_responsive.scss

@import "compass/css3";

@mixin column($colstart,$colend,$margin:margin,$fixed:fluid, $in-column:in-1-12, $colmargin:no-margin) {
	width: get-width($colstart,$colend,$margin, $fixed, $in-column, $colmargin);
	@if ($colend - $colstart +1) != 12 {
		float:left;
	}
	@if $margin == 'no-margin' {
		margin-left:0;
		margin-right:0;
	} @else if $margin == 'no-margin-left' {
		@if ($colend == 12) {
			margin-right:1.639344262295%;
		} @else {
			margin-right:0.819672131148%;
		}
		margin-left:0;
	} @else if $margin == 'no-margin-right' {
		@if ($colstart == 1) {
			margin-left: 1.639344262295%;
		} @else {
			margin-left:0.819672131148%;
		}
		margin-right:0;
	} @else {
		@if ($colstart == 1) {
			margin-left:1.639344262295%;
		} @else {
			margin-left:0.819672131148%;
		}

		@if ($colend == 12) {
			margin-right:1.639344262295%;
		} @else {
			margin-right:0.819672131148%;
		}
		
	}
	box-sizing: border-box;
	
}
@function get-width($colstart,$colend,$margin, $fixed:fluid,  $in-column:in-1-12, $colmargin:no-margin){
	$incol-range: str_slice($in-column,4);
	$hyphen-index: str_index($incol-range, "-");
	$incol-start: number(str_slice($incol-range, 0, ($hyphen-index - 1)));
	$incol-end: number(str_slice($incol-range, ($hyphen-index + 1)));
	$basewidth: 0;
	$in-width: 0;

	$colnum: ($colend - $colstart +1);
	//fixed grid
	@if ($fixed == 'fixed') {

		//basewidth is the width with margins but no outer margins. Allow for pixel width value for $in-column like "in-918"
		@if($hyphen-index == 0) {
			$in-width: number($incol-range);
		} @else {
			$in-width: get-width($incol-start, $incol-end, $colmargin);
			$in-width: ($in-width / ($in-width * 0 + 1)) * 9.76;
		}
		$basewidth: (round(($colnum * .08333333) * $in-width )) * 1px;
		$basemargin: ((8/960) * ($in-width));
		//remove margins from width if the element has margins
		@if($margin == 'no-margin-left' or $margin == 'no-margin-right') {
			$basewidth: $basewidth - $basemargin;
		} @else if ($margin == 'margin') {
			$basewidth: $basewidth - (2 * $basemargin);
		}
		//remove double margins if it has outer gutters
		@if ($colstart == 1 and ( $margin == 'no-margin-right' or $margin == 'margin')) {
			$basewidth: $basewidth - $basemargin;
		}
		@if ($colend == 12 and ( $margin == 'no-margin-left' or $margin == 'margin')) {
			$basewidth: $basewidth - $basemargin;
		}
			
	}
	//fluid grid
	@else {
		@if ($margin == 'no-margin') {
			@if ($colnum == 12) {
				$basewidth: 100%;
			} 
			@else {
				$basewidth: (($colnum/12) * (960/976)) * 100%;
			}

			@if ($colnum < 12 and ($colstart == 1 or $colend == 12)) {
				$basewidth: $basewidth + (($colnum/12) * 8);
			}
		}
		@else if ($margin == 'no-margin-left') {
			@if ($colstart == '1') {
                $basewidth: (($colnum * 80) / 976) * 100%;
            }
            @else {
                $basewidth: ((($colnum * 80) - 8) / 976) * 100%;
            }
		}
        @else if ($margin == 'no-margin-right') {
			@if ($colend == '12') {
                $basewidth: (($colnum * 80) / 976) * 100%;
            }
            @else {
                $basewidth: ((($colnum * 80) - 8) / 976) * 100%;
            }
		}
		@else {
			$basewidth: ((($colnum * 80) - 16) / 976) * 100%;
		}
	}
	@return $basewidth;
}
@function max($pixels) {
  @return 'max-width:'#{$pixels/16.0}'em'
}
@function min($pixels) {
  @return 'min-width:'#{$pixels/16.0}'em'
}

@function set-margin($colnum,$margin){
	@if $margin == 'margin' {
		@return ((($colnum * 80) + 16) / 960) * 100%;
	}
	@else {
		@return ((($colnum * 80) + 8) / 960) * 100%;
	}
}

@mixin startat($begin, $margin:margin) {
	$newmargin: $begin - 1;
	margin-left: set-margin($newmargin, $margin);
}

//convert a string to a number
@function number($string) {
	// Matrices
	$strings: '0' '1' '2' '3' '4' '5' '6' '7' '8' '9';
	$numbers:  0   1   2   3   4   5   6   7   8   9;
  
	// Result
	$result: 0;

	// Looping through all characters
	@for $i from 1 through str-length($string) {
		$character: str-slice($string, $i, $i);
		$index: index($strings, $character);
    
		@if not $index {
			@warn "Unknown character `#{$character}`.";
			@return false;
		}
      
		$number: nth($numbers, $index);
		$result: $result * 10 + $number;
	}
  
  @return $result;
}