HTML5動畫愛心代碼是一種表達愛和浪漫的方式，它可以通過在Web頁面中添加代碼實現動畫效果，讓用戶感受到浪漫和夢想。

<canvas id="canvas" width="400" height="400" style="background-color: #eee;"></canvas>
<script>
var canvas = document.getElementById("canvas");
var context = canvas.getContext("2d");
var width = canvas.width;
var height = canvas.height;
var size = width / 2;
var step = 2;
var angle = 10;
var color = "#ff0000";
var time = 0;
var offsetX = 0;
var offsetY = 0;
function drawHeart() {
context.beginPath();
for (var i = angle; i< angle + 360; i += step) {
var x = size * (16 * Math.pow(Math.sin(i), 3));
var y = size * (13 * Math.cos(i) - 5 * Math.cos(2 * i) - 2 * Math.cos(3 * i) - Math.cos(4 * i));
context.lineTo(x + offsetX, y + offsetY);
}
context.strokeStyle = color;
context.lineWidth = 2;
context.stroke();
}
function stepHeart() {
time++;
if (time % 50 === 0) {
angle += 10;
if (angle >= 360) {
angle = 10;
}
color = "#" + (Math.random() * 0xFFFFFF<< 0).toString(16);
}
if (time % 200 === 0) {
offsetX = Math.random() * 40 - 20;
offsetY = Math.random() * 40 - 20;
}
drawHeart();
}
setInterval(stepHeart, 1000 / 30);
</script>

以上是一個簡單的HTML5動畫愛心代碼，通過JavaScript設置canvas畫布的寬高、生成一個矢量圖愛心的軌跡，并且實現了動態改變軌跡顏色和位置的效果。這種方式能夠完美地重現濃濃的愛意，祝福各位情侶和愛情永遠甜蜜！