const canvas = document.getElementById('bgCanvas');
const ctx = canvas.getContext('2d');

function resize() {
    canvas.width = window.innerWidth;
    canvas.height = window.innerHeight;
}

window.addEventListener('resize', resize);
resize();

const particles = [];

for (let i = 0; i < 80; i++) {
    particles.push({
        x: Math.random() * canvas.width,
        y: Math.random() * canvas.height,
        vx: (Math.random() - 0.5) * 0.5,
        vy: (Math.random() - 0.5) * 0.5,
        size: Math.random() * 2 + 1
    });
}

function animate() {
    ctx.clearRect(0, 0, canvas.width, canvas.height);

    particles.forEach(p => {
        p.x += p.vx;
        p.y += p.vy;

        if (p.x < 0 || p.x > canvas.width) p.vx *= -1;
        if (p.y < 0 || p.y > canvas.height) p.vy *= -1;

        ctx.beginPath();
        ctx.arc(p.x, p.y, p.size, 0, Math.PI * 2);
        ctx.fillStyle = 'rgba(34,197,94,0.8)';
        ctx.shadowBlur = 10;
        ctx.shadowColor = 'rgba(34,197,94,0.8)';
        ctx.fill();
        ctx.shadowBlur = 0;
    });

    requestAnimationFrame(animate);
}

animate();