html - 使用固定宽度的列在 CSS 网格中居中

Question

我正在尝试制作一个简单的以 CSS 为中心的网格布局。
我知道当我使用 justify-items: center ，网格容器内的元素应该水平对齐，但是当我像这样以像素为单位指定列宽时 grid-template-columns: repeat(3, 100px)整个电网恢复正常。那么有什么方法可以使网格项居中但同时以像素为单位指定列宽？
这是我的例子:

    <div class="container">
        <div class="item"></div>
        <div class="item"></div>
        <div class="item"></div>
        <div class="item"></div>
        <div class="item"></div>
        <div class="item"></div>
        <div class="item"></div>
        <div class="item"></div>
        <div class="item"></div>
    </div>

.container {
    background-color: #aa96da;
    display: grid;
    justify-items: center;
    grid-gap: 20px;
    grid-template-rows: repeat(3, 1fr);

    /*Only if I change this 100px to '1fr' the justify-items will work */
    grid-template-columns: repeat(3, 100px);
}

.item {
    width: 100px;
    height: 100px;
    background-color: green;
}

Answer 1

更改 justify-items至 justify-content它应该工作。

.container {
    background-color: #aa96da;
    display: grid;
    /* justify-items: center; */
    justify-content: center;
    grid-gap: 20px;
    grid-template-rows: repeat(3, 1fr);

    /*Only if I change this 100px to '1fr' the justify-items will work */
    grid-template-columns: repeat(3,  100px);
}

.item {
    width: 100px;
    height: 100px;
    background-color: green;
}

 <div class="container">
    <div class="item"></div>
    <div class="item"></div>
    <div class="item"></div>
    <div class="item"></div>
    <div class="item"></div>
    <div class="item"></div>
    <div class="item"></div>
    <div class="item"></div>
    <div class="item"></div>
</div>