.xxxbody{font-family:sans-serif;display:flex;justify-content:center;align-items:center;height:100vh;margin:0;background-color:#f5f5f5}.timer-container{text-align:center;background:#fff;padding:0;border-radius:8px;margin-bottom:1em}.display{font-size:3.5rem;font-weight:700;font-family:monospace;margin-bottom:0;color:#333}.controls button{font-size:1rem;margin:0 .25rem;border:none;border-radius:4px;cursor:pointer;transition:background .2s}#startBtn{background-color:#4caf50;color:#fff}#pauseBtn{background-color:#ff9800;color:#fff}#stopBtn{background-color:#f44336;color:#fff}button:disabled{background-color:#ccc!important;cursor:not-allowed}.input-group{margin-top:1.5rem}.input-group input{font-size:1rem;padding:.5rem;width:100px;text-align:center}