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HTML

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Adding Classes

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About the <head>

In CodePen, whatever you write in the HTML editor is what goes within the <body> tags in a basic HTML5 template. If you need things in the <head> of the document, put that code here.

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Insecure Resource

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CSS

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CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

About CSS Base

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                <svg viewBox="0 0 1200 870" preserveAspectRatio="xMinYMin meet" style="enable-background:new 0 0 1200 870;">  
  <defs>
    <path id="shape" d="M 331 162 C 359.8 129.7 399.1 107.2 441.3 97.6 C 483.5 88.1 528.4 91.5 569 106.5 C 609.6 121.4 645.8 147.8 673.1 181.4 C 700.5 214.9 719 255.4 727.4 297.8 C 744.2 382.7 719.1 473.6 666.4 542.2 C 613.7 610.8 535.1 657.6 451 678 C 408.1 688.4 363.4 692.3 319.6 687.1 C 275.7 681.9 232.7 667.4 196 643 C 159.2 618.6 128.8 584.1 111.3 543.5 C 93.8 503 89.7 456.4 102 414 C 110.9 383.3 128.2 355.1 151.5 333.2 C 174.7 311.3 203.8 295.6 234.8 288.1 C 265.9 280.7 298.9 281.3 329.6 289.9 C 360.4 298.4 389 314.8 412 337 C 449.9 373.5 472.2 426.5 468.6 479 C 466.8 505.3 458.7 531.1 444.8 553.5 C 430.9 575.8 411.2 594.6 388 607 C 355.9 624.2 317.5 628.9 282 621 C 254.9 615 229.2 601.7 209.7 581.9 C 190.2 562.1 177.2 535.7 175 508 C 173.5 488.9 177 469.6 184.7 452.1 C 192.3 434.6 204.1 418.9 218.4 406.3 C 247.2 381.1 285.8 368.5 324 368 C 365.7 367.4 406.7 380.5 443.5 400.1 C 480.3 419.7 513.3 445.7 545.2 472.6 C 577.1 499.4 608.2 527.4 642.2 551.5 C 676.2 575.6 713.5 596 754 606 C 801.2 617.6 851.9 614.4 897.6 597.6 C 943.2 580.8 983.7 550.5 1013.2 511.8 C 1042.8 473.2 1061.4 426.3 1067 378 C 1072.7 329.7 1065.5 280 1047 235 C 1026.5 185.1 992 140.9 947.8 110 C 903.7 79 849.9 61.6 796 62 C 753.9 62.3 711.8 73.5 675.8 95.1 C 639.7 116.7 609.8 148.9 592 187 C 572.6 228.5 567.9 276.6 577.8 321.4 C 587.6 366.1 611.7 407.5 645 439 C 674.9 467.2 711.4 487.4 748.3 505.3 C 785.3 523.3 823.3 539.4 858.3 561 C 893.2 582.7 925.4 610.4 945.4 646.4 C 955.3 664.4 962.1 684.2 964.1 704.7 C 966.1 725.1 963.2 746.2 955 765 C 947.2 782.8 934.7 798.4 919.6 810.6 C 904.5 822.8 886.9 831.8 868.4 837.8 C 831.5 849.7 791.7 849.8 753 846 C 648.1 835.7 545.9 796.8 462 733 C 398.4 684.6 345.4 621.9 310.9 549.9 C 276.5 477.8 260.8 396.5 269 317 C 274.8 260.7 293.3 204.2 331 162" />
  </defs>    
</svg>
!

CSS 

              
                body {
  overflow: hidden;
}

svg {
  position: absolute;
  top: 0;
  left: 0;
  height: 100%;
  width: 100%;
}

polyline {
  fill: none;  
  visibility: hidden;
  stroke-width: 0; 
  stroke-linecap: round;
  stroke-linejoin: round;
}
!

JS 

              
                TweenLite.defaultEase = Linear.easeNone;

var colors = ["#EA4335", "#FBBC05", "#34A853", "#4285F4"];

var svgns = "http://www.w3.org/2000/svg";
var root  = document.querySelector("svg");

var time  = 6;
var lines = 100;
var step  = 1 / colors.length;
var timeStep = time * step;
var timeFill = time - timeStep;

var cursor = { x: 0, y: 0 };
var values = MorphSVGPlugin.pathDataToBezier("#shape");
var bezier = TweenLite.to(cursor, time, { 
  bezier: { values, type: "cubic" }, 
  puased: true 
}).progress(1).progress(0);

var startX = cursor.x;
var startY = cursor.y;

var tl = colors.reduce(bezierPath, new TimelineMax({ repeat: -1, repeatDelay: 0.5 }));

function bezierPath(timeline, stroke, index) {
    
  var dash = { head: 0, tail: 0 };
  var path = document.createElementNS(svgns, "polyline");
  
  path.style.stroke = stroke;
  root.appendChild(path);   
  
  var tl = new TimelineMax({ onUpdate, onUpdateParams: [path, dash] })
    .set(path, { autoAlpha: 1, strokeWidth: 30 })  
    .to(dash, timeStep, { head: step })
    .to(dash, timeStep, { head: step * 2, tail: step })
    .to(dash, timeFill, { head: 1, tail: 1 - step })
    .to(dash, timeStep, { tail: 1 })
    .set(path, { autoAlpha: 0, strokeWdith: 0 });
    
  return timeline.add(tl, timeStep * index);
}

function onUpdate(path, dash) {
  
  var points = [];
    
  var i = lines + 1;
  var start = dash.head;
  var delta = dash.tail - start;
  
  while (i--) {
    
    // var progress = lerp(dash.head, dash.tail, i / lines);    
    var progress = start + delta * i / lines;
    bezier.progress(progress);
    points.push(cursor.x, cursor.y);
  }
    
  path.setAttribute("points", points);
}

function lerp(min, max, amt) {
  return min + (max - min) * amt;
}
!
999px

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