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HTML 

              
                <h1>Flexbox layout patterns.</h1>
<p>Keep a simple dom structure. No wrapper for Flexbox.</p>
<section class="HolyGrail">
 <header><h2>Holy Grail</h2>header</header>
 <main>main</main>
 <nav>nav</nav>
 <aside>aside</aside>
 <footer>footer</footer>
</section>
<section class="sideways">
 <header><h2>Lay "Holy Grail" down on side.</h2>header</header>
 <main>main</main>
 <nav>nav</nav>
 <aside>aside</aside>
 <footer>footer</footer>
</section>
<section class="oneColumn">
 <header><h2>One Column.</h2>header</header>
 <main>main</main>
 <nav>nav</nav>
 <aside>aside</aside>
 <footer>footer</footer>
</section>
<section class="horizontalNav">
 <nav>
  <h2>Horizontal nav.</h2>
  <ul>
   <li><a href="#">link</a></li>
   <li><a href="#">link</a></li>
   <li><a href="#">link</a></li>
   <li><a href="#">link</a></li>
   <li><a href="#">link</a></li>
   <li><a href="#">link</a></li>
   <li><a href="#">link</a></li>
  </ul>
 </nav>
</section>
<section class="grid">
 <h2>Grid <small>space-between and psuedo trick makes nicely last row.</small></h2>
 <ul>
  <li>1</li>
  <li>2</li>
  <li>3</li>
 </ul>
 <ul>
  <li>1</li>
  <li>2</li>
  <li>3</li>
  <li>4</li>
 </ul>
 <ul>
  <li>1</li>
  <li>2</li>
  <li>3</li>
  <li>4</li>
  <li>5</li>
 </ul>
</section>
<section class="masonry">
 <h2>Masonry</h2>
 <ul>
  <li>1</li>
  <li>2</li>
  <li>3</li>
  <li>4</li>
  <li>5</li>
  <li>6</li>
  <li>7</li>
  <li>8</li>
  <li>9</li>
  <li>10</li>
  <li>11</li>
  <li>12</li>
 </ul>
</section>
<section class="masonry-v">
 <h2>Masonry (virtical)</h2>
 <ul>
  <li>1</li>
  <li>2</li>
  <li>3</li>
  <li>4</li>
  <li>5</li>
  <li>6</li>
  <li>7</li>
  <li>8</li>
  <li>9</li>
  <li>10</li>
  <li>11</li>
  <li>12</li>
 </ul>
</section>
!

CSS 

              
                body > * {
 width: 30rem;
 margin: 2rem auto;
}
section {
 display: flex;
}
section > * {
 padding:1em;
 box-sizing: border-box;
}
header {
 background-color: hsl(0,100%,80%);
 order: 1;
}
footer {
 background-color: hsl(72,70%,80%);
 order: 5;
}
main   {
 background-color: hsl(144,70%,80%);
 order: 3;
}
nav    {
 background-color: hsl(216,70%,80%);
 order: 2;
}
aside  {
 background-color: hsl(288,70%,80%);
 order: 4;
}

.HolyGrail {
 flex-direction: row;
 flex-wrap: wrap;
}
.HolyGrail header,
.HolyGrail footer {
 flex-basis: 100%;
}
.HolyGrail main {
 flex-grow: 1;
}
.HolyGrail nav {
 flex-basis: 25%;
}
.HolyGrail aside {
 flex-basis: 25%;
}

.sideways {
 flex-direction: column;
 flex-wrap: wrap;
 height: 16em;
}
.sideways main,
.sideways nav,
.sideways aside {
 flex-basis: 20%;
 width: 40%;
}
.sideways main {
 flex-grow: 1;
}
.sideways footer {
 flex-basis: 100%;
 width: 20%;
}
.sideways header {
 width: 40%;
 flex-basis: 100%;
}
.oneColumn {
 flex-direction: column;
 flex-wrap: nowwrap;
}

.horizontalNav {
 display: block;
}
.horizontalNav nav {
 display: block;
}
.horizontalNav ul {
 display: flex;
 justify-content: space-between;
 list-style: none;
 padding-left: 0;
 background-color: rgba(0,0,0,0.1);
}
.horizontalNav li {
 flex-basis: auto;
}
.horizontalNav a {
 text-decoration: none;
 padding: 0.5em 1em;
 background-color: rgba(0,0,0,0.3);
 color: #fff;
 display: block;
}
.grid {
 display: block;
 background-color: #ccc;
 padding-bottom: 0.1em;
}
.grid > h2 {
 padding: 2rem 1rem 1rem;
 margin-bottom: 0;
}
.grid ul {
 display: flex;
 list-style: none;
 flex-flow: row wrap;
 justify-content: space-between;
 background-color: rgba(0,100,0,0.2);
 margin: 0 1em 2em;
 align-content: space-between;
 padding-bottom: 0;
}
.grid ul > * {
 flex-basis: 32%;
 max-width: 32%; /* IE11 bugfix */
 background-image: linear-gradient(45deg,#888,#333);
 height: 4em;
 margin-bottom: 1em;
 background-position: 0 0;
 box-sizing: border-box;
 padding: 0.5em;
 color: #fff;
}
/* psuedo trick. */
.grid ul::after {
 content: "";
 flex-basis: 32%;
 background-color: rgba(200,0,0,0.3);
 display: block;
 height: 0;
}
.grid ul li:last-of-type:nth-of-type(3n) {
 margin-right: -34%;
}
.masonry {
 display: block;
 background-color: #ecc;
 padding-bottom: 0.1em;
}
.masonry > h2 {
 padding: 2rem 1rem 1rem;
 margin-bottom: 0;
}
.masonry ul {
 display: flex;
 flex-flow: row wrap;
 list-style: none;
 justify-content: space-between;
 background-color: rgba(50,100,0,0.2);
 margin: 0 1em 2em;
}
.masonry ul > * {
 flex-basis: 20%;
 background-image: linear-gradient(45deg,#a88,#633);
 height: 4em;
 flex-grow: 1;
 margin: 1px;
 box-sizing: border-box;
 padding: 0.5em;
 color: #fff;
}
.masonry ul > :nth-of-type(2n+1) {
 flex-basis: 30%;
}
.masonry-v {
 display: block;
 background-color: #ecc;
 padding-bottom: 0.1em;
}
.masonry-v > h2 {
 padding: 2rem 1rem 1rem;
 margin-bottom: 0;
}
.masonry-v ul {
 display: flex;
 flex-flow: row wrap;
 list-style: none;
 justify-content: space-between;
 background-color: rgba(50,100,0,0.2);
 margin: 0 1em 2em;
 padding-bottom: 3em;
}
.masonry-v ul > * {
 flex-basis: calc(50% - 2px);
 max-width: calc(50% - 2px); /* IE11 bugfix */
 background-image: linear-gradient(45deg,#a88,#633);
 height: 4em;
 margin: 1px;
 box-sizing: border-box;
 padding: 0.5em;
 color: #fff;
}
.masonry-v ul > :nth-of-type(2n) {
 transform: translateY(50%);
}
!

JS
!
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