body{background:#f5f5f5;margin:0;font-family:Arial,sans-serif}.container{background:#fff;border-radius:12px;max-width:500px;margin:50px auto;padding:20px;box-shadow:0 2px 10px #0000001a}h1{margin-bottom:5px}.subtitle{color:gray;margin-bottom:20px}.form{gap:10px;display:flex}.form input{flex:1;padding:10px}.form button{cursor:pointer;padding:10px 15px}.list{margin-top:20px}.task{cursor:pointer;border-bottom:1px solid #eee;justify-content:space-between;padding:10px;display:flex}.task span{flex:1}.done{color:gray;text-decoration:line-through}.empty{text-align:center;color:gray}