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HTML 

              
                <div id="seasons">
	<div id="winterintospring">
		<div class="">Winter into Spring&nbsp;1</div>
		<div>Winter into Spring&nbsp;2</div>
		<div>Winter into Spring&nbsp;3</div>
		<div>Winter into Spring&nbsp;4</div>
		<div>Winter into Spring&nbsp;5</div>
		<div>Winter into Spring&nbsp;6</div>
		<div>Winter into Spring&nbsp;7</div>
		<div>Winter into Spring&nbsp;8</div>
	</div>
	<div id="summer">
		<div>Summer&nbsp;1</div>
		<div>Summer&nbsp;2</div>
		<div>Summer&nbsp;3</div>
		<div>Summer&nbsp;4</div>
	</div>
	<div id="autumn">Autumn</div>
</div>
!

CSS 

              
                /* outer -ms-grid */

#seasons,
#winterintospring,
#summer
{
	display: -ms-grid;
}

#seasons
{
	-ms-grid-rows: (1fr 0.25rem)[3] auto;
	-ms-grid-columns: 1fr;
}

#winterintospring
{
	-ms-grid-row-span: 3;
	
	-ms-grid-rows: (1fr 0.25rem)[3] 1fr;
	-ms-grid-columns: 1fr 0.25rem 1fr;
}

#summer
{
	-ms-grid-row: 5;
	
	-ms-grid-rows: 1fr 0.25rem 1fr;
	-ms-grid-columns: 1fr 0.25rem 1fr;
}

#autumn
{
	-ms-grid-row: 7;
}

@media (min-width: 36em)
{
	#seasons
	{
		-ms-grid-rows: 1fr 0.25rem 1fr;
		-ms-grid-columns: 1fr 0.25rem 1fr;
	}
	
	#winterintospring
	{
		-ms-grid-row-span: 1;
		-ms-grid-column-span: 3;
	
		-ms-grid-rows: 1fr 0.25rem 1fr;
		-ms-grid-columns: (1fr 0.25rem)[3] 1fr;
	}

	#summer
	{
		-ms-grid-row: 3;
	}

	#autumn
	{
		-ms-grid-row: 3;
		-ms-grid-column: 3;
	}
}

@media (min-width: 48em)
{
	#seasons
	{
		-ms-grid-rows: 1fr 0.25rem auto;
		-ms-grid-columns: 2fr 0.25rem 1fr;
	}
	
	#winterintospring
	{
		-ms-grid-column-span: 1;
	}

	#summer
	{
		-ms-grid-row: 1;
		-ms-grid-column: 3;
	}

	#autumn
	{
		-ms-grid-row: 3;
		-ms-grid-column: 1;
		-ms-grid-column-span: 7;
	}
}

/* inner -ms-grid */

.double:first-child,
#summer .double:nth-child(3)
{
	-ms-grid-column-span: 3;
}

.large:first-child
{
	-ms-grid-row-span: 3;
	-ms-grid-column-span: 3;
}

#winterintospring > :nth-child(2),
#summer > :nth-child(2)
{
	-ms-grid-row: 1;
	-ms-grid-column: 3;	
}

#winterintospring > :nth-child(3),
#winterintospring > .double:first-child ~ :nth-child(2),
#summer > :nth-child(3)
{
	-ms-grid-row: 3;
	-ms-grid-column: 1;	
}

#winterintospring > :nth-child(4),
#winterintospring > .double:first-child ~ :nth-child(3),
#summer > :nth-child(4)
{
	-ms-grid-row: 3;
	-ms-grid-column: 3;	
}

#winterintospring > :nth-child(5),
#winterintospring > .double:first-child ~ :nth-child(4),
#winterintospring > .large:first-child ~ :nth-child(2)
{
	-ms-grid-row: 5;
	-ms-grid-column: 1;	
}

#winterintospring > :nth-child(6),
#winterintospring > .double:first-child ~ :nth-child(5),
#winterintospring > .large:first-child ~ :nth-child(3)
{
	-ms-grid-row: 5;
	-ms-grid-column: 3;	
}

#winterintospring > :nth-child(7),
#winterintospring > .double:first-child ~ :nth-child(6),
#winterintospring > .large:first-child ~ :nth-child(4)
{
	-ms-grid-row: 7;
	-ms-grid-column: 1;	
}

#winterintospring > :nth-child(8),
#winterintospring > .double:first-child ~ :nth-child(7),
#winterintospring > .large:first-child ~ :nth-child(5)
{
	-ms-grid-row: 7;
	-ms-grid-column: 3;	
}

@media (min-width: 36em)
{
	#winterintospring > :nth-child(3),
	#winterintospring > .double:first-child ~ :nth-child(2),
	#winterintospring > .large:first-child ~ :nth-child(2)
	{
		-ms-grid-row: 1;
		-ms-grid-column: 5;	
	}

	#winterintospring > :nth-child(4),
	#winterintospring > .double:first-child ~ :nth-child(3),
	#winterintospring > .large:first-child ~ :nth-child(3)
	{
		-ms-grid-row: 1;
		-ms-grid-column: 7;	
	}
	
	#winterintospring > :nth-child(5),
	#winterintospring > .double:first-child ~ :nth-child(4)
	{
		-ms-grid-row: 3;
		-ms-grid-column: 1;	
	}

	#winterintospring > :nth-child(6),
	#winterintospring > .double:first-child ~ :nth-child(5)
	{
		-ms-grid-row: 3;
		-ms-grid-column: 3;	
	}

	#winterintospring > :nth-child(7),
	#winterintospring > .double:first-child ~ :nth-child(6),
	#winterintospring > .large:first-child ~ :nth-child(4)
	{
		-ms-grid-row: 3;
		-ms-grid-column: 5;	
	}

	#winterintospring > :nth-child(8),
	#winterintospring > .double:first-child ~ :nth-child(7),
	#winterintospring > .large:first-child ~ :nth-child(5)
	{
		-ms-grid-row: 3;
		-ms-grid-column: 7;	
	}
}

/* outer & inner grids */

#seasons,
#winterintospring,
#summer
{
	display: grid;	
	grid-gap: 0.25rem;
}

#seasons
{
	grid-template: repeat(3, 1fr) auto / 1fr;
	grid-template-areas:
		"winterintospring"
		"winterintospring"
		"summer"
		"autumn";
}

#winterintospring
{
	grid-area: winterintospring;
	grid-template: repeat(4, 1fr) / repeat(2, 1fr);
}

#summer
{
	grid-area: summer;
	grid-template: repeat(2, 1fr) / repeat(2, 1fr);
}

#autumn
{
	grid-area: autumn;
}

@media (min-width: 36em)
{
	#seasons
	{
		grid-template: repeat(2, 1fr) / repeat(2, 1fr);
		grid-template-areas:
			"winterintospring winterintospring"
			"summer           autumn";
	}
	
	#winterintospring
	{
		grid-template: repeat(2, 1fr) / repeat(4, 1fr);
	}
}

@media (min-width: 48em)
{
	#seasons
	{
		grid-template: 1fr auto / 2fr 1fr;
		grid-template-areas:
			"winterintospring summer"
			"autumn           autumn";
	}
}

.double:first-child,
#summer .double:nth-child(3)
{
	grid-column-end: span 2;
}

.large:first-child
{
	grid-column-end: span 2;
	grid-row-end: span 2;
}

.double:first-child ~ :last-child,
#summer .double:nth-child(3) ~ :last-child,
.large:first-child ~ :nth-last-child(3),
.large:first-child ~ :nth-last-child(3) ~ *
{
	display: none !important;
}

/* other stuff */

#seasons > * > *,
#autumn
{
	padding: 0.5rem;
	overflow: hidden;
	font: 2em/1 LiebeDoris, Calibri;	
}

#seasons > * > *
{
	display: flex;
	align-items: flex-end;
}

#winterintospring > *
{
	background: hsl(100, 50%, 50%);
	background: hsl(100deg 50% 50%);
}

#summer > *
{
	background: hsl(50, 80%, 60%);
	background: hsl(50deg 80% 60%);
}

#autumn
{
	background: hsl(20, 70%, 50%);
	background: hsl(20deg 70% 50%);
}
!

JS 

              
                (function ()
{
	function adjustHeight()
	{
		const summerElement = document.querySelector('#summer');
		summerElement.style.height = summerElement.offsetWidth + 'px';
	}

	document.addEventListener('DOMContentLoaded', adjustHeight);
	window.addEventListener('resize', adjustHeight);
})();
!
999px

Console