当我将鼠标悬停在它们上面时,为什么只有一些CSS网格框在扩展？

Question

我是CSS的网格新手,但我想尝试一下.我有一个3x3盒子的网格.当我将鼠标悬停在一个盒子上时,它应该应该排出整行...但是这不起作用.

当我将鼠标悬停在1屏幕上时,它会完全填满屏幕,当我将鼠标悬停在3屏幕上时,它会开始闪烁并且无法正常工作.

.container {
  display: grid;
  grid-gap: 10px;
  grid-template-columns: repeat(3, minmax(100px, auto));
  grid-template-rows: repeat(3, minmax(100px, auto));
}

[class^="item"] {
  text-align: center;
  box-sizing: border-box;
  padding: 10%;
  font-size: 5em;
  color: #0580d5;
  transition: .2s;
}

[class^="item"]:hover {
  grid-column-start: 1;
  grid-column-end: 4;
}

.item-1 {
  /*grid-area: 1 / 2 / span 2 / span 2;*/
}

.container>div {
  border: 2px solid #0580d5;
  background-color: rgba(40, 180, 240, .3);
  border-radius: 5px;
}

@media only screen and (min-width: 789px) {
  .container {
    grid-template-columns: repeat(3, 1fr);
  }
}

<div class="container">
  <div class="item-1">1</div>
  <div class="item-2">2</div>
  <div class="item-3">3</div>
  <div class="item-4">4</div>
  <div class="item-5">5</div>
  <div class="item-6">6</div>
  <div class="item-7">7</div>
  <div class="item-8">8</div>
  <div class="item-9">9</div>
</div>

Answer 1

这是一个想法，您可以依靠负边距来创建重叠效果，而无需更改结构并使用display:contents

.container {
  display: grid;
  grid-gap: 10px;
  grid-template-columns: repeat(3, minmax(100px, auto));
  grid-template-rows: repeat(3, minmax(100px, auto));
}

[class^="item"] {
  text-align: center;
  box-sizing: border-box;
  padding: 10%;
  font-size: 5em;
  color: #0580d5;
  transition: .2s;
}

[class^="item"]:hover {
  z-index:2; /*we increase the z-index to cover the other*/
  background:
    /*we this to keep the initial background*/
    linear-gradient(rgba(40, 180, 240, .3),rgba(40, 180, 240, .3)),
    #fff;
}

[class^="item"]:nth-child(3n + 1):hover {
  margin-right:calc(-200% - 20px); /* we remove (2 x grid items + 2 x gap) */
}
[class^="item"]:nth-child(3n + 2):hover {
  margin-left:calc(-100% - 10px);
  margin-right:calc(-100% - 10px);
}
[class^="item"]:nth-child(3n + 3):hover {
  margin-left:calc(-200% - 20px);
}

.container>div {
  border: 2px solid #0580d5;
  background-color: rgba(40, 180, 240, .3);
  border-radius: 5px;
}

@media only screen and (min-width: 789px) {
  .container {
    grid-template-columns: repeat(3, 1fr);
  }
}

<div class="container">
  <div class="item-1">1</div>
  <div class="item-2">2</div>
  <div class="item-3">3</div>
  <div class="item-4">4</div>
  <div class="item-5">5</div>
  <div class="item-6">6</div>
  <div class="item-7">7</div>
  <div class="item-8">8</div>
  <div class="item-9">9</div>
</div>