script.js

var root = {
  wavecolor: {
    r: 45, g: 26, b: 196
  },
  rainbowSpeed: 0.5,
  rainbow: false,
  matrixspeed: 33
};

var c = document.getElementById("c");
var ctx = c.getContext("2d");

var hueFw = false;
var hue = -0.01;

// making the canvas full screen
c.height = window.innerHeight;
c.width = window.innerWidth;

// the characters
var matrix_str = "Mohak Bajaj MOHAK BAJAJ mohak bajaj abcdefghijklmnopqrstuvwxyz ABCDEFGHIJKLMNOPQRSTUVWXYZ ੧੨੩੪੫੬੭੮੯੦ੳਅਰਤਯਪਸਦਗਹਜਕਲਙੜਚਵਬਨਮੲਥਫਸ਼ਧਘਝਖਲ਼ੜ੍ਹਛਭਣ \
                  12345567890!@#$%^&*()_+{}|:\"<>? १२३४५६७८९अरतयपसदगहजकलङषचवबनमआथय़फशधघझखळक्षछभणऒ ❤️";

// converting the string into an array of single characters
var characters = matrix_str.split("");
var font_size = 14;
var columns = c.width / font_size;    // number of columns for the rain
var gradient = ctx.createLinearGradient(0, 10, 0, 200);
// an array of drops - one per column
var drops = [];
// x below is the x coordinate
// 1 = y-coordinate of the drop (same for every drop initially)
for (var x = 0; x < columns; x++)
  drops[x] = 1;

// drawing the characters
function draw() {
  // Get the BG color based on the current time i.e. rgb(hh, mm, ss)
  // translucent BG to show trail

  ctx.fillStyle = "rgba(0,0,0, 0.05)";
  ctx.fillRect(0, 0, c.width, c.height);

  ctx.fillStyle = "#BBB"; // grey text
  ctx.font = font_size + "px arial";

  // looping over drops
  for (var i = 0; i < drops.length; i++) {
    // background color
    ctx.fillStyle = "rgba(10,10,10, 1)";
    ctx.fillRect(i * font_size, drops[i] * font_size, font_size, font_size);
    // a random character to print
    var text = characters[Math.floor(Math.random() * characters.length)];
    // x = i * font_size, y = value of drops[i] * font_size

    if (root.rainbow) {
      hue += (hueFw) ? 0.01 : -0.01;
      var rr = Math.floor(127 * Math.sin(root.rainbowSpeed * hue + 0) + 128);
      var rg = Math.floor(127 * Math.sin(root.rainbowSpeed * hue + 2) + 128);
      var rb = Math.floor(127 * Math.sin(root.rainbowSpeed * hue + 4) + 128);
      ctx.fillStyle = 'rgba(' + rr + ',' + rg + ',' + rb + ')';
    } else {
      ctx.fillStyle = 'rgba(' + root.wavecolor.r + ',' + root.wavecolor.g + ',' + root.wavecolor.b + ')';
    }

    ctx.fillText(text, i * font_size, drops[i] * font_size);
    // Incrementing Y coordinate
    drops[i]++;
    // sending the drop back to the top randomly after it has crossed the screen
    // adding randomness to the reset to make the drops scattered on the Y axis
    if (drops[i] * font_size > c.height && Math.random() > 0.975)
      drops[i] = 0;
  }
}

window.onresize = () => {
  location.reload();
}

var interval = setInterval(draw, root.matrixspeed);

function hexToRgb(hex) {
  var result = /^#?([a-f\d]{2})([a-f\d]{2})([a-f\d]{2})$/i.exec(hex);
  return result ? {
    r: parseInt(result[1], 16),
    g: parseInt(result[2], 16),
    b: parseInt(result[3], 16)
  } : null;
}