Why cannot change checkbox color whatever I do?

You can now simply use the accent-color property :

#cb1 {
  accent-color: #9b59b6;
}

#cb2 {
  accent-color: #34495e;
}

#cb3 {
  accent-color: #e74c3c;
}
<input id="cb1" type="checkbox" checked />
<input id="cb2" type="checkbox" checked />
<input id="cb3" type="checkbox" checked />

Note : as this is a new feature, it is not supported by all browsers, but it is still useful

Here is a compatibility link


Technically, it is possible to change the color of anything with CSS. As mentioned, you can't change the background-color or color but you can use CSS filters. For example:

input[type="checkbox"] { /* change "blue" browser chrome to yellow */
  filter: invert(100%) hue-rotate(18deg) brightness(1.7);
}

If you are really looking for design control over checkboxes though, your best bet is to do the "hidden" checkbox and style an adjacent element such as a div.


Although the question is answered and is older, In exploring some options to overcome the the styling of check boxes issue I encountered this awesome set of CSS3 only styling of check boxes and radio buttons controlling background colors and other appearances. Thought this might be right up the alley of this question.

JSFiddle

body {
    background: #555;
}

h1 {
    color: #eee;
    font: 30px Arial, sans-serif;
    -webkit-font-smoothing: antialiased;
    text-shadow: 0px 1px black;
    text-align: center;
    margin-bottom: 50px;
}

input[type=checkbox] {
    visibility: hidden;
}

/* SLIDE ONE */
.slideOne {
    width: 50px;
    height: 10px;
    background: #333;
    margin: 20px auto;

    -webkit-border-radius: 50px;
    -moz-border-radius: 50px;
    border-radius: 50px;
    position: relative;

    -webkit-box-shadow: inset 0px 1px 1px rgba(0,0,0,0.5), 0px 1px 0px rgba(255,255,255,0.2);
    -moz-box-shadow: inset 0px 1px 1px rgba(0,0,0,0.5), 0px 1px 0px rgba(255,255,255,0.2);
    box-shadow: inset 0px 1px 1px rgba(0,0,0,0.5), 0px 1px 0px rgba(255,255,255,0.2);
}

.slideOne label {
    display: block;
    width: 16px;
    height: 16px;

    -webkit-border-radius: 50px;
    -moz-border-radius: 50px;
    border-radius: 50px;

    -webkit-transition: all .4s ease;
    -moz-transition: all .4s ease;
    -o-transition: all .4s ease;
    -ms-transition: all .4s ease;
    transition: all .4s ease;
    cursor: pointer;
    position: absolute;
    top: -3px;
    left: -3px;

    -webkit-box-shadow: 0px 2px 5px 0px rgba(0,0,0,0.3);
    -moz-box-shadow: 0px 2px 5px 0px rgba(0,0,0,0.3);
    box-shadow: 0px 2px 5px 0px rgba(0,0,0,0.3);
    background: #fcfff4;

    background: -webkit-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: -moz-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: -o-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: -ms-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#fcfff4', endColorstr='#b3bead',GradientType=0 );
}

.slideOne input[type=checkbox]:checked + label {
    left: 37px;
}

/* SLIDE TWO */
.slideTwo {
    width: 80px;
    height: 30px;
    background: #333;
    margin: 20px auto;

    -webkit-border-radius: 50px;
    -moz-border-radius: 50px;
    border-radius: 50px;
    position: relative;

    -webkit-box-shadow: inset 0px 1px 1px rgba(0,0,0,0.5), 0px 1px 0px rgba(255,255,255,0.2);
    -moz-box-shadow: inset 0px 1px 1px rgba(0,0,0,0.5), 0px 1px 0px rgba(255,255,255,0.2);
    box-shadow: inset 0px 1px 1px rgba(0,0,0,0.5), 0px 1px 0px rgba(255,255,255,0.2);
}

.slideTwo:after {
    content: '';
    position: absolute;
    top: 14px;
    left: 14px;
    height: 2px;
    width: 52px;

    -webkit-border-radius: 50px;
    -moz-border-radius: 50px;
    border-radius: 50px;
    background: #111;

    -webkit-box-shadow: inset 0px 1px 1px rgba(0,0,0,0.5), 0px 1px 0px rgba(255,255,255,0.2);
    -moz-box-shadow: inset 0px 1px 1px rgba(0,0,0,0.5), 0px 1px 0px rgba(255,255,255,0.2);
    box-shadow: inset 0px 1px 1px rgba(0,0,0,0.5), 0px 1px 0px rgba(255,255,255,0.2);
}

.slideTwo label {
    display: block;
    width: 22px;
    height: 22px;

    -webkit-border-radius: 50px;
    -moz-border-radius: 50px;
    border-radius: 50px;

    -webkit-transition: all .4s ease;
    -moz-transition: all .4s ease;
    -o-transition: all .4s ease;
    -ms-transition: all .4s ease;
    transition: all .4s ease;
    cursor: pointer;
    position: absolute;
    top: 4px;
    z-index: 1;
    left: 4px;

    -webkit-box-shadow: 0px 2px 5px 0px rgba(0,0,0,0.3);
    -moz-box-shadow: 0px 2px 5px 0px rgba(0,0,0,0.3);
    box-shadow: 0px 2px 5px 0px rgba(0,0,0,0.3);
    background: #fcfff4;

    background: -webkit-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: -moz-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: -o-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: -ms-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#fcfff4', endColorstr='#b3bead',GradientType=0 );
}

.slideTwo label:after {
    content: '';
    position: absolute;
    width: 10px;
    height: 10px;

    -webkit-border-radius: 50px;
    -moz-border-radius: 50px;
    border-radius: 50px;
    background: #333;
    left: 6px;
    top: 6px;

    -webkit-box-shadow: inset 0px 1px 1px rgba(0,0,0,1), 0px 1px 0px rgba(255,255,255,0.9);
    -moz-box-shadow: inset 0px 1px 1px rgba(0,0,0,1), 0px 1px 0px rgba(255,255,255,0.9);
    box-shadow: inset 0px 1px 1px rgba(0,0,0,1), 0px 1px 0px rgba(255,255,255,0.9);
}

.slideTwo input[type=checkbox]:checked + label {
    left: 54px;
}

.slideTwo input[type=checkbox]:checked + label:after {
    background: #00bf00;
}

/* SLIDE THREE */
.slideThree {
    width: 80px;
    height: 26px;
    background: #333;
    margin: 20px auto;

    -webkit-border-radius: 50px;
    -moz-border-radius: 50px;
    border-radius: 50px;
    position: relative;

    -webkit-box-shadow: inset 0px 1px 1px rgba(0,0,0,0.5), 0px 1px 0px rgba(255,255,255,0.2);
    -moz-box-shadow: inset 0px 1px 1px rgba(0,0,0,0.5), 0px 1px 0px rgba(255,255,255,0.2);
    box-shadow: inset 0px 1px 1px rgba(0,0,0,0.5), 0px 1px 0px rgba(255,255,255,0.2);
}

.slideThree:after {
    content: 'OFF';
    font: 12px/26px Arial, sans-serif;
    color: #000;
    position: absolute;
    right: 10px;
    z-index: 0;
    font-weight: bold;
    text-shadow: 1px 1px 0px rgba(255,255,255,.15);
}

.slideThree:before {
    content: 'ON';
    font: 12px/26px Arial, sans-serif;
    color: #00bf00;
    position: absolute;
    left: 10px;
    z-index: 0;
    font-weight: bold;
}

.slideThree label {
    display: block;
    width: 34px;
    height: 20px;

    -webkit-border-radius: 50px;
    -moz-border-radius: 50px;
    border-radius: 50px;

    -webkit-transition: all .4s ease;
    -moz-transition: all .4s ease;
    -o-transition: all .4s ease;
    -ms-transition: all .4s ease;
    transition: all .4s ease;
    cursor: pointer;
    position: absolute;
    top: 3px;
    left: 3px;
    z-index: 1;

    -webkit-box-shadow: 0px 2px 5px 0px rgba(0,0,0,0.3);
    -moz-box-shadow: 0px 2px 5px 0px rgba(0,0,0,0.3);
    box-shadow: 0px 2px 5px 0px rgba(0,0,0,0.3);
    background: #fcfff4;

    background: -webkit-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: -moz-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: -o-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: -ms-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#fcfff4', endColorstr='#b3bead',GradientType=0 );
}

.slideThree input[type=checkbox]:checked + label {
    left: 43px;
}

/* ROUNDED ONE */
.roundedOne {
    width: 28px;
    height: 28px;
    background: #fcfff4;

    background: -webkit-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: -moz-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: -o-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: -ms-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#fcfff4', endColorstr='#b3bead',GradientType=0 );
    margin: 20px auto;

    -webkit-border-radius: 50px;
    -moz-border-radius: 50px;
    border-radius: 50px;

    -webkit-box-shadow: inset 0px 1px 1px white, 0px 1px 3px rgba(0,0,0,0.5);
    -moz-box-shadow: inset 0px 1px 1px white, 0px 1px 3px rgba(0,0,0,0.5);
    box-shadow: inset 0px 1px 1px white, 0px 1px 3px rgba(0,0,0,0.5);
    position: relative;
}

.roundedOne label {
    cursor: pointer;
    position: absolute;
    width: 20px;
    height: 20px;

    -webkit-border-radius: 50px;
    -moz-border-radius: 50px;
    border-radius: 50px;
    left: 4px;
    top: 4px;

    -webkit-box-shadow: inset 0px 1px 1px rgba(0,0,0,0.5), 0px 1px 0px rgba(255,255,255,1);
    -moz-box-shadow: inset 0px 1px 1px rgba(0,0,0,0.5), 0px 1px 0px rgba(255,255,255,1);
    box-shadow: inset 0px 1px 1px rgba(0,0,0,0.5), 0px 1px 0px rgba(255,255,255,1);

    background: -webkit-linear-gradient(top, #222 0%, #45484d 100%);
    background: -moz-linear-gradient(top, #222 0%, #45484d 100%);
    background: -o-linear-gradient(top, #222 0%, #45484d 100%);
    background: -ms-linear-gradient(top, #222 0%, #45484d 100%);
    background: linear-gradient(top, #222 0%, #45484d 100%);
    filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#222', endColorstr='#45484d',GradientType=0 );
}

.roundedOne label:after {
    -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=0)";
    filter: alpha(opacity=0);
    opacity: 0;
    content: '';
    position: absolute;
    width: 16px;
    height: 16px;
    background: #00bf00;

    background: -webkit-linear-gradient(top, #00bf00 0%, #009400 100%);
    background: -moz-linear-gradient(top, #00bf00 0%, #009400 100%);
    background: -o-linear-gradient(top, #00bf00 0%, #009400 100%);
    background: -ms-linear-gradient(top, #00bf00 0%, #009400 100%);
    background: linear-gradient(top, #00bf00 0%, #009400 100%);

    -webkit-border-radius: 50px;
    -moz-border-radius: 50px;
    border-radius: 50px;
    top: 2px;
    left: 2px;

    -webkit-box-shadow: inset 0px 1px 1px white, 0px 1px 3px rgba(0,0,0,0.5);
    -moz-box-shadow: inset 0px 1px 1px white, 0px 1px 3px rgba(0,0,0,0.5);
    box-shadow: inset 0px 1px 1px white, 0px 1px 3px rgba(0,0,0,0.5);
}

.roundedOne label:hover::after {
    -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=30)";
    filter: alpha(opacity=30);
    opacity: 0.3;
}

.roundedOne input[type=checkbox]:checked + label:after {
    -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=100)";
    filter: alpha(opacity=100);
    opacity: 1;
}

/* ROUNDED TWO */
.roundedTwo {
    width: 28px;
    height: 28px;
    background: #fcfff4;

    background: -webkit-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: -moz-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: -o-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: -ms-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#fcfff4', endColorstr='#b3bead',GradientType=0 );
    margin: 20px auto;

    -webkit-border-radius: 50px;
    -moz-border-radius: 50px;
    border-radius: 50px;

    -webkit-box-shadow: inset 0px 1px 1px white, 0px 1px 3px rgba(0,0,0,0.5);
    -moz-box-shadow: inset 0px 1px 1px white, 0px 1px 3px rgba(0,0,0,0.5);
    box-shadow: inset 0px 1px 1px white, 0px 1px 3px rgba(0,0,0,0.5);
    position: relative;
}

.roundedTwo label {
    cursor: pointer;
    position: absolute;
    width: 20px;
    height: 20px;

    -webkit-border-radius: 50px;
    -moz-border-radius: 50px;
    border-radius: 50px;
    left: 4px;
    top: 4px;

    -webkit-box-shadow: inset 0px 1px 1px rgba(0,0,0,0.5), 0px 1px 0px rgba(255,255,255,1);
    -moz-box-shadow: inset 0px 1px 1px rgba(0,0,0,0.5), 0px 1px 0px rgba(255,255,255,1);
    box-shadow: inset 0px 1px 1px rgba(0,0,0,0.5), 0px 1px 0px rgba(255,255,255,1);

    background: -webkit-linear-gradient(top, #222 0%, #45484d 100%);
    background: -moz-linear-gradient(top, #222 0%, #45484d 100%);
    background: -o-linear-gradient(top, #222 0%, #45484d 100%);
    background: -ms-linear-gradient(top, #222 0%, #45484d 100%);
    background: linear-gradient(top, #222 0%, #45484d 100%);
    filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#222', endColorstr='#45484d',GradientType=0 );
}

.roundedTwo label:after {
    -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=0)";
    filter: alpha(opacity=0);
    opacity: 0;
    content: '';
    position: absolute;
    width: 9px;
    height: 5px;
    background: transparent;
    top: 5px;
    left: 4px;
    border: 3px solid #fcfff4;
    border-top: none;
    border-right: none;

    -webkit-transform: rotate(-45deg);
    -moz-transform: rotate(-45deg);
    -o-transform: rotate(-45deg);
    -ms-transform: rotate(-45deg);
    transform: rotate(-45deg);
}

.roundedTwo label:hover::after {
    -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=30)";
    filter: alpha(opacity=30);
    opacity: 0.3;
}

.roundedTwo input[type=checkbox]:checked + label:after {
    -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=100)";
    filter: alpha(opacity=100);
    opacity: 1;
}

/* SQUARED ONE */
.squaredOne {
    width: 28px;
    height: 28px;
    background: #fcfff4;

    background: -webkit-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: -moz-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: -o-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: -ms-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#fcfff4', endColorstr='#b3bead',GradientType=0 );
    margin: 20px auto;
    -webkit-box-shadow: inset 0px 1px 1px white, 0px 1px 3px rgba(0,0,0,0.5);
    -moz-box-shadow: inset 0px 1px 1px white, 0px 1px 3px rgba(0,0,0,0.5);
    box-shadow: inset 0px 1px 1px white, 0px 1px 3px rgba(0,0,0,0.5);
    position: relative;
}

.squaredOne label {
    cursor: pointer;
    position: absolute;
    width: 20px;
    height: 20px;
    left: 4px;
    top: 4px;

    -webkit-box-shadow: inset 0px 1px 1px rgba(0,0,0,0.5), 0px 1px 0px rgba(255,255,255,1);
    -moz-box-shadow: inset 0px 1px 1px rgba(0,0,0,0.5), 0px 1px 0px rgba(255,255,255,1);
    box-shadow: inset 0px 1px 1px rgba(0,0,0,0.5), 0px 1px 0px rgba(255,255,255,1);

    background: -webkit-linear-gradient(top, #222 0%, #45484d 100%);
    background: -moz-linear-gradient(top, #222 0%, #45484d 100%);
    background: -o-linear-gradient(top, #222 0%, #45484d 100%);
    background: -ms-linear-gradient(top, #222 0%, #45484d 100%);
    background: linear-gradient(top, #222 0%, #45484d 100%);
    filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#222', endColorstr='#45484d',GradientType=0 );
}

.squaredOne label:after {
    -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=0)";
    filter: alpha(opacity=0);
    opacity: 0;
    content: '';
    position: absolute;
    width: 16px;
    height: 16px;
    background: #00bf00;

    background: -webkit-linear-gradient(top, #00bf00 0%, #009400 100%);
    background: -moz-linear-gradient(top, #00bf00 0%, #009400 100%);
    background: -o-linear-gradient(top, #00bf00 0%, #009400 100%);
    background: -ms-linear-gradient(top, #00bf00 0%, #009400 100%);
    background: linear-gradient(top, #00bf00 0%, #009400 100%);

    top: 2px;
    left: 2px;

    -webkit-box-shadow: inset 0px 1px 1px white, 0px 1px 3px rgba(0,0,0,0.5);
    -moz-box-shadow: inset 0px 1px 1px white, 0px 1px 3px rgba(0,0,0,0.5);
    box-shadow: inset 0px 1px 1px white, 0px 1px 3px rgba(0,0,0,0.5);
}

.squaredOne label:hover::after {
    -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=30)";
    filter: alpha(opacity=30);
    opacity: 0.3;
}

.squaredOne input[type=checkbox]:checked + label:after {
    -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=100)";
    filter: alpha(opacity=100);
    opacity: 1;
}

/* SQUARED TWO */
.squaredTwo {
    width: 28px;
    height: 28px;
    background: #fcfff4;

    background: -webkit-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: -moz-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: -o-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: -ms-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#fcfff4', endColorstr='#b3bead',GradientType=0 );
    margin: 20px auto;

    -webkit-box-shadow: inset 0px 1px 1px white, 0px 1px 3px rgba(0,0,0,0.5);
    -moz-box-shadow: inset 0px 1px 1px white, 0px 1px 3px rgba(0,0,0,0.5);
    box-shadow: inset 0px 1px 1px white, 0px 1px 3px rgba(0,0,0,0.5);
    position: relative;
}

.squaredTwo label {
    cursor: pointer;
    position: absolute;
    width: 20px;
    height: 20px;
    left: 4px;
    top: 4px;

    -webkit-box-shadow: inset 0px 1px 1px rgba(0,0,0,0.5), 0px 1px 0px rgba(255,255,255,1);
    -moz-box-shadow: inset 0px 1px 1px rgba(0,0,0,0.5), 0px 1px 0px rgba(255,255,255,1);
    box-shadow: inset 0px 1px 1px rgba(0,0,0,0.5), 0px 1px 0px rgba(255,255,255,1);

    background: -webkit-linear-gradient(top, #222 0%, #45484d 100%);
    background: -moz-linear-gradient(top, #222 0%, #45484d 100%);
    background: -o-linear-gradient(top, #222 0%, #45484d 100%);
    background: -ms-linear-gradient(top, #222 0%, #45484d 100%);
    background: linear-gradient(top, #222 0%, #45484d 100%);
    filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#222', endColorstr='#45484d',GradientType=0 );
}

.squaredTwo label:after {
    -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=0)";
    filter: alpha(opacity=0);
    opacity: 0;
    content: '';
    position: absolute;
    width: 9px;
    height: 5px;
    background: transparent;
    top: 4px;
    left: 4px;
    border: 3px solid #fcfff4;
    border-top: none;
    border-right: none;

    -webkit-transform: rotate(-45deg);
    -moz-transform: rotate(-45deg);
    -o-transform: rotate(-45deg);
    -ms-transform: rotate(-45deg);
    transform: rotate(-45deg);
}

.squaredTwo label:hover::after {
    -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=30)";
    filter: alpha(opacity=30);
    opacity: 0.3;
}

.squaredTwo input[type=checkbox]:checked + label:after {
    -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=100)";
    filter: alpha(opacity=100);
    opacity: 1;
}


/* SQUARED THREE */
.squaredThree {
    width: 20px;    
    margin: 20px auto;
    position: relative;
}

.squaredThree label {
    cursor: pointer;
    position: absolute;
    width: 20px;
    height: 20px;
    top: 0;
    border-radius: 4px;

    -webkit-box-shadow: inset 0px 1px 1px rgba(0,0,0,0.5), 0px 1px 0px rgba(255,255,255,.4);
    -moz-box-shadow: inset 0px 1px 1px rgba(0,0,0,0.5), 0px 1px 0px rgba(255,255,255,.4);
    box-shadow: inset 0px 1px 1px rgba(0,0,0,0.5), 0px 1px 0px rgba(255,255,255,.4);

    background: -webkit-linear-gradient(top, #222 0%, #45484d 100%);
    background: -moz-linear-gradient(top, #222 0%, #45484d 100%);
    background: -o-linear-gradient(top, #222 0%, #45484d 100%);
    background: -ms-linear-gradient(top, #222 0%, #45484d 100%);
    background: linear-gradient(top, #222 0%, #45484d 100%);
    filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#222', endColorstr='#45484d',GradientType=0 );
}

.squaredThree label:after {
    -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=0)";
    filter: alpha(opacity=0);
    opacity: 0;
    content: '';
    position: absolute;
    width: 9px;
    height: 5px;
    background: transparent;
    top: 4px;
    left: 4px;
    border: 3px solid #fcfff4;
    border-top: none;
    border-right: none;

    -webkit-transform: rotate(-45deg);
    -moz-transform: rotate(-45deg);
    -o-transform: rotate(-45deg);
    -ms-transform: rotate(-45deg);
    transform: rotate(-45deg);
}

.squaredThree label:hover::after {
    -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=30)";
    filter: alpha(opacity=30);
    opacity: 0.3;
}

.squaredThree input[type=checkbox]:checked + label:after {
    -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=100)";
    filter: alpha(opacity=100);
    opacity: 1;
}

/* SQUARED FOUR */
.squaredFour {
    width: 20px;    
    margin: 20px auto;
    position: relative;
}

.squaredFour label {
    cursor: pointer;
    position: absolute;
    width: 20px;
    height: 20px;
    top: 0;
    border-radius: 4px;

    -webkit-box-shadow: inset 0px 1px 1px white, 0px 1px 3px rgba(0,0,0,0.5);
    -moz-box-shadow: inset 0px 1px 1px white, 0px 1px 3px rgba(0,0,0,0.5);
    box-shadow: inset 0px 1px 1px white, 0px 1px 3px rgba(0,0,0,0.5);
    background: #fcfff4;

    background: -webkit-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: -moz-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: -o-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: -ms-linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    background: linear-gradient(top, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%);
    filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#fcfff4', endColorstr='#b3bead',GradientType=0 );
}

.squaredFour label:after {
    -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=0)";
    filter: alpha(opacity=0);
    opacity: 0;
    content: '';
    position: absolute;
    width: 9px;
    height: 5px;
    background: transparent;
    top: 4px;
    left: 4px;
    border: 3px solid #333;
    border-top: none;
    border-right: none;

    -webkit-transform: rotate(-45deg);
    -moz-transform: rotate(-45deg);
    -o-transform: rotate(-45deg);
    -ms-transform: rotate(-45deg);
    transform: rotate(-45deg);
}

.squaredFour label:hover::after {
    -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=30)";
    filter: alpha(opacity=30);
    opacity: 0.5;
}

.squaredFour input[type=checkbox]:checked + label:after {
    -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=100)";
    filter: alpha(opacity=100);
    opacity: 1;
}
<h1>CSS3 Checkbox Styles</h1>

<!-- Slide ONE -->
<div class="slideOne">  
    <input type="checkbox" value="None" id="slideOne" name="check" />
    <label for="slideOne"></label>
</div>

<!-- Slide TWO -->
<div class="slideTwo">  
    <input type="checkbox" value="None" id="slideTwo" name="check" />
    <label for="slideTwo"></label>
</div>

<!-- Slide THREE -->
<div class="slideThree">    
    <input type="checkbox" value="None" id="slideThree" name="check" />
    <label for="slideThree"></label>
</div>

<!-- Rounded ONE -->
<div class="roundedOne">
    <input type="checkbox" value="None" id="roundedOne" name="check" />
    <label for="roundedOne"></label>
</div>

<!-- Rounded TWO -->
<div class="roundedTwo">
    <input type="checkbox" value="None" id="roundedTwo" name="check" />
    <label for="roundedTwo"></label>
</div>

<!-- Squared ONE -->
<div class="squaredOne">
    <input type="checkbox" value="None" id="squaredOne" name="check" />
    <label for="squaredOne"></label>
</div>

<!-- Squared TWO -->
<div class="squaredTwo">
    <input type="checkbox" value="None" id="squaredTwo" name="check" />
    <label for="squaredTwo"></label>
</div>

<!-- Squared THREE -->
<div class="squaredThree">
    <input type="checkbox" value="None" id="squaredThree" name="check" />
    <label for="squaredThree"></label>
</div>

<!-- Squared FOUR -->
<div class="squaredFour">
    <input type="checkbox" value="None" id="squaredFour" name="check" />
    <label for="squaredFour"></label>
</div>