javascript+css创建的随机向上浮动的气球动画特效

使用方法

const balloonContainer = document.getElementById("balloon-container");

function random(num) {
  return Math.floor(Math.random() * num);
}

function getRandomStyles() {
  var r = random(255);
  var g = random(255);
  var b = random(255);
  var mt = random(200);
  var ml = random(50);
  var dur = random(5) + 5;
  return `
  background-color: rgba(${r},${g},${b},0.7);
  color: rgba(${r},${g},${b},0.7); 
  box-shadow: inset -7px -3px 10px rgba(${r - 10},${g - 10},${b - 10},0.7);
  margin: ${mt}px 0 0 ${ml}px;
  animation: float ${dur}s ease-in infinite
  `;
}

function createBalloons(num) {
  for (var i = num; i > 0; i--) {
    var balloon = document.createElement("div");
    balloon.className = "balloon";
    balloon.style.cssText = getRandomStyles();
    balloonContainer.append(balloon);
  }
}

function removeBalloons() {
  balloonContainer.style.opacity = 0;
  setTimeout(() => {
    balloonContainer.remove()
  }, 500)
}

window.addEventListener("load", () => {
  createBalloons(30)
});

window.addEventListener("click", () => {
  removeBalloons();
});