Preventing double borders in CSS Grid

Question

Given the current CSS grid example, how can I collapse the borders in order to avoid the double borders ?

This is such a simple thing to achieve using an Html table. How do I do it using display: grid ?

.wrapper {
  display: grid;
  grid-template-columns: 50px 50px 50px 50px;
}

.wrapper > div {
  padding: 15px;
  text-align: center;
  border: 1px solid black;
}

<div class="wrapper">
  <div>1</div>
  <div>2</div>
  <div>3</div>
  <div>4</div>
  <div>5</div>
  <div>6</div>
  <div>7</div>
  <div>8</div>
</div>

Solution 1

You may do like this :

.wrapper {
  display: inline-grid;
  grid-template-columns: 50px 50px 50px 50px;
  border-bottom: 1px solid black;
  border-left: 1px solid black;
}

.wrapper > div {
  padding: 15px;
  text-align: center;
  border-top: 1px solid black;
  border-right: 1px solid black;
}

body {
 background:pink;
}

<div class="wrapper">
  <div>1</div>
  <div>2</div>
  <div>3</div>
  <div>4</div>
  <div>5</div>
  <div>6</div>
  <div>7</div>
  <div>8</div>
</div>

Another idea is to rely on gradient to fill gaps like below:

.wrapper {
  display: inline-grid;
  grid-template-columns: 50px 50px 50px 50px;
  grid-gap:1px;
  background:
    linear-gradient(#000,#000) center/100% 1px no-repeat,
    repeating-linear-gradient(to right,transparent 0 50px,#000 0 51px);
  border:1px solid;
}

.wrapper > div {
  padding: 15px;
  text-align: center;
}

body {
 background:pink;
}

<div class="wrapper">
  <div>1</div>
  <div>2</div>
  <div>3</div>
  <div>4</div>
  <div>5</div>
  <div>6</div>
  <div>7</div>
  <div>8</div>
</div>

You can also adjust the initial solution to make it more flexible and it will work with any number of items inside a row.

Run the below code on full page and resize the window:

.wrapper {
  display: grid;
  max-width:800px;
  grid-template-columns: repeat(auto-fill,minmax(100px,1fr));
  border-top: 1px solid black;
  border-left: 1px solid black;
}

.wrapper > div {
  padding: 15px;
  text-align: center;
  border-bottom: 1px solid black;
  border-right: 1px solid black;
}

body {
 background:pink;
}

<div class="wrapper">
  <div>1</div>
  <div>2</div>
  <div>3</div>
  <div>4</div>
  <div>5</div>
  <div>6</div>
  <div>7</div>
  <div>8</div>
  <div>9</div>
  <div>10</div>
  <div>11</div>
</div>

Solution 2

Instead of using an actual border around grid items, use the background color on the container (for "border" color) and the grid-gap property (for "border" width).

.wrapper {
  display: inline-grid;
  grid-template-columns: 50px 50px 50px 50px;
  border: 1px solid black;
  grid-gap: 1px;
  background-color: black;
}

.wrapper > div {
  background-color: white;
  padding: 15px;
  text-align: center;
}

<div class="wrapper">
  <div>1</div>
  <div>2</div>
  <div>3</div>
  <div>4</div>
  <div>5</div>
  <div>6</div>
  <div>7</div>
  <div>8</div>
</div>

Solution 3

I found a solution by using the outline property.

.grid {
	width: 100%;
	height: 700px;
	display: grid;
	grid-template-columns: repeat(4, 25fr);
	grid-template-rows: repeat(4, 25fr);
	margin-bottom: 30px;
	grid-gap: 1px;
}

.grid-item {
	background-color: silver;
	outline: 1px solid gray; /* The outline creates the border */
	text-align: center;
	position: relative;
	z-index: 1; /* original z-index */
}

/* If you want to change the color on the hover state */
.grid-item:hover {
	outline: 1px solid red;
	z-index: 2; /* You must apply a z-index bigger than the original z-index or else some parts of the outline will be behind other grid elements */
}

<div class="grid">
  <div class="grid-item"></div>
  <div class="grid-item"></div>
  <div class="grid-item"></div>
  <div class="grid-item"></div>
  <div class="grid-item"></div>
  <div class="grid-item"></div>
  <div class="grid-item"></div>
  <div class="grid-item"></div>
  <div class="grid-item"></div>
  <div class="grid-item"></div>
</div>

Solution 4

.wrapper {
  display: grid;
  grid-template-columns: 50px 50px 50px 50px;
}

.wrapper > div {
  padding: 15px;
  text-align: center;
  border: 1px solid black;
  margin:0 -1px -1px 0;
}

<div class="wrapper">
  <div>1</div>
  <div>2</div>
  <div>3</div>
  <div>4</div>
  <div>5</div>
  <div>6</div>
  <div>7</div>
  <div>8</div>
</div>

margin:0 -1px -1px 0; 

This should do the trick.

Solution 5

There is an easy way to do this:

.grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  grid-gap: 1px;
}

.grid__item {
  border: 1px solid gray;
  box-sizing: content-box;
  width: 100%;
  height: 100%;
}

<div class="grid">
  <div class="grid__item">1</div>
  <div class="grid__item">2</div>
  <div class="grid__item">3</div>
  <div class="grid__item">4</div>
  <div class="grid__item">5</div>
  <div class="grid__item">6</div>
  <div class="grid__item">7</div>
  <div class="grid__item">8</div>
  <div class="grid__item">9</div>
  <div class="grid__item">10</div>
  <div class="grid__item">11</div>
  <div class="grid__item">12</div>
</div>

P.s. The main trick here is in box-sizing: content-box. You don't need it if you do not globally override it with another value. But many people uses border-box, in that case, this override solves the problem with the gap.

View more solutions

Comments

[klugjo]

Kind of hacky but at least it does the trick. Can't believe there isn't an easier way to do this. I might as well build my grid with flexbox ..

[René]

This answer works better with non solid lines and semi-transparant borders. However, cell items are 49px here which can be a bit of nuisance. That's easily fixable.

[Mohammed Joraid]

@pttsky you can change the opacity of the whole div.

[EoghanM]

You just need to add a .grid { grid-gap: 1px; } to fix the superposition of elements.

[GeorgeButter]

It makes more sense if the container has border top, that way if there is only 6 items in the grid the grid won't have a random line.

[Maksim Shamihulau]

It does not work, there are different border widths.

[Onur Arı]

If cells have different border sizes/colors this does not work.

[mfgmicha]

works great if you only want top & bottom border and left & right no border. grid: row-gap: 1px items: box-shadow: 0 1px black, 0 -1px black;

[Hairi]

This is the real asnwer! It even works with wrapping content