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Layout utilities

Flexbox Layouts

Codebase’s simple flex flexbox layout system enables you to organize wrapped groups of elements in a row (e.g. for a menubar, or a media object) or in a column (e.g. for a card).

Notes on flex

  1. Besides flex (takes effect at all screen widths), there are also responsive prefix flex wrappers: xs:flex, sm:flex, md:flex and lg:flex. The flexbox effect for these responsive wrappers will take effect at extra-small, small, medium or large viewport widths.

    Flex system wrapper Effect
    flex display: flex; for all viewport widths
    xs:flex display: flex; from 568px (default) up
    sm:flex display: flex; from 768px (default) up
    md:flex display: flex; from 1024px (default) up
    lg:flex display: flex; from 1280px (default) up

    Below these breakpoints the child block element layout will be displayed the default way: all stacked in a single column with 100% width.

  2. The flexbox modifier classes documented below (gap-3, flex-wrap, etc.) will all just work as expected with these responsive prefixed flex wrappers – they will only take effect above the specified (lowest) breakpoint.

  3. All flexbox system wrappers affect their immediate child elements (i.e. flex-items).

  4. flex is not used for a pseudo grid system. Instead, Codebase has a real grid that uses CSS Grid Layout.

  5. By default, flex sytems do not wrap their content onto a new row if there is not enough space available. So, if you require wrapping, use flex flex-wrap.

  6. If required in your design, you can override a flexbox at a wider breakpoint the element so that it is back to being a full-width block, using a responsive block utility.

  7. New in v.5.2.9: In addition to the flex setup class, you can also override eah of the flex modifier classes at the xs, sm, md, and lg breakpoint widths — see responsive flex modifier tiers.

Setting up a flex flexbox

All you need is flex:

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<div class="flex">
  <div>One</div>
  <div>Two</div>
  <div>Three</div>
  <div>Four</div>
</div>

The flex wrapper (and its breakpoint width variants; see above), is great for making, e.g. menubars.

Columnar flexbox

You can also turn the flexbox mechanism thorugh 90° using flex flex-column.

Flex columns are great for setting up, e.g. cards.

Stretching flex items

There are two ways that you can expand flex items horizontally to “fill” a row.

Note: it’s also possible to cause individual flex items to grow – see using grow to stretch individual flex items below.

Equal stretching

If you want your flex items to all stretch equally, add flex-grow-equal to the flex wrapper:

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<div class="flex flex-grow-equal">
  <div>One</div>
  <div>Two</div>
  <div>Three</div>
  <div>Four</div>
</div>

flex-grow-equal may be all you need if you require a number of equal width columns (e.g. for a “two up” or “three up”). You can easily use a breakpoint width prefix on the wrapper (e.g. usemd:flex instead of flex), so that your flexbox takes effect only above that viewport width.

Unequal stretching

If you want to make the flex items stretch unequally, according to their content, then add flex-grow-auto to the flex wrapper:

flex flex-grow-auto :

First flex-item
Another flex-item
And a third
Last flex-item in this flexbox set

Flex item wrapping

By default, flex does not cause flex items to wrap if there’s not enough horizontal space for them. If you require wrapping, add flex-wrap to the flexbox wrapper.

To see the effect flex-wrap, make your viewport narrower intil the last item on the example below wraps to a new row. Compage this with the previous example to see the difference.

First flex-item
Another flex-item
And a third
Fourth flex-item in this flexbox set
Here’s another item
We’re not finished yet
There’s more to come
Still not finished
What, you want more?
Really?
Finally, the last flex-item

Using grow to stretch individual flex items

Adding the flexbox grow utility to a flex item will expand it to occupy the available space. grow only take effect inside of a flex wrapper (and only then if above your specified breakpoint width, whether -xs, -sm, -md or -lg).

Examples of grow:

grow
x
x
grow
x
x
<div class="flex">
  <div class="grow">grow</div>
  <div>x</div>
</div>

<div class="flex">
  <div>x</div>
  <div>x</div>
  <div class="grow">grow</div>
  <div>x</div>
  <div>x</div>
  <div>x</div>
</div>

With flex flex-column (and the flex wrapper has style="height: 250px" for this demo):

x
grow
<div class="flex flex-column" style="height: 250px">
  <div>x</div>
  <div class="grow>grow</div>
</div>

Responsive flex modifier tiers

New in Codebase v.5.2.9: In addition to the flex setup class, you can also override eah of the flex modifier classes at the xs, sm, md, and lg breakpoint widths:

  • flex-start / flex-center / flex-end
  • flex-top / flex-middle / flex-bottom
  • flex-column / flex-column-reverse
  • flex-row / flex-row-reverse
  • flex-space-around / flex-space-between / flex-space-evenly
  • flex-grow-auto / flex-grow-equal
  • flex-wrap

So, you can create layout components that use flexbox positioning, orienting, ordering, spacing, growing (stretching), and wrapping differently for different devices.

Example: in this simple menubar, the links are centered for small viewports and right-aligned for medium viewports up:

<nav class="b-thin p-cell flex flex-center md:flex-end gap-2">
  <a href="">About</a>
  <a href="">Blog</a>
  <a href="">Contact</a>
</nav>

Adding gaps

There are two ways to add gaps in flex sets.

Gaps using gap-*

Codebase uses the gap property for flexbox to style flex gaps (i.e. the same gap property as for CSS grid).

Since Codebase v.5.1.0, these have ben set using the same element grid unit spacing variables as are used for the margins and paddings utilities

Element grid measure Utility class suffix
0.5rem -1
1rem -2
1.5rem -3
2rem -4
2.5rem -5
3rem -6

Responsive gap tiers

All of the above gap permutations have 5 responsive tiers: at (all), xs:, sm:, md:, and lg: breakpoints. Like so:

  • Gaps between both rows and columns: gap- / xs:gap- / sm:gap- / md:gap- / lg:gap-
  • Gaps between both columns only: col-gap- / xs:col-gap- / sm:col-gap- / md:col-gap- / lg:col-gap-
  • Gaps between both rows only: row-gap- / xs:row-gap- / sm:row-gap- / md:row-gap- / lg:row-gap-

That makes 90 (flex or grid) gap utilities.

Gap example

flex gap-2 flex-grow-auto flex-wrap

First flex-item
Another flex-item
And a third
Fourth flex-item in this flexbox set
Here’s another item
We’re not finished yet
There’s more to come
Still not finished
What, you want more?
Really?
Finally, the last flex-item

Column Gaps and Row Gaps

flex col-gap-2 flex-grow-auto flex-wrap

First flex-item
Another flex-item
And a third
Fourth flex-item in this flexbox set
Here’s another item
We’re not finished yet
There’s more to come
Still not finished
What, you want more?
Really?
Finally, the last flex-item

flex row-gap-2 flex-grow-auto flex-wrap

First flex-item
Another flex-item
And a third
Fourth flex-item in this flexbox set
Here’s another item
We’re not finished yet
There’s more to come
Still not finished
What, you want more?
Really?
Finally, the last flex-item

Other ways to add white space

flex flex-space-between:

Item
Item
Item
Item
Item

flex flex-space-around:

Item
Item
Item
Item
Item

Alignment of flex items

Horizontal alignment

flex flex-start / flex flex-center / flex flex-end:

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Vertical alignment

flex flex-top / flex flex-middle / flex flex-bottom:

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flex flex-center flex-middle:

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Same as above but with flex-column:

flex flex-column flex-center flex-middle:

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