Generating Randomness

*{box-sizing:border-box}body{background:#111522;color:#f5f2eb;font-family:system-ui,sans-serif;margin:0}button{font:inherit}.study{margin:0 auto;max-width:1100px;min-height:100vh;padding:clamp(20px,4vw,42px)}.study-label{color:#95efd2;font-size:12px;letter-spacing:.08em;margin:0 0 24px}header h2{font-size:clamp(24px,4vw,40px);letter-spacing:-.04em;margin:0 0 12px}header p{color:#aeb7c9;line-height:1.6;margin:0 0 24px;max-width:62ch}.controls{display:flex;flex-wrap:wrap;gap:8px;margin:20px 0}button{background:#26314b;border:1px solid #617394;border-radius:9px;color:#f5f2eb;cursor:pointer;padding:9px 14px}button:hover{background:#334261}button:focus-visible{outline:3px solid #95efd2;outline-offset:3px}button:disabled{cursor:default;opacity:.45}.stage{align-items:center;background:radial-gradient(ellipse at top,#243253,#141c2d);border:1px solid #3d4c68;border-radius:20px;display:flex;justify-content:center;min-height:220px;overflow:hidden;position:relative}.note{color:#aeb7c9;font-size:13px;line-height:1.5}.readout{color:#95efd2;font-family:ui-monospace,monospace;font-size:13px;min-height:2em}.stage svg{display:block;max-width:100%}code{font-family:ui-monospace,monospace}button[aria-pressed="true"]{background:#95efd2;color:#111522}

.values{display:flex;flex-wrap:wrap;gap:12px;margin:20px 0}.values div{background:#202b42;border-radius:12px;color:#aeb7c9;flex:1;min-width:110px;padding:16px}.values strong{color:#f5f2eb;display:block;font-family:ui-monospace,monospace;font-size:20px;margin-top:8px}.random-world{height:120px;left:50%;position:absolute;top:50%;transform:translate(-50%,-50%);transform-origin:center;width:940px}.axis{border-top:1px dashed #798bad;left:20px;position:absolute;right:20px;top:60px}.box{background:#95efd2;border-radius:18px;height:72px;left:434px;position:absolute;top:24px;width:72px}

gsap.registerPlugin();

/// random number between -100 and 100
let randomNum = gsap.utils.random(-100, 100);
console.log("random number between -100 and 100", randomNum)

// snapped to closest increment of 5
let randomSnap = gsap.utils.random(-100, 100, 5);
console.log("snapped to closest increment of 5", randomSnap)

// get a random value from an array of colors 
let randomValue = gsap.utils.random(["red", "blue", "green"]); 
console.log("a random value from an array of colors", randomValue)

let colors = ["#0ae448", "#fec5fb", "#ff8709","#9d95ff", "#abff84", "#00bae2"]

// use the shortcut string syntax or call the util methods in a tween
gsap.to('.box', {
  x: "random(-400, 400, 5)",
  backgroundColor: () => gsap.utils.random(colors),
  repeat: -1,
  repeatRefresh: true,
  duration: 1,
  repeatDelay: 0.2
})
document.getElementById('random-number').textContent=randomNum.toFixed(2);document.getElementById('random-snap').textContent=randomSnap;document.getElementById('random-color').textContent=randomValue;
const stage=document.getElementById('random-stage');const world=document.querySelector('.random-world');
new ResizeObserver(()=>world.style.transform='translate(-50%,-50%) scale('+Math.min(1,stage.clientWidth/940)+')').observe(stage);
let paused=false;document.getElementById('toggle').addEventListener('click',e=>{paused=!paused;gsap.getTweensOf('.box').forEach(t=>t.paused(paused));e.currentTarget.textContent=paused?'재생':'정지'});

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