Left aligned last row in centered grid of elements

Solution 1:

Solution with display inline-block

This adaptive grid is much simpler : less markup and less CSS so it will be easier to implement in a production site and adapt to your exact needs.

=>> DEMO <<= (resize the result window to see the effect)

html, body {
    margin:0;
    padding:0;
}
#container{
    font-size:0;
    margin:0 auto;
    width:1000px;
}
.block {
    font-size:20px;
    width: 150px;
    height: 150px;
    margin:25px;
    background: gold;
    display:inline-block;
}

@media screen and (max-width: 430px) {
    #container{
        width:200px;
    }
}

@media screen and (min-width: 431px) and (max-width: 630px) {
   #container{
        width:400px;
    }
}
@media screen and (min-width: 631px) and (max-width: 830px) {
   #container{
        width:600px;
    }
}
@media screen and (min-width: 831px) and (max-width: 1030px) {
   #container{
        width:800px;
    }
}

<div id="container">
    <div class="block">1</div>
    <div class="block">2</div>
    <div class="block">3</div>
    <div class="block">4</div>
    <div class="block">5</div>
    <div class="block">6</div>
    <div class="block">7</div>
    <div class="block">8</div>
    <div class="block">9</div>
    <div class="block">10</div>
    <div class="block">11</div>
    <div class="block">12</div>
    <div class="block">13</div>
</div>

It involves :

4 media queries for 200px wide blocks and a container expandable to 1000px. Depending on the width of your grid elements and the total width of your container you may have to make less or more
removing white-spaces between inline-block elements (in the following demo I used the font-size technique but you can use other ones (see How to remove the space between inline-block elements? for other techniques)
fixed margins between blocks

The number of blocks in one line adapts to the size of the container. The text-align property stay to default value left so the last items are aligned to the left.

Floats with adaptive margins between both blocks and container

=>> DEMO <<= (you need to resize the result window under 750px to see it in action)

html, body {
    margin:0;
    padding:0;
    min-width:150px;
}
.wrap {
    float:left;
    position:relative;
}
.foto {
    width: 150px;
    height: 150px;
    background: gold;
    position:absolute;
}

#warning{display:none;}
@media screen and (min-width: 631px) {
    .wrap {
        width:20%;
        padding-bottom:25%;
    }
    .wrap:nth-child(4n+2), .wrap:nth-child(4n+3){
        
    }
    .wrap .foto {
        top:-75px;
        margin-top:100%;
        right:-30px;
    }
    .wrap:nth-child(4n+2){
        margin:0 5% 0 7.5%;
    }
    .wrap:nth-child(4n+3){
     margin-right:7.5%;
    }
    .wrap:nth-child(4n+2) .foto{
        left:50%;
        margin-left:-75px;
    }
    .wrap:nth-child(4n+3) .foto{
        right:50%;
        margin-right:-75px;
    }
    .wrap:nth-child(4n) .foto{
        left:-30px;
    }   
    #container{
        margin-top:-45px;
    }
}

@media screen and (min-width: 481px) and (max-width: 631px) {
    .wrap {
        width:25%;
        padding-bottom:33.3%;
    }
    .wrap:nth-child(3n+2){
        margin:0 12.5%;        
    }
    .wrap .foto {
        top:-75px;
        margin-top:100%;
        right:-37px;
    }
     .wrap:nth-child(3n+2) .foto{
        left:50%;
        margin-left:-75px;
    }
     .wrap:nth-child(3n) .foto{
        left:-37px;
    }
    #container{
        margin-top:-37px;
    }
}


@media screen and (min-width: 331px) and (max-width: 480px) {
    .wrap {
        width:33.3%;
        padding-bottom:50%;
        clear:left;
    }
    .wrap:nth-child(even) {
        float:right;
        clear:right;
    }
    .wrap .foto {
        top:-75px;
        margin-top:100%;
        right:-50px;
    }
    .wrap:nth-child(even) .foto {
        left:-50px;
    }
    .wrap:nth-child(4n+3) .foto, .wrap:nth-child(4n+4) .foto {
        bottom:-75px;
        margin-bottom:100%;
    }
    #container{
        margin-top:-25px;
    }
}


@media screen and (max-width: 330px) {
    .wrap {
        width:50%;
        padding-bottom:100%;
        clear:left;
    }
    .wrap:nth-child(odd) .foto {
        right:-75px;
        bottom:0;
        bottom:-75px;
        margin-bottom:100%;
    }
    .wrap:nth-child(even) .foto {
        top:0px;
        right:-75px;
        top:-75px;
        margin-top:100%;
    }
}

@media screen and (min-width: 751px) {
    #warning{
        color:#fff;
        display:block;
        position:fixed;
        width:100%;
        height:50%;
        top:25%;
        left:0;
        background:#000;
        text-align:center;
        font-size:30px;
}

<div id="container">
    <div class="wrap"><div class="foto">1</div></div>
    <div class="wrap"><div class="foto">2</div></div>
    <div class="wrap"><div class="foto">3</div></div>
    <div class="wrap"><div class="foto">4</div></div>
    <div class="wrap"><div class="foto">5</div></div>
    <div class="wrap"><div class="foto">6</div></div>
    <div class="wrap"><div class="foto">7</div></div>
    <div class="wrap"><div class="foto">8</div></div>
    <div class="wrap"><div class="foto">9</div></div>
    <div class="wrap"><div class="foto">10</div></div>
    <div class="wrap"><div class="foto">11</div></div>
    <div class="wrap"><div class="foto">12</div></div>
    <div class="wrap"><div class="foto">13</div></div>
    <div class="wrap"><div class="foto">14</div></div>
    <div class="wrap"><div class="foto">15</div></div>
</div>

<!-- FOLLOWING JUST FOR THE DEMO -->
<div id="warning">I haven't written the code for windows bigger than 751px.<br/>
    You must resize this window under 751px.</div>

This technique involves :

floats
position:absolute;
:nt-child() css selector
media queries

It centers the blocks in their container and gives the same margin on the top/left/tight/bottom of all the blocks + sides of the container. As this solution uses floats, the last row is aligned to the left.

The number of blocks in one line adapts to the width of the window.

Solution 2:

Here's a very simple JavaScript (and some small changes in your CSS) solution for you:

http://jsfiddle.net/ha68t/

It's working fine for me.

CSS:

.container {
  margin: 0 auto;
  max-width:960px;
  background-color: gold;
}

.block {
  background-color: #ddd;
  border:1px solid #999;
  display: block;
  float: left;
  height: 100px;
  margin: 4px 2px;
  width: 100px;
}

JavaScript:

$(document).ready(function(){
    setContainerWidth();
});

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

function setContainerWidth()
{
    $('.container').css('width', 'auto'); //reset
    var windowWidth = $(document).width();
    var blockWidth = $('.block').outerWidth(true);
    var maxBoxPerRow = Math.floor(windowWidth / blockWidth);
    $('.container').width(maxBoxPerRow * blockWidth);
}

jQuery is required :)

Solution 3:

For what it's worth: It's now 2017 and the grid layout module does this out of the box

* {
    margin:0;
    padding:0;
}

.container {
  display: grid;
  grid-template-columns: repeat(auto-fill, 100px);
  grid-gap: 10px;
  justify-content: center;
  align-content: flex-start;
  margin: 0 auto;
  text-align: center;
  margin-top: 10px;
}
.block {
  background-color: #ddd;
  border: 1px solid #999;
  height: 100px;
  width: 100px;
}

<div class="container">
  <div class="block">Foo</div>
  <div class="block">Foo</div>
  <div class="block">Foo</div>
  <div class="block">Foo</div>
  <div class="block">Foo</div>
  <div class="block">Foo</div>
  <div class="block">Foo</div>
  <div class="block">Foo</div>
  <div class="block">Foo</div>
  <div class="block">Foo</div>
  <div class="block">Foo</div>
  <div class="block">Foo</div>
  <div class="block">Foo</div>
  <div class="block">Foo</div>
  <div class="block">Foo</div>
  <div class="block">Foo</div>
  <div class="block">Foo</div>
  <div class="block">Foo</div>
  <div class="block">Foo</div>
  <div class="block">Foo</div>
  <div class="block">Foo</div>
  <div class="block">Foo</div>
  <div class="block">Foo</div>
</div>

(Codepen demo).

If the browser support suits you - then use grid. If not, then read on....

As mentioned in @Web-tiki's answer, the best you can do with CSS is with a series of media queries.

That being said, if you are using a preprocessor such as LESS - this isn't such a difficult or error-prone task. (although, yes, the CSS will still be long and ugly)

UPDATED CODEPEN (Resize the window to see the results)

Here's how to take advantage of LESS to set up the media queries:

First set up some less variables according to the design which you need:

@item-width:100px;
@item-height:100px;
@marginV: 4px;
@marginH: 2px;
@min-cols:2;
@max-cols:9; //set an upper limit of how may columns you want to write the media queries for

Then:

Set up an iteration mixin like this: (You can paste this code into http://less2css.org)

.loopingClass (@index-width) when (@index-width <= @item-width * @max-cols) {
    @media (min-width:@index-width) {
        .container{
            width: @index-width;
        }
    }

    .loopingClass(@index-width + @item-width + 2*@marginH);
}

.loopingClass (@item-width * @min-cols + @min-cols*@marginH*2);

The above mixin will spit out a series of media queries in the form:

@media (min-width: 208px) {
  .container {
    width: 208px;
  }
}
@media (min-width: 312px) {
  .container {
    width: 312px;
  }
}
@media (min-width: 416px) {
  .container {
    width: 416px;
  }
}
@media (min-width: 520px) {
  .container {
    width: 520px;
  }
}
@media (min-width: 624px) {
  .container {
    width: 624px;
  }
}
@media (min-width: 728px) {
  .container {
    width: 728px;
  }
}
@media (min-width: 832px) {
  .container {
    width: 832px;
  }
}

With remaining CSS (LESS):

.container {
  margin: 0 auto;
  text-align: center;
  overflow: auto;
    min-width: @min-cols * @item-width;
    max-width: @max-cols * @item-width;
    display: block;
    list-style:none;
}
.block {
  background-color: #ddd;
  border:1px solid #999;
  box-sizing:border-box;
  float: left;
  height: @item-height;
  width: @item-width;
  margin:@marginV @marginH;
}

... you get the desired result.

...and it's super easy to customize the layout:

All I need to do is change the variables that I used in the LESS mixin according to my needs - I get the exact layout that I'm after.

Solution 4:

With flexbox, some pseudo elements, an extra div, and after a lot of frustration I was able to achieve this without media queries (since I needed to put my grid inside many different sized elements, media queries wouldn't really work for me).

One caveat: gutters between items are fluid.

Demo: http://codepen.io/anon/pen/OXvxEW

CSS:

.wrapper {
    display: flex;
    flex-wrap: wrap;
    border: 2px solid #ffc0cb;
    max-width: 1100px;
    margin: 0.5rem auto;
    justify-content: center;
}

.wrapper:after {
    content: ' ';
    flex: 1;
    height: 100%;
    border: 1px solid #00f;
    margin: 0.5rem;
}

.child {
    flex: 1;
    border: 2px solid #ffa500;
    min-width: 300px;
    margin: 0.5rem;
    text-align: center;
}

.child-contents {
    width: 300px;
    border: 2px solid #008000;
    height: 100px;
    margin: 0 auto;
}

HTML:

<div class='wrapper'>
    <div class='child'>
        <div class='child-contents'></div>
    </div>
    <div class='child'>
        <div class='child-contents'></div>
    </div>
    <div class='child'>
        <div class='child-contents'></div>
    </div>

    ...etc., more .child's...

</div>

The end result is something like this, where the green rectangles are divs. The pink/orange borders are just for reference so you can see what's going on. If you remove the pink/orange borders, you should get the grid you're looking for (though again, note that the gutter are fluid).

enter image description here