html – 更少mixin或选择器根据兄弟索引改变位置？

&:nth-of-type(@n) {
    top: @n * 20px;
}

&:nth-of-type(1) {
    .card_offset(1);
}
&:nth-of-type(2) {
    .card_offset(2);
}
&:nth-of-type(3) {
    .card_offset(3);
}
&:nth-of-type(4) {
    .card_offset(4);
}

假设你事先知道元素的数量(或者以某种方式重新计算你的css),那么基本上你有什么工作,如果 put into a loop structure我最初发现 here on stack overflow.

LESS代码

.loop(@indeX) when (@index > 0) {
     //set top amount
    &:nth-of-type(@{index}) { //NOTE: 1.3.3 and under is just @index,not @{index}
        top: @index * 20px;
    }

     // next iteration
     .loop(@index - 1);
}

// end the loop when index is 0
.loop(0) {}

.yourElem {
    @n: 6; //num of elements (could skip this and just put number in)
    .loop(@n);
}

输出

.yourElem:nth-of-type(6) {
  top: 120px;
}
.yourElem:nth-of-type(5) {
  top: 100px;
}
.yourElem:nth-of-type(4) {
  top: 80px;
}
.yourElem:nth-of-type(3) {
  top: 60px;
}
.yourElem:nth-of-type(2) {
  top: 40px;
}
.yourElem:nth-of-type(1) {
  top: 20px;
}