[html] How can apply multiple background color to one div

The A div can actually be made without :before or :after selector but using linear gradient as your first try. The only difference is that you must specify 4 positions. Dark grey from 0 to 50% and ligth grey from 50% to 100% like this:

background: linear-gradient(to right,  #9c9e9f 0%,#9c9e9f 50%,#f6f6f6 50%,#f6f6f6 100%);

As you know, B div is made from a linear gradient having 2 positions like this:

background: linear-gradient(to right,  #9c9e9f 0%,#f6f6f6 100%);

For the C div, i use the same kind of gradient as div A ike this:

background: linear-gradient(to right,  #9c9e9f 0%,#9c9e9f 50%,#33ccff 50%,#33ccff 100%);

But this time i used the :after selector with a white background like if the second part of your div was smaller. * Please note that I added a better alternative below.

Check this jsfiddle or the snippet below for complete cross-browser code.

_x000D_
_x000D_
div{_x000D_
    position:relative;_x000D_
    width:80%;_x000D_
    height:100px;_x000D_
    color:red;_x000D_
    text-align:center;_x000D_
    line-height:100px;_x000D_
    margin-bottom:10px;_x000D_
}_x000D_
_x000D_
.a{_x000D_
    background: #9c9e9f; /* Old browsers */_x000D_
    background: -moz-linear-gradient(left,  #9c9e9f 0%, #9c9e9f 50%, #f6f6f6 50%, #f6f6f6 100%); /* FF3.6+ */_x000D_
    background: -webkit-gradient(linear, left top, right top, color-stop(0%,#9c9e9f), color-stop(50%,#9c9e9f), color-stop(50%,#f6f6f6), color-stop(100%,#f6f6f6)); /* Chrome,Safari4+ */_x000D_
    background: -webkit-linear-gradient(left,  #9c9e9f 0%,#9c9e9f 50%,#f6f6f6 50%,#f6f6f6 100%); /* Chrome10+,Safari5.1+ */_x000D_
    background: -o-linear-gradient(left,  #9c9e9f 0%,#9c9e9f 50%,#f6f6f6 50%,#f6f6f6 100%); /* Opera 11.10+ */_x000D_
    background: -ms-linear-gradient(left,  #9c9e9f 0%,#9c9e9f 50%,#f6f6f6 50%,#f6f6f6 100%); /* IE10+ */_x000D_
    background: linear-gradient(to right,  #9c9e9f 0%,#9c9e9f 50%,#f6f6f6 50%,#f6f6f6 100%); /* W3C */_x000D_
    filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#9c9e9f', endColorstr='#f6f6f6',GradientType=1 ); /* IE6-9 */_x000D_
}_x000D_
_x000D_
.b{_x000D_
    background: #9c9e9f; /* Old browsers */_x000D_
    background: -moz-linear-gradient(left,  #9c9e9f 0%, #f6f6f6 100%); /* FF3.6+ */_x000D_
    background: -webkit-gradient(linear, left top, right top, color-stop(0%,#9c9e9f), color-stop(100%,#f6f6f6)); /* Chrome,Safari4+ */_x000D_
    background: -webkit-linear-gradient(left,  #9c9e9f 0%,#f6f6f6 100%); /* Chrome10+,Safari5.1+ */_x000D_
    background: -o-linear-gradient(left,  #9c9e9f 0%,#f6f6f6 100%); /* Opera 11.10+ */_x000D_
    background: -ms-linear-gradient(left,  #9c9e9f 0%,#f6f6f6 100%); /* IE10+ */_x000D_
    background: linear-gradient(to right,  #9c9e9f 0%,#f6f6f6 100%); /* W3C */_x000D_
    filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#9c9e9f', endColorstr='#f6f6f6',GradientType=1 ); /* IE6-9 */_x000D_
}_x000D_
_x000D_
.c{    _x000D_
    background: #9c9e9f; /* Old browsers */_x000D_
    background: -moz-linear-gradient(left,  #9c9e9f 0%, #9c9e9f 50%, #33ccff 50%, #33ccff 100%); /* FF3.6+ */_x000D_
    background: -webkit-gradient(linear, left top, right top, color-stop(0%,#9c9e9f), color-stop(50%,#9c9e9f), color-stop(50%,#33ccff), color-stop(100%,#33ccff)); /* Chrome,Safari4+ */_x000D_
    background: -webkit-linear-gradient(left,  #9c9e9f 0%,#9c9e9f 50%,#33ccff 50%,#33ccff 100%); /* Chrome10+,Safari5.1+ */_x000D_
    background: -o-linear-gradient(left,  #9c9e9f 0%,#9c9e9f 50%,#33ccff 50%,#33ccff 100%); /* Opera 11.10+ */_x000D_
    background: -ms-linear-gradient(left,  #9c9e9f 0%,#9c9e9f 50%,#33ccff 50%,#33ccff 100%); /* IE10+ */_x000D_
    background: linear-gradient(to right,  #9c9e9f 0%,#9c9e9f 50%,#33ccff 50%,#33ccff 100%); /* W3C */_x000D_
    filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#9c9e9f', endColorstr='#33ccff',GradientType=1 ); /* IE6-9 */_x000D_
}_x000D_
.c:after{_x000D_
    content:"";_x000D_
    position:absolute;_x000D_
    right:0;_x000D_
    bottom:0;_x000D_
    width:50%;_x000D_
    height:20%;_x000D_
    background-color:white;_x000D_
}
_x000D_
<div class="a">A</div>_x000D_
<div class="b">B</div>_x000D_
<div class="c">C</div>
_x000D_
_x000D_
_x000D_


There is also an alternative for the C div without using a white background to hide the a part of the second section. Instead, we make the second part transparent and we use the :after selector to act as a colored background with the desired position and size.

See this jsfiddle or the snippet below for this updated solution.

_x000D_
_x000D_
div {_x000D_
  position: relative;_x000D_
  width: 80%;_x000D_
  height: 100px;_x000D_
  color: red;_x000D_
  text-align: center;_x000D_
  line-height: 100px;_x000D_
  margin-bottom: 10px;_x000D_
}_x000D_
_x000D_
.a {_x000D_
  background: #9c9e9f;_x000D_
  /* Old browsers */_x000D_
  background: -moz-linear-gradient(left, #9c9e9f 0%, #9c9e9f 50%, #f6f6f6 50%, #f6f6f6 100%);_x000D_
  /* FF3.6+ */_x000D_
  background: -webkit-gradient(linear, left top, right top, color-stop(0%, #9c9e9f), color-stop(50%, #9c9e9f), color-stop(50%, #f6f6f6), color-stop(100%, #f6f6f6));_x000D_
  /* Chrome,Safari4+ */_x000D_
  background: -webkit-linear-gradient(left, #9c9e9f 0%, #9c9e9f 50%, #f6f6f6 50%, #f6f6f6 100%);_x000D_
  /* Chrome10+,Safari5.1+ */_x000D_
  background: -o-linear-gradient(left, #9c9e9f 0%, #9c9e9f 50%, #f6f6f6 50%, #f6f6f6 100%);_x000D_
  /* Opera 11.10+ */_x000D_
  background: -ms-linear-gradient(left, #9c9e9f 0%, #9c9e9f 50%, #f6f6f6 50%, #f6f6f6 100%);_x000D_
  /* IE10+ */_x000D_
  background: linear-gradient(to right, #9c9e9f 0%, #9c9e9f 50%, #f6f6f6 50%, #f6f6f6 100%);_x000D_
  /* W3C */_x000D_
  filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#9c9e9f', endColorstr='#f6f6f6', GradientType=1);_x000D_
  /* IE6-9 */_x000D_
}_x000D_
_x000D_
.b {_x000D_
  background: #9c9e9f;_x000D_
  /* Old browsers */_x000D_
  background: -moz-linear-gradient(left, #9c9e9f 0%, #f6f6f6 100%);_x000D_
  /* FF3.6+ */_x000D_
  background: -webkit-gradient(linear, left top, right top, color-stop(0%, #9c9e9f), color-stop(100%, #f6f6f6));_x000D_
  /* Chrome,Safari4+ */_x000D_
  background: -webkit-linear-gradient(left, #9c9e9f 0%, #f6f6f6 100%);_x000D_
  /* Chrome10+,Safari5.1+ */_x000D_
  background: -o-linear-gradient(left, #9c9e9f 0%, #f6f6f6 100%);_x000D_
  /* Opera 11.10+ */_x000D_
  background: -ms-linear-gradient(left, #9c9e9f 0%, #f6f6f6 100%);_x000D_
  /* IE10+ */_x000D_
  background: linear-gradient(to right, #9c9e9f 0%, #f6f6f6 100%);_x000D_
  /* W3C */_x000D_
  filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#9c9e9f', endColorstr='#f6f6f6', GradientType=1);_x000D_
  /* IE6-9 */_x000D_
}_x000D_
_x000D_
.c {_x000D_
  background: #9c9e9f;_x000D_
  /* Old browsers */_x000D_
  background: -moz-linear-gradient(left, #9c9e9f 0%, #9c9e9f 50%, rgba(0, 0, 0, 0) 50%, rgba(0, 0, 0, 0) 100%);_x000D_
  /* FF3.6+ */_x000D_
  background: -webkit-gradient(linear, left top, right top, color-stop(0%, #9c9e9f), color-stop(50%, #9c9e9f), color-stop(50%, rgba(0, 0, 0, 0)), color-stop(100%, rgba(0, 0, 0, 0)));_x000D_
  /* Chrome,Safari4+ */_x000D_
  background: -webkit-linear-gradient(left, #9c9e9f 0%, #9c9e9f 50%, rgba(0, 0, 0, 0) 50%, rgba(0, 0, 0, 0) 100%);_x000D_
  /* Chrome10+,Safari5.1+ */_x000D_
  background: -o-linear-gradient(left, #9c9e9f 0%, #9c9e9f 50%, rgba(0, 0, 0, 0) 50%, rgba(0, 0, 0, 0) 100%);_x000D_
  /* Opera 11.10+ */_x000D_
  background: -ms-linear-gradient(left, #9c9e9f 0%, #9c9e9f 50%, rgba(0, 0, 0, 0) 50%, rgba(0, 0, 0, 0) 100%);_x000D_
  /* IE10+ */_x000D_
  background: linear-gradient(to right, #9c9e9f 0%, #9c9e9f 50%, rgba(0, 0, 0, 0) 50%, rgba(0, 0, 0, 0) 100%);_x000D_
  /* W3C */_x000D_
  filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#9c9e9f', endColorstr='#ffffff00', GradientType=1);_x000D_
  /* IE6-9 */_x000D_
}_x000D_
_x000D_
.c:after {_x000D_
  content: "";_x000D_
  position: absolute;_x000D_
  right: 0;_x000D_
  top: 0;_x000D_
  width: 50%;_x000D_
  height: 80%;_x000D_
  background-color: #33ccff;_x000D_
  z-index: -1_x000D_
}
_x000D_
<div class="a">A</div>_x000D_
<div class="b">B</div>_x000D_
<div class="c">C</div>
_x000D_
_x000D_
_x000D_