金魚都能懂的網頁切版：20

旋轉拼接方塊

https://codepen.io/mikeyam/pen/jOrOMEr?editors=1100

HTML部分使用ul和li做結構

    <ul>
        <li class="box1">text1</li>
        <li class="box2">text2</li>
        <li class="box3">text3</li>
        <li class="box4">text4</li>
        <li class="box5">text5</li>
        <li class="box6">text6</li>
        <li class="box7">text7</li>
        <li class="box8">text8</li>
        <li class="box9">text9</li>
    </ul>

外層用flex排版，li排列出正方形，並用outline做提醒

ul{
    width: 1200px;
    margin: auto;
    padding: 100px 0;
    display: flex;
    flex-wrap: wrap;
}
li{
    width: 200px;
    height: 200px;
    text-align: center;
    line-height: 200px;
    /* outline: 1px solid brown; */
    margin: 0 60px -40px;
    position: relative;
    font-size: 30px;
}

用偽元素並用transform旋轉45度

li::before{
    content: '';
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    z-index: -1;
    /* outline: 1px solid #00f; */
    transform: rotate(45deg);
}

四跟七做位移並搭配chrome瀏覽器檢查，來調整最適當距離

li:nth-child(n+4){
    left: 160px;
}
li:nth-child(n+7){
    left: 0;
}
li:hover{
    color: #fff;
}
li:hover::before{
    background-color: #000;
}
.box1::before{background-color: #3ed0cd;}
.box2::before{background-color: #b2e086;}
.box3::before{background-color: #ef8899;}
.box4::before{background-color: #fc7b51;}
.box5::before{background-color: #2fccf9;}
.box6::before{background-color: #5f539b;}
.box7::before{background-color: #ffa55e;}
.box8::before{background-color: #fce920;}
.box9::before{background-color: #7cc85c;}