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csscss-animationskeyframe

CSS infinite horizontal scroll with keyframe?


As a student, I'm actually making my own portfolio.
For the header, I tried to create a sky effect, with an image scrolling horizontally. I used CSS and keyframes, the problem I have is that when the image come to the end, it "resets" and doesn't continue to scroll smoothly.
Is there any way to make it continue "indefinitely" ? (I changed the duration to 5s just to not make you wait the 40s :p)

@keyframes animatedBackground {
  from { background-position: 0 0; }
  to { background-position: 100% 0; }
}
#header-top {
  height: 190px;
  background-image: url('http://image.noelshack.com/fichiers/2016/46/1479595480-clouds.png');
  background-repeat: repeat-x;
  animation: animatedBackground 5s linear infinite;
  line-height: 400px;

}
<div id="header-top">
</div>

Solution

  • I just cropped your image so the end lines up with the start. Then, I modified the animatedBackground keyframes to end at the opposite end of the image.

    Explanation Image

    Cropped image: Cropped Clouds

    How it works

    @keyframes animatedBackground {
      from {
        left: 0px;
      }
      90% {
        left: -562px;
      }
      100%{left: 0px;}
    }
    #header-top {
      height: 190px;
      width: 562px;
      overflow-x: auto;
      overflow-y: hidden;
    }
    * {
      margin: 0;
      padding: 0;
      font-family:sans-serif;
    }
    .inner-cont {
      width: 1126px;
      position: relative;
      animation: animatedBackground 4s linear infinite;
    }
    img{
      border-right:1px solid black;
      box-sizing:border-box;
    }
    <div id="header-top">
      <div class='inner-cont'>
        <img src="https://archive.org/download/clouds-tiled/clouds-tiled.png" /><img src="https://archive.org/download/clouds-tiled/clouds-tiled.png" />
      </div>
    </div>
    <h3>^ How it actually works(almost) ^</h3>
    <h4>The spinback doesn't actually get animated, but it happens <br/>(The line separates the looped images from each other)</h4>

    Final result

    @keyframes animatedBackground {
      from { background-position: 0px 0; }
      to { background-position: -562px 0; }
    }
    #header-top {
      height: 190px;
      width:100%;
      background-image: url('https://archive.org/download/clouds-tiled/clouds-tiled.png');
      background-repeat: repeat-x;
      animation: animatedBackground 2s linear infinite;
      line-height: 400px;
    
    }
    <div id="header-top">
        </div>