html - CSS Flexbox(或Grid): 2 columns, 行换行，无增长，内边距

Question

我正在尝试获得像这样的图像(模拟)的结果:

这是我迄今为止尝试过的方法，但显然效果不佳。

.flex-container {
	width: 50%;
	border: 2px dashed blue;
	margin-bottom: 40px;
}
.flex-container > .wrapper {
	display: flex;
	flex-wrap: wrap;
	margin: -5px;
}
.flex-container > .wrapper > input {
	flex-basis: 45%;
	flex-shrink: 1;
	flex-grow: 1;
	margin: 5px;
}

.wrapper.alt1 > input {
	flex-basis: 50%;
	flex-grow: 0;
}

.wrapper.alt2 > input {
	flex-basis: 45%;
	flex-grow: 0;
}

<div class="flex-container">
	<div class="wrapper">
		<input type="button" value="Example">
		<input type="button" value="Example">
		<input type="button" value="Example">
		<input type="button" value="Example">
		<input type="button" value="Example">
	</div>
</div>

<div class="flex-container">
	<div class="wrapper alt1">
		<input type="button" value="Example">
		<input type="button" value="Example">
		<input type="button" value="Example">
		<input type="button" value="Example">
		<input type="button" value="Example">
	</div>
</div>

<div class="flex-container">
	<div class="wrapper alt2">
		<input type="button" value="Example">
		<input type="button" value="Example">
		<input type="button" value="Example">
		<input type="button" value="Example">
		<input type="button" value="Example">
	</div>
</div>

我得到了一个动态的按钮列表，我更愿意将宽度设置为特定的百分比，而不是将其四舍五入到不太具体的值，只是为了让 flex 盒工作。或者，如果有其他方法将列数设置为特定数字，那就没问题了。

编辑:我正在编辑以指定按钮的数量是动态的，因此它可能是奇数或偶数。对于左对齐示例来说这并不重要，但对于居中最终元素示例来说这可能会出现问题。

Answer 1

为此考虑 CSS 网格:

.container {
  width: 50%;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  grid-gap: 5px;
  border: 2px dashed blue;
  margin-bottom: 40px;
}

input {
  grid-column: span 2;
}

.alt :nth-child(odd):last-child {
  grid-column: 2/span 2;
}

<div class="container">
  <input type="button" value="Example">
  <input type="button" value="Example">
  <input type="button" value="Example">
  <input type="button" value="Example">
  <input type="button" value="Example">
</div>


<div class="container alt">
  <input type="button" value="Example">
  <input type="button" value="Example">
  <input type="button" value="Example">
  <input type="button" value="Example">
  <input type="button" value="Example">
</div>

<div class="container alt">
  <input type="button" value="Example">
  <input type="button" value="Example">
  <input type="button" value="Example">
  <input type="button" value="Example">
  <input type="button" value="Example">
  <input type="button" value="Example">
</div>