Positioning divs with 100vh

Question

In this code I have two div elements saved, and each of them is set on the entire length of the page (100vh), but instead of being one above the other, as if I wanted to overlap. Part of the problem is solved instead of "absolute" in particles-js I put "static" then they do not overlap each other, but animated particles are imposed on div with Content

HTML

<div id="particles-js">
</div>

<div class="content">
<h1>Content</h1>
</div>

<script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/jquery/2.1.3/jquery.min.js"></script>
<script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/particles.js/2.0.0/particles.min.js"></script>

CSS

#particles-js {
  position: absolute;
    width: 100%;
    height: 100vh;
    z-index: -1;
  background-color: #222;
  background-repeat: no-repeat;
  background-size: cover;
  background-position: 50% 50%;
}


canvas{
    position: absolute;
    width: 100%;
    height: 500px;
    z-index: -1;
}

.content
{
  position: relative;
    height: 100vh;
    background-color: #F4F7F5;
    color: #222222;
  }

and JS

particlesJS("particles-js", 
{
  "particles": {
    "number": {
      "value": 50,
      "density": {
        "enable": true,
        "value_area": 800
      }
    },
    "color": {
      "value": "#ffffff"
    },
    "shape": {
      "type": "circle",
      "stroke": {
        "width": 0,
        "color": "#000000"
      },
      "polygon": {
        "nb_sides": 5
      },
      "image": {
        "src": "img/github.svg",
        "width": 100,
        "height": 100
      }
    },
    "opacity": {
      "value": 0.5,
      "random": false,
      "anim": {
        "enable": false,
        "speed": 1,
        "opacity_min": 0.1,
        "sync": false
      }
    },
    "size": {
      "value": 3,
      "random": true,
      "anim": {
        "enable": false,
        "speed": 40,
        "size_min": 0.1,
        "sync": false
      }
    },
    "line_linked": {
      "enable": true,
      "distance": 150,
      "color": "#ffffff",
      "opacity": 0.4,
      "width": 1
    },
    "move": {
      "enable": true,
      "speed": 3,
      "direction": "none",
      "random": false,
      "straight": false,
      "out_mode": "out",
      "bounce": false,
      "attract": {
        "enable": false,
        "rotateX": 600,
        "rotateY": 1200
      }
    }
  },
  "interactivity": {
    "detect_on": "canvas",
    "events": {
      "onhover": {
        "enable": false,
        "mode": "repulse"
      },
      "onclick": {
        "enable": false,
        "mode": "push"
      },
      "resize": true
    },
    "modes": {
      "grab": {
        "distance": 527.4388051113614,
        "line_linked": {
          "opacity": 1
        }
      },
      "bubble": {
        "distance": 599.3622785356379,
        "size": 63.93197637713472,
        "duration": 5.354303021585032,
        "opacity": 0.30367688779138985,
        "speed": 3
      },
      "repulse": {
        "distance": 271.7108996028225,
        "duration": 0.4
      },
      "push": {
        "particles_nb": 4
      },
      "remove": {
        "particles_nb": 2
      }
    }
  },
  "retina_detect": true
});

Answer 1

Is this what you want ?

 particlesJS("particles-js", { "particles": { "number": { "value": 50, "density": { "enable": true, "value_area": 800 } }, "color": { "value": "#ffffff" }, "shape": { "type": "circle", "stroke": { "width": 0, "color": "#000000" }, "polygon": { "nb_sides": 5 }, "image": { "src": "img/github.svg", "width": 100, "height": 100 } }, "opacity": { "value": 0.5, "random": false, "anim": { "enable": false, "speed": 1, "opacity_min": 0.1, "sync": false } }, "size": { "value": 3, "random": true, "anim": { "enable": false, "speed": 40, "size_min": 0.1, "sync": false } }, "line_linked": { "enable": true, "distance": 150, "color": "#ffffff", "opacity": 0.4, "width": 1 }, "move": { "enable": true, "speed": 3, "direction": "none", "random": false, "straight": false, "out_mode": "out", "bounce": false, "attract": { "enable": false, "rotateX": 600, "rotateY": 1200 } } }, "interactivity": { "detect_on": "canvas", "events": { "onhover": { "enable": false, "mode": "repulse" }, "onclick": { "enable": false, "mode": "push" }, "resize": true }, "modes": { "grab": { "distance": 527.4388051113614, "line_linked": { "opacity": 1 } }, "bubble": { "distance": 599.3622785356379, "size": 63.93197637713472, "duration": 5.354303021585032, "opacity": 0.30367688779138985, "speed": 3 }, "repulse": { "distance": 271.7108996028225, "duration": 0.4 }, "push": { "particles_nb": 4 }, "remove": { "particles_nb": 2 } } }, "retina_detect": true }); 

 body { margin:0; } #particles-js { position:relative; width: 100%; height: 100vh; background-color: #222; background-repeat: no-repeat; background-size: cover; background-position: 50% 50%; } canvas { position: absolute; width: 100%; height: 100%; } .content { background:#000; height: 100vh; color: #fff; } .content h1 { margin-top:0; } 

 <div id="particles-js"> </div> <div class="content"> <h1>Content</h1> </div> <script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/jquery/2.1.3/jquery.min.js"></script> <script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/particles.js/2.0.0/particles.min.js"></script> 

Answer 2

Am Not good with js, but as for css, positioning two objects would be wrong simply because both of them can't take the entire space. I recommend u use absolute with relative of both relative, than position them using: left, right , top , bottom