Grid、Flex常用布局的异同

全局class说明

.grid {
	display: grid;
}
.flex {
	display: flex;
}
.item {
	height: 100px;
}

水平垂直居中

Grid实现

<section class="center container grid">Grid 水平垂直居中</section>

justify-content: center; // 或justify-items: center;
align-items: center;

Flex实现

<section class="center container flex">Flex 水平垂直居中</section>

.flex.center {
	justify-content: center;
	align-items: center;
}

两栏（左侧固定宽度，右侧自适应）

Grid实现

<section class="items container grid">
	<div class="item">左栏</div>
	<div class="item">右栏</div>
</section>

.grid.items {
	grid-template: 1fr / 100px 1fr;
	height: 100px;
	.item {
		&:nth-of-type(1) {
			background: olive;
		}
		&:nth-of-type(2) {
			background: aquamarine;
		}
	}
}

Flex实现

<section class="items container flex">
	<div class="item">左栏</div>
	<div class="item">右栏</div>
</section>

.flex.items {
	.item {
		&:nth-of-type(1) {
			flex: 0 0 100px;
			background: olive;
		}
		&:nth-of-type(2) {
			flex: 1 1 auto;
			background: aquamarine;
		}
	}
}

双飞翼

Grid实现

<section class="three-columns container grid">
	<div class="item center">center</div>
	<div class="item left">left</div>
	<div class="item right">right</div>
</section>

.grid.three-columns {
	grid-template-columns: 100px 1fr 100px;
	grid-template-areas: "left center right";
	.item {
		height: 100px;
		&.center {
			grid-area: center;
			background: olive;
		}
		&.left {
			// order: -1; // 也支持order，则不用再使用grid-template-areas
			background: aquamarine;
		}
		&.right {
			background: darkcyan;
		}
	}
}

Flex实现

<section class="three-columns container flex">
	<div class="item center">center</div>
	<div class="item left">left</div>
	<div class="item right">right</div>
</section>

.flex.three-columns {
	.item {
		height: 100px;
		&.center {
			flex: 1 1 auto;
			order: 1;
			background: olive;
		}
		&.left {
			flex: 0 0 100px;
			background: aquamarine;
		}
		&.right {
			flex: 0 0 100px;
			order: 2;
			background: darkcyan;
		}
	}
}

stick-footer

css3之前的stick footer布局的写法十分晦涩难懂，现在使用Grid、Flex就十分简单啦

Grid实现

<section class="stick-footer container grid">
	<h2>sticker</h2>
	<main>
		<li>content</li>
	</main>
	<button>footer</button>
</section>

.grid.stick-footer {
	grid-template-rows: auto 1fr auto;
	min-height: 200px;
	li {
		line-height: 2;
	}
}

• content内容比较少时，footer就固定在底部
• 多复制几条li，footer就会贴在main的下面
• 通常满屏场景比较多，设置min-height: 100vh

Flex实现

<section class="stick-footer container flex">
	<h2>sticker</h2>
	<main>
		<li>content</li>
	</main>
	<button>footer</button>
</section>

.flex.stick-footer {
	flex-direction: column;
	min-height: 200px;
	main {
		flex: 1 1 auto;
	}
}