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!
Insecure Resource

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CSS

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CSS Base

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JavaScript

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JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

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Babel includes JSX processing.

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HTML 

              
                <p>
  Logo for the 404 page of <a href="https://www.strangeplanet.fr/">my website</a>
</p>

<div id="notfound"></div>

<p class="small">
  <b>Inspirations:</b><br>
  <a href="https://codepen.io/mistic100/pen/GFHkm">Colorful Tiles</a> by mistic100<br>
  <a href="https://codepen.io/jorgeatgu/pen/zmAnr">SVG error 404</a> by jorgeatgu<br>
  <a href="https://codepen.io/kaypooma/pen/ehfjC">Glitchy 404 Page</a> by kaypooma<br>
</p>
!

CSS 

              
                @font-face {
  font-family:'Ubuntu';
  font-style:normal;
  font-weight:700;
  src:local('Ubuntu Bold'), local('Ubuntu-Bold'), url('http://themes.googleusercontent.com/static/fonts/ubuntu/v4/0ihfXUL2emPh0ROJezvraD8E0i7KZn-EPnyo3HZu7kw.woff') format('woff');
}

html, body {
  padding:0; margin:0;
  height:100%; width:100%;
}
body {
  font-family:"Calibri",sans-serif;
  background:radial-gradient(#fff, #ccc);
  background:radial-gradient(#ffffff, #fdfdfd 16%, #fbfbfb 33%, #f8f8f8 49%, #efefef 66%, #dfdfdf 82%, #bfbfbf 100%);  
}

#notfound {
  margin:0 auto;
}
#notfound svg {
  -webkit-animation: noise 2s linear infinite;
  animation: noise 2s linear infinite;
}
@-webkit-keyframes noise {
  0%, 3%, 5%, 42%, 44%, 100% { -webkit-transform: scaleY(1); }  
  4.3% { -webkit-transform: scaleY(1.7); }
  43% { -webkit-transform: scaleX(1.5); }
}
@keyframes noise {
  0%, 3%, 5%, 42%, 44%, 100% { transform: scaleY(1); }  
  4.3% { transform: scaleY(1.7); }
  43% { transform: scaleX(1.5); }
}

p {
  text-align:center;
}
p.small {
  font-size:0.8em;
  opacity:0.5;
}
!

JS 

              
                if (!SVG.supported) {
    alert('SVG not supported !');
}
else {
    // parameters
    var a = 40,
        speed = 50,
        points = [
            [ , ,1,1, , ,1,1, , ,1,1,1,1,1,1, , ,1,1, , ,1,1],
            [ ,1,1, , ,1,1, , ,1,1, , ,1,1, , ,1,1, , ,1,1, ],
            [1,1,1,1,1,1, , ,1,1, , ,1,1, , ,1,1,1,1,1,1, , ],
            [ , , ,1,1, , ,1,1, , ,1,1, , , , , , ,1,1, , , ],
            [ , ,1,1, , ,1,1,1,1,1,1, , , , , , ,1,1, , , , ]
        ],
        colors = [
            '#ED1156', '#ED194E', '#ED2247', '#ED2B3F', '#EE3438',
            '#EE3D31', '#EE4529', '#EF4E22', '#EF571A', '#EF6013',
            '#F0690C', '#E8720E', '#E17B10', '#D98512', '#D28E14',
            '#CB9816', '#C3A118', '#BCAA1A', '#B4B41C', '#ADBD1E',
            '#A6C721', '#96C62F', '#87C53E', '#78C44D', '#69C35C',
            '#5AC26B', '#4AC17A', '#3BC089', '#2CBF98', '#1DBEA7',
            '#0EBDB6', '#0EBAB0', '#0EB8AA', '#0EB5A4', '#0EB39E',
            '#0EB098', '#0EAE92', '#0EAB8C', '#0EA986', '#0EA680',
            '#0EA47B', '#269376', '#3F8372', '#58736E', '#71626A',
            '#895266', '#A24262', '#BB315E', '#D4215A'
        ],
        shadowColors = ['#0055ff', '#ff0000'],
        textColors = ['#012C33', '#12575E'];
    
    // computed parameters
    var a2 = a/2,
        h = Math.round(a2*Math.sqrt(3) *100)/100,
        grid = [points[0].length, points.length],
        size = [(grid[0]/2+0.5)*a+a*2, grid[1]*h+a*3],
        nb_colors = colors.length,
        objects = [],
        groups = [];

    
    // init canvas
    var container = document.getElementById('notfound');
    container.style.width = size[0]+'px';
    container.style.height = size[1]+'px';
  
    var simplex = new SimplexNoise(),
        paper = SVG(container).size(size[0], size[1]).viewbox(0, 0, size[0], size[1]);
        up = paper.defs().path('M'+ a2 +',0 l'+ a2 +','+ h +' l-'+ a +',0 l'+ a2 +',-'+ h),
        down = paper.defs().path('M0,0 l'+ a +',0 l-'+ a2 +','+ h +' -'+ a2 +',-'+ h),
        shadow = [paper.group(), paper.group()];

    // draw objects
    for (var l=0; l<grid[1]; l++) {
        objects[l] = [];
        groups[l] = paper.group();
        
        for (var c=0; c<grid[0]; c++) {
            if (!points[l][c]) {
                continue;
            }
            
            var rnd = Math.round((simplex.noise(c/10, l/10)+1) / 2 * nb_colors),
                cid = rnd - Math.floor(rnd/nb_colors)*nb_colors,
                pos = [c*a2+a, l*h+a],
                use;
            
            if ((l%2==0 && c%2==0) || (l%2==1 && c%2==1)) {
                use = up;
            }
            else {
                use = down;
            }
            
            var el = paper.use(use)
              .move(pos[0], pos[1])
              .style('fill:'+colors[cid])
              .data('i', rnd);

            groups[l].add(el);
            objects[l][c] = el;
            
            shadow[0].use(use).move(pos[0], pos[1]);
            shadow[1].use(use).move(pos[0], pos[1]);
        }
    }
    
    
    // draw text
    var text = paper.text('Page not found!')
      .font({
          family: 'Ubuntu, Calibri',
          size: a
      })
      .opacity(0.7)
      .cx(size[0]/2-a2)
      .y(size[1]-a-a2);
        
    shadow[0].add(text.clone());
    shadow[1].add(text.clone());
    
    text.fill(
        paper.gradient('linear', function(stop) {
            stop.at(0, textColors[0]);
            stop.at(1, textColors[1]);
        }).from(0,0).to(0,1)
    );
    
    
    // animate shadows
    shadow[0].back()
      .fill(shadowColors[0])
      .animate(speed*4).loop()
      .during(function(i) {
          if (i<0.1)
              this.move(-a/4, 0);
          else if (i>=0.8)
              this.move(a/12, 0);

          if (i<0.1)
              this.opacity(0.1);
          else if (i>=0.4 && i<0.5)
              this.opacity(0.5);
          else if (i>=0.7 && i<0.8)
              this.opacity(0.3)
          else if (i>=0.9)
              this.opacity(0.6);
          else
              this.opacity(0);
      });
    
    shadow[1].back()
      .fill(shadowColors[1])
      .animate(speed*6).loop()
      .during(function(i) {
          if (i<0.1)
              this.move(a/4, 0);
          else if (i>=0.8)
              this.move(-a/12, 0);
              
          if (i<0.1)
              this.opacity(0.1);
          else if (i>=0.4 && i<0.5)
              this.opacity(0.5);
          else if (i>=0.7 && i<0.8)
              this.opacity(0.3)
          else if (i>=0.9)
              this.opacity(0.6);
          else
              this.opacity(0);
      });
    
    
    var counter = 0;
    setInterval(function() {
        // animate position
        for (var l=0, i=groups.length; l<i; l++) {
            if (Math.random()<0.5) {
                groups[l].x(Math.round(Math.random()*a/5));
            }
        }
        
        // animate colors        
        for (var l=0, i=objects.length; l<i; l++) {
            for (var c=0, j=objects[l].length; c<j; c++) {
                if (!objects[l][c]) {
                    continue;
                }
                
                var cid = objects[l][c].data('i') + counter;
                cid-= Math.floor(cid/nb_colors)*nb_colors;
                
                objects[l][c].style('fill:'+colors[cid]);
            }
        }
        
        counter++;
        if (counter == nb_colors) {
            counter = 0;
        }
    }, speed);
}
!
999px

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