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HTML 

              
                <h1>Float vs Flex vs Grid</h1>
<p>This example shows laying out 6 boxes in all three systems. In each system there is a 6 column layout with one row and a 3 column layout with two rows.</p>

<p>To see the difficulty of workign with both float and flex, as opposed to grid, try adding in 20px gap between columns and rows. Also try changing the number of columns and see how much work each takes. Again grid is MUCH simpler.</p>

<section class="float col-6">
  <header>
    <h2>Float: six column</h2>
   </header>
  
  <div class="box"><p>1</p></div>
  <div class="box"><p>2</p></div>
  <div class="box"><p>3</p></div>
  <div class="box"><p>4</p></div>
  <div class="box"><p>5</p></div>
  <div class="box"><p>6</p></div>
</section>

<section class="float col-3">
  <header>
    <h2>Float: 3 column</h2>
  </header>
  
  <div class="box"><p>1</p></div>
  <div class="box"><p>2</p></div>
  <div class="box"><p>3</p></div>
  <div class="box"><p>4</p></div>
  <div class="box"><p>5</p></div>
  <div class="box"><p>6</p></div>
</section>

<section class="flex col-6">
  <header>
    <h2>Flexbox: six column</h2>
   </header>
  
  <div class="flex-container">
    <div class="box"><p>1</p></div>
    <div class="box"><p>2</p></div>
    <div class="box"><p>3</p></div>
    <div class="box"><p>4</p></div>
    <div class="box"><p>5</p></div>
    <div class="box"><p>6</p></div>
  </div>
</section>

<section class="flex col-3">
  <header>
    <h2>Flexbox: 3 column</h2>
  </header>
  
  <div class="flex-container">
    <div class="box"><p>1</p></div>
    <div class="box"><p>2</p></div>
    <div class="box"><p>3</p></div>
    <div class="box"><p>4</p></div>
    <div class="box"><p>5</p></div>
    <div class="box"><p>6</p></div>
  </div>
</section>

<section class="grid col-6">
  <header>
    <h2>Grid: six column</h2>
   </header>
  
  <div class="grid-container">
    <div class="box"><p>1</p></div>
    <div class="box"><p>2</p></div>
    <div class="box"><p>3</p></div>
    <div class="box"><p>4</p></div>
    <div class="box"><p>5</p></div>
    <div class="box"><p>6</p></div>
  </div>
</section>

<section class="grid col-3">
  <header>
    <h2>Grid: 3 column</h2>
  </header>
  
  <div class="grid-container">
    <div class="box"><p>1</p></div>
    <div class="box"><p>2</p></div>
    <div class="box"><p>3</p></div>
    <div class="box"><p>4</p></div>
    <div class="box"><p>5</p></div>
    <div class="box"><p>6</p></div>
  </div>
</section>
!

CSS 

              
                
/*
====================================
FLOAT
====================================
*/
.float.col-6 .box{
  float: left;
  width: 16.66666%; /* 100/6 = 16.666666 */
}

.float.col-3 .box{
  float: left;
  width: 33.33333%;/* 100/3 = 33.333333 */
}

section.float:after{
/*   Clearfix from: https://css-tricks.com/snippets/css/clear-fix/ */
  content: "";
  display: table;
  clear: both;
}

/*
====================================
FLEXBOX
====================================
*/
.flex-container{
  display: flex;
/*   justify-content: space-between; */
}

/* By default flex items are only as wide as their content so we need to add flex grow to each item so they will fill the space. Note, if tehre were more than 6 items, we would need to specify wrap and each item width to keep 6 columns (see 3 columns below). */
.col-6 .box{
  flex-grow: 1;
}

/* To get 3 columns and force the flex items into two rows we need to tell the flex container that it can wrap items. */
.col-3 .flex-container{
  flex-wrap: wrap;
}

/* Then we need to set a width on the items to get the 3 columns: 100/3 = 33.333333 */
.flex.col-3 .box{
   width:33.333333%; /* 100/3 = 33.333333;*/
}

/*
====================================
GRID
====================================
*/
.grid-container {
  display: grid;
}

.col-6 .grid-container{
  grid-template-columns: repeat(6, 1fr);
}

.col-3 .grid-container{
  grid-template-columns: repeat(3, 1fr);
}


/* ================================================================================================================== */


/*
====================================
GENERAL STYLING
These are just general styling that applies to the whole page. 
====================================
*/
section{
  margin: 3rem 0;
  clear:both;
}
section.col-6{
  margin-top: 6rem;;
}



.box{
  text-align: center;
  outline: 1px solid red;
}

body{
  font-family: sans-serif;
  line-height: 1.4;
}
!

JS
!
999px

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