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HTML 

              
                <main>
		<header>
			<h1>CSS GRIDS <span>x</span> PIET MONDRIAN</h1>
			<p>Reproductions of artwork by Piet Mondrian (1872 - 1944) using CSS Grids</p>
		</header>
		<section class="section--one">
				<div class="painting--one__main">
					<div class="item red"></div>
					<div class="item"></div>
					<div class="item"></div>
					<div class="item inner-grid">
						<div class="inner-item"></div>
						<div class="inner-item"></div>
					</div>
					<div class="item"></div>
					<div class="item"></div>
					<div class="item"></div>
					<div class="item"></div>
					<div class="item"></div>
				</div>
			<p>Composition B (No.II) with Red | 1935</p>
		</section>
		<section class="section--two">
				<div class="painting--two__main">
					<div class="item"></div>
					<div class="item"></div>
					<div class="item inner-grid-2">
						<div class="inner-item blue"></div>
						<div class="inner-item"></div>
						<div class="inner-item"></div>
					</div>
				</div>
			<p>Vertical Composition with Blue and White | 1936</p>
		</section>
		<section class="section--three">
				<div class="painting--three__main">
					<div class="item red"></div>
					<div class="item"></div>
					<div class="item"></div>
					<div class="item inner-grid-1">
						<div class="inner-grid-2">
							<div class="inner-item"></div>
							<div class="inner-grid-3">
								<div class="inner-item yellow"></div>
								<div class="inner-item black"></div>
							</div>
						</div>
						<div class="inner-grid-4">
							<div class="inner-item blue"></div>
							<div class="inner-item"></div>
						</div>
					</div>
				</div>
			<p>Composition | 1929</p>
		</section>
	</main>
!

CSS 

              
                article,aside,details,figcaption,figure,footer,header,hgroup,nav,section,summary{display:block;}audio,canvas,video{display:inline-block;}audio:not([controls]){display:none;height:0;}[hidden]{display:none;}html{font-family:sans-serif;-webkit-text-size-adjust:100%;-ms-text-size-adjust:100%;}a:focus{outline:thin dotted;}a:active,a:hover{outline:0;}h1{font-size:2em;}abbr[title]{border-bottom:1px dotted;}b,strong{font-weight:700;}dfn{font-style:italic;}mark{background:#ff0;color:#000;}code,kbd,pre,samp{font-family:monospace, serif;font-size:1em;}pre{white-space:pre-wrap;word-wrap:break-word;}q{quotes:\201C \201D \2018 \2019;}small{font-size:80%;}sub,sup{font-size:75%;line-height:0;position:relative;vertical-align:baseline;}sup{top:-.5em;}sub{bottom:-.25em;}img{border:0;}svg:not(:root){overflow:hidden;}fieldset{border:1px solid silver;margin:0 2px;padding:.35em .625em .75em;}button,input,select,textarea{font-family:inherit;font-size:100%;margin:0;}button,input{line-height:normal;}button,html input[type=button],/* 1 */
input[type=reset],input[type=submit]{-webkit-appearance:button;cursor:pointer;}button[disabled],input[disabled]{cursor:default;}input[type=checkbox],input[type=radio]{box-sizing:border-box;padding:0;}input[type=search]{-webkit-appearance:textfield;-moz-box-sizing:content-box;-webkit-box-sizing:content-box;box-sizing:content-box;}input[type=search]::-webkit-search-cancel-button,input[type=search]::-webkit-search-decoration{-webkit-appearance:none;}textarea{overflow:auto;vertical-align:top;}table{border-collapse:collapse;border-spacing:0;}body,figure{margin:0;}legend,button::-moz-focus-inner,input::-moz-focus-inner{border:0;padding:0;}

.clearfix:after {visibility: hidden; display: block; font-size: 0; content: " "; clear: both; height: 0; }

* { -moz-box-sizing: border-box; -webkit-box-sizing: border-box; box-sizing: border-box; }

$black : #333;
$blackOil : #181A19;
$white : #FFF;
$redOil : #A11E02;
$yellowOil: #D1BE37;
$grey : #DEDEDE;
$blueOil : #2E398B;
$canvas : #EEE;

$font-family : "Roboto Mono", monospace;

body {
	font-family:$font-family;
	font-size:14px;
	background: $grey;
}

main {
	max-width:900px;
	margin:0 auto;
	background:$white;
	box-shadow:0 0 2px $canvas;
}

header {
	text-align:center;
	padding:40px 40px 0 40px;

	h1 {
		margin-top: 0;

		span {
			position: relative;
			top:-2px;

		}
	}
}

section {
	padding:40px;
	text-align:center;
}

//painting 1

.painting--one__main {
	width:300px;
	height:380px;
	position:relative;
	margin:0 auto 40px auto;
	background:$blackOil;
	display:grid;
	grid-template-columns: 130px 62px 92px;
  grid-template-rows: 115px 124px 121px;
  grid-column-gap: 8px;
  grid-row-gap: 10px;
  box-shadow:0px 4px 6px $grey;
  overflow:hidden;

  .item {
  	background:$canvas;
  }

  .red {
  	background:$redOil;
  }

  .inner-grid {
  	display:grid;
  	grid-template-columns: 8px 117px;
  	grid-column-gap: 5px;
  	background: $blackOil;
  }

  .inner-item {
  	background:$canvas;
  }
}

//painting 2

.painting--two__main {
	width:245px;
	height:500px;
	position:relative;
	margin:0 auto 40px auto;
	background:$blackOil;
	display:grid;
	grid-template-columns: 30px 109px 95px;
  grid-column-gap: 8px;
  box-shadow:0px 4px 6px $grey;
  overflow:hidden;

  .item {
  	background:$canvas;
  }

  .inner-grid-2 {
  	display:grid;
  	grid-template-rows: 42px 338px 104px;
  	grid-row-gap: 8px;
  	background: $blackOil;
  }

  .inner-item {
  	background:$canvas;
  }

  .blue {
  	background:$blueOil;
  }
}

//painting 3

.painting--three__main {
	width:300px;
	height:300px;
	position:relative;
	margin:0 auto 40px auto;
	background:$blackOil;
	display:grid;
	grid-template-columns: 84px 208px;
  grid-column-gap: 8px;
  grid-template-rows: 90px 202px;
  grid-row-gap: 8px;
  box-shadow:0px 4px 6px $grey;
  overflow:hidden;

  .item {
  	background:$canvas;
  }

  .inner-grid-1 {
  	display:grid;
  	grid-template-columns: 185px 15px;
  	grid-column-gap: 8px;
  	background: $blackOil;
  }

  .inner-grid-2 {
  	display:grid;
  	grid-template-rows: 184px 10px;
  	grid-row-gap: 8px;
  	background: $blackOil;
  }

  .inner-grid-3 {
  	display:grid;
  	grid-template-columns: 118px 58px;
  	grid-column-gap: 8px;
  	background: $blackOil;
  }

  .inner-grid-4 {
  	display:grid;
  	grid-template-rows: 74px 120px;
  	grid-row-gap: 8px;
  	background: $blackOil;
  }

 	.inner-item {
 		background: $canvas;
 	}

 	.red {
 		background:$redOil;
 	}

 	.blue {
 		background: $blueOil;
 	}

 	.yellow {
 		background: $yellowOil;
 	}
 	.black {
 		background: $blackOil;
 	}
}
!

JS 

              
                //Just for fun...starting to learn CSS by recreating the work of Piet Mondrian
!
999px

Console