Help applying multiply blend mode to javascript

Hi,

I’m trying to figure out how to apply a blend mode of multiply to the javascript code below. I’m a complete novice with javascript, so it might be a simple solution, but I’m stumped. I’ve tried pasting this (“blendMode”: “multiply”,) in various places, but the circles always show up full opacity. Would greatly appreciate input!

<script src="https://cdn.jsdelivr.net/particles.js/2.0.0/particles.min.js"></script> 
<script type="text/javascript">
particlesJS("particles-js",
{
  "particles": {
    "number": {
      "value": 10,
      "density": {
        "enable": false,
        "value_area": 2250
      }
    },
    "color": {
      "value": ["#262993","#B42C2A","#BC818E","#D9B94E","#4D7E76"] 
    },
    "shape": {
      "type": "circle",
      "stroke": {
        "width": 0,
        "color": "#000000"
      },
      "polygon": {
        "nb_sides": 5
      },
      "image": {
        "src": "img/github.svg",
        "width": 100,
        "height": 100
      }
    },
    "opacity": {
      "value": 1,
      "random": false,
      "anim": {
        "enable": false,
        "speed": 1,
        "opacity_min": 0.1,
        "sync": false
      }
    },
    "size": {
      "value": 255,
      "random": false,
      "anim": {
        "enable": false,
        "speed": 45,
        "size_min": 0.1,
        "sync": false
      }
    },
    "line_linked": {
      "enable": false,
      "distance": 150,
      "color": "#ffffff",
      "opacity": 0.4,
      "width": 1
    },
    "move": {
      "enable": true,
      "speed": 10,
      "direction": "none",
      "random": true,
      "straight": false,
      "out_mode": "out",
      "bounce": false,
      "attract": {
        "enable": true,
        "rotateX": 10000,
        "rotateY": 10000
      }
    }
  },
  "interactivity": {
    "detect_on": "window",
    "events": {
      "onhover": {
        "enable": true,
        "mode": "bubble"
      },
      "onclick": {
        "enable": false,
        "mode": "repulse"
      },
      "resize": true
    },
    "modes": {
      "grab": {
        "distance": 400,
        "line_linked": {
          "opacity": 1
        }
      },
      "bubble": {
        "distance": 415,
        "size": 200,
        "duration": 6,
        "opacity": 0.65,
        "speed": 1
      },
      "repulse": {
        "distance": 382,
        "duration": 0.4
      },
      "push": {
        "particles_nb": 4
      },
      "remove": {
        "particles_nb": 2
      }
    }
  },
  "retina_detect": true
}
  );var count_particles, stats, update; stats = new Stats; stats.setMode(0); stats.domElement.style.position = 'absolute'; stats.domElement.style.left = '0px'; stats.domElement.style.top = '0px'; document.body.appendChild(stats.domElement); count_particles = document.querySelector('.js-count-particles'); update = function() { stats.begin(); stats.end(); if (window.pJSDom[0].pJS.particles && window.pJSDom[0].pJS.particles.array) { count_particles.innerText = window.pJSDom[0].pJS.particles.array.length; } requestAnimationFrame(update); }; requestAnimationFrame(update);;
</script>