one sided skew with css

Question

I want to create a one sided skew, but failed to do so. here is what I've tried so far:

    .bg-style1 {
      background: #ccc;
      position: relative;
      display: block;
      z-index: 2;
    }
    .bg-style1:after {
      content: " ";
      position: absolute;
      display: block;
      width: 30%;
      height: 100%;
      top: 0;
      left: 0;
      z-index: -1;
      background: #333333;
      -ms-transform: skew(-30deg, 0deg);
      -webkit-transform: skew(-30deg, 0deg);
      transform: skew(-30deg, 0deg);
    }

<section class="page">
  <div class="bg-style1">
    .....content goes here
  </div>
</section>

but it is not working. look:

what I want to accomplish:

Answer 1

Is your problem because of parents background showing up at the left of skewed block. If yes then you should use transform-origin: 0 0;

    .bg-style1 {
      background: #ccc;
      position: relative;
      display: block;
      z-index: 2;
    }
    .bg-style1:after {
      content: " ";
      position: absolute;
      display: block;
      width: 30%;
      height: 100%;
      top: 0;
      left: 0;
      z-index: -1;
      background: #333333;
      -ms-transform: skew(-30deg, 0deg);
      -webkit-transform: skew(-30deg, 0deg);
      transform: skew(-30deg, 0deg);
      transform-origin: 0 0;
    }

<section class="page">
  <div class="bg-style1">
    .....content goes here
  </div>
</section>

Answer 2

Add overflow:hidden to your .bg-style1 rule and transformX(-40%) to the transform: in .bg-style1:after

.bg-style1 {
  padding-top: ;
  background: #ccc;
  position: relative;
  display: block;
  z-index: 2;
  overflow: hidden;
}
.bg-style1:after {
  content: " ";
  position: absolute;
  display: block;
  width: 30%;
  height: 100%;
  left: 0;
  top: 0;
  z-index: -1;
  background: #333333;
  -ms-transform: skew(-30deg, 0deg);
  -webkit-transform: skew(-30deg, 0deg);
  transform: skew(-30deg, 0deg) translateX(-50%);
}

<section class="page">
  <div class="bg-style1">
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  </div>
</section>