RAINBOW Illusion - Only 3 Colors.html

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>RAINBOW Illusion — Only 3 Colors</title>
<style>
  html, body {
    margin: 0;
    height: 75%;
    background: #000;
    overflow: hidden;
  }
  body {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    font-family: "Futura Bold", system-ui, sans-serif;
  }
  #container {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 80vh;
    width: 100vw;
  }
  #word {
    font-size: 250px;
    font-weight: 900;
    color: #ffffff;
    display: inline-flex;
  }
  #word span {
    display: inline-block;
  }
  #A + span,
  #I,
  #N,
  #B,
  #O,
  #W {
    margin-left: -8px;
  }
  #controls {
    position: fixed;
    bottom: 20px;
  }
  #toggle {
    padding: 8px 18px;
    font-size: 32px;
    font-weight: 600;
    cursor: pointer;
  }
</style>
</head>
<body>
<div id="container">
  <div id="word">
    <span id="R">R</span>
    <span id="A">A</span>
    <span id="I">I</span>
    <span id="N">N</span>
    <span id="B">B</span>
    <span id="O">O</span>
    <span id="W">W</span>
  </div>
</div>

<div id="controls">
  <button id="toggle">PAUSE</button>
</div>

<script>
  const R = "#ff0000";
  const G = "#00ff00";
  const B = "#0000ff";

  const ORANGE = [R, R, R, G, R, G];
  const YELLOW = [G, G, R, G, G, R];
  const INDIGO = [B, B, B, B, B, R];
  const PURPLE = [B, R, B, R, B, R];

  const elR = document.getElementById("R");
  const elA = document.getElementById("A");
  const elI = document.getElementById("I");
  const elN = document.getElementById("N");
  const elB = document.getElementById("B");
  const elO = document.getElementById("O");
  const elW = document.getElementById("W");

  elR.style.color = R;
  elN.style.color = G;
  elB.style.color = B;

  let frame = 0;
  let playing = true;

  const toggleBtn = document.getElementById("toggle");
  toggleBtn.addEventListener("click", () => {
    playing = !playing;
    toggleBtn.textContent = playing ? "PAUSE" : "PLAY";

    // restore defaults immediately when paused
    if (!playing) {
      elR.style.color = R;
      elN.style.color = G;
      elB.style.color = B;
      elW.style.color = PURPLE[frame % 6];

    }
  });

  function animate() {
    if (playing) {
      const f = frame % 6;

      elA.style.color = ORANGE[f];
      elI.style.color = YELLOW[f];
      elO.style.color = INDIGO[f];
      elW.style.color = PURPLE[f];

      const flicker = (frame % 15 === 0);
      elR.style.color = flicker ? "#000000" : R;
      elN.style.color = flicker ? "#000000" : G;
      elB.style.color = flicker ? "#000000" : B;
      elW.style.color = flicker ? "#000000" : W;

      frame++;
    }

    requestAnimationFrame(animate);
  }

  animate();
</script>
</body>
</html>