CSS responsive grid of squares

Media queries for a responsive grid of squares with equal space between squares and window.

by Kirubel Girma

HTML

<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>

CSS

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;
    }
}