixin

VilelaBefore/simplest-flexbox-grid