*{box-sizing:border-box;margin:0;padding:0}body{background:linear-gradient(135deg,#667eea 0%,#764ba2 100%);justify-content:center;align-items:center;min-height:100vh;padding:2rem;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,sans-serif;display:flex}.container{background:#fff;border-radius:10px;width:100%;max-width:600px;padding:2rem;box-shadow:0 10px 40px #0000001a}h1{color:#333;margin-bottom:.5rem;font-size:2rem}.subtitle{color:#666;margin-bottom:2rem}.add-todo-form{gap:.75rem;margin-bottom:2rem;display:flex}input[type=text]{border:2px solid #e0e0e0;border-radius:5px;flex:1;padding:.75rem;font-size:1rem}input[type=text]:focus{border-color:#667eea;outline:none}button{color:#fff;cursor:pointer;background:#667eea;border:none;border-radius:5px;padding:.75rem 1.5rem;font-size:1rem;transition:background .2s}button:hover:not(:disabled){background:#5568d3}button:disabled{cursor:not-allowed;background:#ccc}.todos-list{flex-direction:column;gap:.75rem;display:flex}.empty-state{text-align:center;color:#999;padding:3rem 1rem;font-size:1.1rem}.todo-item{background:#f9f9f9;border-radius:5px;align-items:center;gap:1rem;padding:1rem;transition:background .2s;display:flex}.todo-item:hover{background:#f0f0f0}.todo-item.completed .todo-title{color:#999;text-decoration:line-through}.todo-title{color:#333;flex:1;font-size:1rem}input[type=checkbox]{cursor:pointer;width:20px;height:20px}.delete-btn{background:#f44336;padding:.5rem 1rem;font-size:.875rem}.delete-btn:hover:not(:disabled){background:#d32f2f}.stats{text-align:center;color:#666;border-top:1px solid #e0e0e0;margin-top:1.5rem;padding-top:1.5rem}@media (width<=600px){.add-todo-form{flex-direction:column}button{width:100%}}