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                <h1>Responsive margins with minimum and maximum values</h1>
<p>This is adding a margin top which has a min value and max value. It will porportionally change between two predefined breakpoints.</p>
<p>This is helpful because purely using VW or VH often ends up with small screens having nearly no margin and large ones having excessive margins.</p>
<p>Based on <a href="">Turely Fluid Typography With vh and vw Units</a> by <a href="">Michael Riethmuller</a>.</p>
<p>The article mentions poor support below IE11 and Safari 8 but I've tested in IE9 and Safari 6.2 and works fine.</p>


                $min-section: 5em;
$max-section: 15em;
$min-mq: 40em;
$max-mq: 60em;

@function strip-unit($number) {
  @if type-of($number) == 'number' and not unitless($number) {
    @return $number / ($number * 0 + 1);

  @return $number;

@function responsive-size($min-size, $max-size, $min-media, $max-media) {
	@return calc( #{$min-size} + #{(strip-unit($max-size) - strip-unit($min-size))} * ( 100vw - #{$min-media} ) / (#{strip-unit($max-media)} - #{strip-unit($min-media)}) )

body {
	margin-top: $min-section;

@media(min-width: $min-mq) {
	body {
		margin-top: responsive-size($min-section, $max-section, $min-mq, $max-mq);

@media(min-width: $max-mq) {
	body {
		margin-top: $max-section;

/* styling purposes */
html {
	background: #e4e4e4;

body {
	background-color: white;
	padding: 3em;
	max-width: 35em;
	margin-left: auto;
	margin-right: auto;
	line-height: 1.6;
h1 {
	line-height: 1.2;