.level-selector {
    display: flex;
    gap: 10px;
    justify-content: center;
    flex-wrap: wrap;
    margin: 0 auto 20px;
    max-width: 720px;
    padding: 0 20px;
}

.level-btn {
    padding: 10px 22px;
    border-radius: 10px;
    border: 2px solid var(--light-quaternary);
    background: white;
    color: var(--gray-dark);
    font-size: 0.88rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    font-family: inherit;
}

.level-btn:hover { border-color: var(--primary); color: var(--primary); }
.level-btn.active { border-color: var(--primary); background: var(--primary); color: white; }

.ng-grid-wrap {
    display: inline-grid;
    grid-template-areas:
        "corner col-clues"
        "row-clues board";
    grid-template-columns: auto 1fr;
    grid-template-rows: auto 1fr;
    gap: 4px;
    user-select: none;
}

.ng-col-clues {
    grid-area: col-clues;
    display: flex;
    gap: 3px;
}

.ng-col-clue {
    width: 36px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: flex-end;
    gap: 1px;
    padding-bottom: 4px;
}

.ng-col-clue span {
    font-size: 0.72rem;
    font-weight: 700;
    color: var(--dark);
    line-height: 1.2;
    font-family: 'JetBrains Mono', monospace;
}

.ng-row-clues {
    grid-area: row-clues;
    display: flex;
    flex-direction: column;
    gap: 3px;
}

.ng-row-clue {
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: flex-end;
    gap: 4px;
    padding-right: 6px;
}

.ng-row-clue span {
    font-size: 0.72rem;
    font-weight: 700;
    color: var(--dark);
    font-family: 'JetBrains Mono', monospace;
}

.ng-board {
    grid-area: board;
    display: inline-grid;
    gap: 3px;
    background: var(--light-tertiary);
    border: 2px solid var(--light-quaternary);
    border-radius: 10px;
    padding: 6px;
}

.ng-cell {
    width: 36px;
    height: 36px;
    border-radius: 5px;
    background: white;
    border: 1.5px solid var(--light-quaternary);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.85rem;
    color: var(--gray-light);
    transition: background 0.1s ease, transform 0.1s ease;
}

.ng-cell:hover { background: var(--light-secondary); border-color: rgba(37,99,235,0.3); }

.ng-cell.filled {
    background: var(--dark);
    border-color: var(--dark-secondary);
    color: transparent;
    animation: cellFill 0.15s ease both;
}

.ng-cell.crossed {
    background: rgba(239, 68, 68, 0.07);
    border-color: rgba(239, 68, 68, 0.2);
    color: #ef4444;
}

.ng-cell.error {
    background: rgba(239, 68, 68, 0.15);
    border-color: #ef4444;
    animation: errorShake 0.3s ease;
}

.ng-cell.revealed-correct { background: var(--dark); border-color: var(--dark-secondary); }
.ng-cell.revealed-empty   { background: white; border-color: rgba(37,99,235,0.15); }

@keyframes cellFill {
    from { transform: scale(0.8); }
    to   { transform: scale(1); }
}

@keyframes errorShake {
    0%, 100% { transform: translateX(0); }
    25%  { transform: translateX(-3px); }
    75%  { transform: translateX(3px); }
}

/* 5-col band lines every 5 cells */
.ng-board.size-10 .ng-cell:nth-child(5n) { border-right: 2px solid rgba(37,99,235,0.2); }
.ng-board.size-10 .ng-cell:nth-child(n+46):nth-child(-n+50) { border-bottom: 2px solid rgba(37,99,235,0.2); }

@media (max-width: 540px) {
    .ng-cell { width: 28px; height: 28px; font-size: 0.7rem; }
    .ng-col-clue { width: 28px; }
    .ng-row-clue { height: 28px; }
    .ng-col-clue span, .ng-row-clue span { font-size: 0.62rem; }
}