body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', sans-serif;
    margin: 0;
    padding: 20px;
    background-color: #f5f5f5;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    user-select: none;
    -webkit-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
}

.game-container {
    background: white;
    padding: 30px;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.time-left {
    font-size: 16px;
    font-weight: 500;
}

.game-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
}

.shuffle-button {
    padding: 8px 12px;
    font-size: 14px;
    border-radius: 6px;
    border: none;
    cursor: pointer;
    font-weight: 500;
    transition: all 0.2s ease;
}

.shuffle-button:enabled {
    background: #4CAF50;
    color: white;
}

.shuffle-button:enabled:hover {
    background: #45a049;
    transform: translateY(-1px);
}

.shuffle-button:disabled {
    background: #e0e0e0;
    color: #666;
    cursor: not-allowed;
}

.board {
    display: flex;
    flex-direction: column;
    gap: 2px;
    cursor: default;
}

.row {
    display: grid;
    grid-template-columns: repeat(10, 1fr);
    gap: 2px;
    justify-content: center;
}

.cell {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 4px;
    font-size: 16px;
    font-weight: 500;
    text-align: center;
    background-color: rgb(240, 240, 240);
    color: black;
    user-select: none;
    -webkit-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    cursor: pointer;
    transition: background-color 0.1s ease;
    position: relative;
    box-sizing: border-box;
    border: 2px solid transparent;
}

.cell.selected {
    background-color: rgb(100, 180, 255);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    border: 2px solid #1976d2;
    z-index: 1;
}

.cell.selected.dragging {
    background-color: rgb(30, 144, 255);
    border: 2px solid #0d47a1;
    box-shadow: 0 0 8px 2px rgba(30,144,255,0.3);
}

.cell.removed {
    background-color: rgb(236, 111, 111);
    cursor: not-allowed;
}

.cell:hover:not(.removed) {
    background-color: rgb(220, 220, 220);
}

.cell:active:not(.removed) {
    background-color: rgb(200, 200, 200);
}