Html uld足够了。已使用3n+1更改代码，使其更简单。 <div class='container'> <!-- row 1 --> <div class='item'></div> &l

uld足够了。已使用

3n+1

更改代码，使其更简单。

<div class='container'>
    <!-- row 1 -->
    <div class='item'></div>
    <div class='item'></div>
    <div class='item'></div>
    <!- row 2 -->
    <div class='item'></div>
    <div class='item'></div>
    <div class='item'></div>
    <!-- row 3 -->
    <div class='item'></div>
    <div class='item'></div>
    <div class='item'></div>
    <!-- etc -->
</div>

<div class='container'>
    <!-- row 1 -->
    <div class='item'>{item with red border}</div>
    <div class='item'>{item with purple border}</div>
    <div class='item'>{item with yellow border}</div>
    <!- row 2 -->
    <div class='item'>{item with red border}</div>
    <div class='item'>{item with purple border}</div>
    <div class='item'>{item with yellow border}</div>
    <!-- row 3 -->
    <div class='item'>{item with red border}</div>
    <div class='item'>{item with purple border}</div>
    <div class='item'>{item with yellow border}</div>
    <!-- etc -->
</div>