SASS and Compass for Web Designers: The Header

Thanks it works. Just one more thing. How can I transform blankwork or my own grid into flexible grid? Because each time i try to add % after variable, or into some function i get syntax error. I can’t figure out how to make it work.

example:

$columns: 12;
$gutter: 20px;
$column: 60px;
$container: ($columns * $gutter - $gutter) + $columns * $column;
@function column-width($col-value) {
	@return (($col-value * $gutter - $gutter) + $col-value * $column) / $container * 100;
}
.col1 {
	width: column-width(1)%;
}
.col3 {
	width: column-width(3)%;
}
.col4 {
	width: column-width(4)%;
}
.col1, .col2, .col3, .col4 {
	margin-left: $gutter;
	float: left;
	background: $white;
}
.container {
	max-width: $container;
	margin: 0 auto;
}
.wrapper {
	margin-left: -$gutter;
	background: red;
}