双边界div应合并css

Question

如果你看这个小提琴,你会发现边框不会合并.
CSS:

div{
    float:left;
    background-color:moccasin;
    width:100px;
    height:100px;
    border:1px solid tomato;
}

div的数量是随机的,我只能给它1个class/id.
另请注意,页面可以调整大小,并且行上的div数量可以更改.

我已经尝试过margin-left:1px;last-child/nth-child()选择器,但是当你调整屏幕大小时它们不起作用,或者它仍然会产生不需要的边框.

编辑:我不能移动单个像素的div,当我给div margin-left:-1px;并给出第一个div时,margin-left:1px;我将在下一行中得到不需要的结果.

Answer 1

只需添加到div

margin-top: -1px;
margin-left: -1px;

检查以下示例:

div{
    float:left;
    background-color:moccasin;
    width:100px;
    height:100px;
    border:1px solid tomato;
    margin-left: -1px;
    margin-top: -1px;
}

<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>

JS的另一个解决方案 这是DEMO

CSS:

div{
float:left;
background-color:moccasin;
width:100px;
height:100px;    
border-bottom:1px solid tomato;
border-right:1px solid tomato;
}
div:first-child{
border-left:1px solid tomato;
}
div.first-row {
border-top: 1px solid tomato;
}

jQuery的:

var borderCollapse = function() {
var div = $('div');
var divWidth = 0;
var rows = 1;
div.each(function() {
var that = $(this);
var div = $('div');
var width = div.parent().width();
var thisWidth = $(this).width();

if (divWidth < width) {    
    that.prev().not('div:first-child').css({'border-left':'0'});
    divWidth += parseInt(thisWidth);        
} else { 
    that.prev().css({'border-left':'1px solid tomato'});
    divWidth = 2 * thisWidth;
    rows += 1;        
}

if (rows <= 1) {
    that.prev().addClass('first-row');
} else {
    that.prev().removeClass('first-row');
}

});
}

borderCollapse();

$(window).resize(function() {
  borderCollapse();
});

Answer 2

我们可以模拟折叠边框box-shadow: 0 0 0 1px tomato 而不是边框; 添加1px左下边距以正确对齐.

这是因为盒子阴影自然重叠; 它不会占用空间.我们只显示左边距和下边距所需的阴影量.

1px"边框"

div {
  float: left;
  background-color: moccasin;
  width: 100px;
  height: 100px;
  box-shadow: 0 0 0 1px tomato;
  margin: 0 0 1px 1px; 
 /* the margin provides a little nudge as 
 box shadow won't take up space like a border 
 */
}

<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>

带有5px"边框"

div {
  float: left;
  background-color: moccasin;
  width: 100px;
  height: 100px;
  box-shadow: 0 0 0 5px tomato;
  margin: 0 0 5px 5px; 
 /* the margin provides a little nudge as 
 box shadow won't take up space like a border 
 */
}

<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>