:root {
    --cell-bg: #ffffff;
    --cell-border: #cbd5e1;
    --cell-hover: #f1f5f9;
    --x-color: #2563eb;
    --o-color: #dc2626;
    --win-bg: #fde68a;
}

@media (prefers-color-scheme: dark) {
    :root {
        --cell-bg: #10192b;
        --cell-border: #3a4a63;
        --cell-hover: #1f2c42;
        --x-color: #60a5fa;
        --o-color: #f87171;
        --win-bg: #78350f;
    }
}

.layout {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    align-items: flex-start;
    gap: 40px;
}

.game-area {
    text-align: center;
}

#lobby {
    width: 100%;
    max-width: 360px;
    background: var(--panel-bg);
    border: 1px solid var(--border);
    border-radius: 14px;
    box-shadow: 0 1px 3px var(--shadow);
    padding: 30px;
}

#lobby h2 {
    margin-top: 0;
    text-align: center;
    font-size: 20px;
}

#lobby hr {
    border: none;
    border-top: 1px solid var(--border);
    margin: 25px 0;
}

#lobby label {
    display: block;
    margin: 10px 0 5px;
    font-size: 14px;
}

#lobby input {
    width: 100%;
    padding: 10px;
    font-size: 16px;
    background: var(--input-bg);
    color: var(--text);
    border: 1px solid var(--input-border);
    border-radius: 8px;
}

#lobby button {
    width: 100%;
}

.lobby-message {
    margin-top: 15px;
    text-align: center;
    font-size: 14px;
}

.lobby-message.error {
    color: var(--error);
}

#keyDisplay {
    font-size: 15px;
    margin: 10px 0;
    padding: 10px;
    background: var(--input-bg);
    border: 1px dashed var(--input-border);
    border-radius: 4px;
    display: none;
}

#statsPanel {
    width: 100%;
    max-width: 360px;
    background: var(--panel-bg);
    border: 1px solid var(--border);
    border-radius: 14px;
    box-shadow: 0 1px 3px var(--shadow);
    padding: 24px 30px;
}

#statsPanel h2 {
    margin-top: 0;
    text-align: center;
    font-size: 20px;
}

#statsPanel select {
    width: 100%;
    padding: 8px;
    font-size: 15px;
    background: var(--input-bg);
    color: var(--text);
    border: 1px solid var(--input-border);
    border-radius: 8px;
    margin-bottom: 10px;
}

#board {
    display: grid;
    grid-template-columns: repeat(3, 100px);
    gap: 5px;
    justify-content: center;
}

.cell {
    width: 100px;
    height: 100px;
    font-size: 40px;
    font-family: inherit;
    font-weight: bold;
    border: 2px solid var(--cell-border);
    background: var(--cell-bg);
    color: var(--text);
    display: flex;
    justify-content: center;
    align-items: center;
    cursor: pointer;
    padding: 0;
    transition: background-color 0.15s ease, transform 0.1s ease;
}

.cell:hover:not(:disabled) {
    background: var(--cell-hover);
}

.cell:disabled {
    cursor: not-allowed;
}

.cell:focus-visible {
    outline: 3px solid var(--brand);
    outline-offset: -3px;
}

.cell[data-value="X"] {
    color: var(--x-color);
}

.cell[data-value="O"] {
    color: var(--o-color);
}

.cell.win {
    background: var(--win-bg);
}

.cell.mark-in {
    animation: mark-in 0.15s ease-out;
}

@keyframes mark-in {
    from {
        transform: scale(0.4);
        opacity: 0;
    }
    to {
        transform: scale(1);
        opacity: 1;
    }
}

.scorecard {
    width: 220px;
    background: var(--panel-bg);
    border: 1px solid var(--border);
    box-shadow: 0 1px 3px var(--shadow);
    padding: 20px;
    border-radius: 14px;
}

.scorecard h2 {
    margin-top: 0;
    text-align: center;
}

.score-row {
    display: flex;
    justify-content: space-between;
    font-size: 20px;
    margin: 12px 0;
}

#status, #player, #message {
    margin: 15px;
    font-size: 20px;
    min-height: 28px;
}

#status.your-turn {
    animation: pulse 1.2s ease-in-out infinite;
    font-weight: bold;
}

@keyframes pulse {
    0%, 100% {
        opacity: 1;
    }
    50% {
        opacity: 0.5;
    }
}

@media (max-width: 480px) {
    #board {
        grid-template-columns: repeat(3, 28vw);
    }

    .cell {
        width: 28vw;
        height: 28vw;
        font-size: 10vw;
    }
}