*{box-sizing:border-box;margin:0;padding:0;font-family:Arial,sans-serif}body{background:linear-gradient(90deg,#4facfe,#00f2fe);margin:0}.app-container{text-align:center;background:#fff;border-radius:12px;width:400px;margin:60px auto;padding:20px;box-shadow:0 8px 20px #0003}h1{margin-bottom:20px}.todo-form{gap:10px;margin-bottom:20px;display:flex}.todo-form input{border:1px solid #ccc;border-radius:8px;flex:1;padding:10px}.todo-form button{color:#fff;cursor:pointer;background:#4facfe;border:none;border-radius:8px;padding:10px 15px}.todo-form button:hover{background:#3a8de0}.todo-list{flex-direction:column;gap:10px;display:flex}.todo-item{background:#f5f5f5;border-radius:8px;justify-content:space-between;align-items:center;padding:10px;display:flex}.todo-item span{cursor:pointer}.todo-item.completed span{color:gray;text-decoration:line-through}.actions{gap:5px;display:flex}.actions button{cursor:pointer;border:none;border-radius:6px;padding:5px 10px}.actions button:hover{opacity:.8}.delete{color:#fff;background:#ff4d4d}