是这样的吗? (不确定为什么要使用混音):

Something like this? (not sure why you're using a mixin):

$orange: #faa21b;
$blue: #005ca8;
$lightBlue: #0079c3;
$teal: #0088a8;
$lightTeal: #009386;
$green: #00a05e;
$lightGreen: #589c45;
$darkOrange: #d4772b;
$orange: #faa21b;
$lightOrange: #f7971f;
$yellow: #f9cc2a;
$lightYellow: #f6ee32;
$i: 1;

@each $color in $orange, $blue, $lightBlue, $teal, $lightTeal, $green, $lightGreen, $darkOrange, $orange, $lightOrange, $yellow, $lightYellow {
    .block-#{$i} {
        span {
            background-color:#{$color};
        }
    }
    $i: $i + 1;
}

输出:

.block-1 span {
  background-color: #faa21b; }

.block-2 span {
  background-color: #005ca8; }

.block-3 span {
  background-color: #0079c3; }

.block-4 span {
  background-color: #0088a8; }

.block-5 span {
  background-color: #009386; }

.block-6 span {
  background-color: #00a05e; }

.block-7 span {
  background-color: #589c45; }

.block-8 span {
  background-color: #d4772b; }

.block-9 span {
  background-color: #faa21b; }

.block-10 span {
  background-color: #f7971f; }

.block-11 span {
  background-color: #f9cc2a; }

.block-12 span {
  background-color: #f6ee32; }