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<!DOCTYPE html> <html> <head> <link rel="stylesheet" href="style.css"> </head> <body> <h1>Dùng phím mũi tên để di chuyển!</h1> <div class="box"> <div id="robot">O</div> </div> <script src="script.js"></script> </body> </html>
.box { width: 400px; height: 400px; background-color:#4287f5; position: relative; margin:150px; border:solid 4px white; } body { background-color:#275db3; text-align:center; height:100px; } #robot { font-size:50px; position: absolute; top: 0; left: 0; transition: 0.1s; }
let x = 0; let y = 0; const robot = document.getElementById('robot'); document.addEventListener('keydown', function() { if (event.key === "ArrowRight") { x = x + 20; } else if (event.key === "ArrowLeft") { x = x - 20; } else if (event.key === "ArrowDown") { y = y + 20; } else if (event.key ==="ArrowUp") { y = y - 20; } robot.style.left = x + "px"; robot.style.top = y + "px"; if (x<0 || x>360 || y<0 || y>360) { alert('You LOST, GAME OVER'); x = 0; y = 0; robot.style.left = "0px"; robot.style.right = "0px"; } });