.merge-page {
    --merge-panel: var(--color-surface);
    --merge-board: var(--color-surface-muted);
    --merge-empty: color-mix(in srgb, var(--color-border) 24%, var(--color-surface));
    --merge-2: color-mix(in srgb, var(--color-secondary-accent) 16%, var(--color-surface));
    --merge-4: color-mix(in srgb, var(--color-secondary-accent) 34%, var(--color-surface));
    --merge-8: color-mix(in srgb, var(--petuja-orange) 32%, var(--color-surface));
    --merge-16: var(--color-secondary-accent);
    --merge-32: var(--color-accent);
    --merge-64: var(--petuja-orange);
    --merge-128: color-mix(in srgb, var(--petuja-orange) 74%, var(--color-accent));
    --merge-256: color-mix(in srgb, var(--color-accent) 76%, var(--petuja-orange));
    --merge-512: color-mix(in srgb, var(--color-secondary-accent) 60%, var(--color-accent));
    --merge-1024: color-mix(in srgb, var(--petuja-orange) 70%, var(--color-accent));
    --merge-2048: color-mix(in srgb, var(--petuja-orange) 52%, var(--color-accent));
}

.merge-page .merge-panel {
    display: grid;
    gap: clamp(1rem, 2vw, 1.4rem);
    width: min(100%, 38rem);
    margin-inline: auto;
    padding: clamp(0.9rem, 2vw, 1.5rem);
    overflow: hidden;
    background: var(--merge-panel);
}

.merge-toolbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
}

.merge-scoreboard {
    display: flex;
    flex-wrap: wrap;
    gap: 0.65rem;
}

.merge-score-card {
    display: grid;
    min-width: 6rem;
    gap: 0.15rem;
    padding: 0.55rem 0.75rem;
    border: 1px solid var(--color-border);
    border-radius: var(--tool-radius);
    background: var(--color-surface-muted);
}

.merge-score-label {
    color: var(--color-muted);
    font-size: 0.72rem;
    font-weight: 700;
    letter-spacing: 0.05em;
    text-transform: uppercase;
}

.merge-score-value {
    color: var(--color-text);
    font-size: clamp(1.25rem, 1rem + 1vw, 1.75rem);
    font-variant-numeric: tabular-nums;
    line-height: 1;
}

.merge-new-game {
    flex: 0 0 auto;
}

.merge-instructions,
.merge-status,
.merge-milestone,
.merge-rules p,
.merge-noscript {
    margin: 0;
}

.merge-instructions {
    color: var(--color-muted);
    font-size: 0.95rem;
    text-align: center;
}

.merge-board-shell {
    position: relative;
    width: min(100%, 35rem);
    margin-inline: auto;
}

.merge-board {
    position: relative;
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: clamp(0.34rem, 1.1vw, 0.65rem);
    width: 100%;
    aspect-ratio: 1;
    padding: clamp(0.4rem, 1.2vw, 0.75rem);
    border: 1px solid var(--color-border-strong);
    border-radius: calc(var(--tool-radius) + 0.15rem);
    background: var(--merge-board);
    outline: none;
    touch-action: none;
    user-select: none;
}

.merge-board:focus-visible {
    outline: 3px solid var(--color-focus);
    outline-offset: 3px;
}

.merge-cell {
    display: grid;
    min-width: 0;
    min-height: 0;
    place-items: center;
    overflow: hidden;
    border: 1px solid color-mix(in srgb, var(--color-border) 65%, transparent);
    border-radius: clamp(0.35rem, 1.2vw, 0.7rem);
    background: var(--merge-empty);
    color: transparent;
    font-size: clamp(1.15rem, 7.4vw, 2.7rem);
    font-variant-numeric: tabular-nums;
    font-weight: 850;
    line-height: 1;
    text-align: center;
    transition: background-color 140ms ease, color 140ms ease;
}

.merge-tile-layer {
    position: absolute;
    inset: 0;
    z-index: 2;
    pointer-events: none;
}

.merge-tile {
    position: absolute;
    display: grid;
    box-sizing: border-box;
    place-items: center;
    overflow: hidden;
    border: 1px solid color-mix(in srgb, var(--color-border) 65%, transparent);
    border-radius: clamp(0.35rem, 1.2vw, 0.7rem);
    background: var(--merge-empty);
    color: var(--color-text);
    font-size: clamp(1.15rem, 7.4vw, 2.7rem);
    font-variant-numeric: tabular-nums;
    font-weight: 850;
    line-height: 1;
    text-align: center;
    will-change: transform, opacity;
}

.merge-cell[data-value="2"], .merge-tile[data-value="2"] { background: var(--merge-2); color: var(--color-text); }
.merge-cell[data-value="4"], .merge-tile[data-value="4"] { background: var(--merge-4); color: var(--color-text); }
.merge-cell[data-value="8"], .merge-tile[data-value="8"] { background: var(--merge-8); color: var(--color-text); }
.merge-cell[data-value="16"], .merge-tile[data-value="16"] { background: var(--merge-16); color: #fff; }
.merge-cell[data-value="32"], .merge-tile[data-value="32"] { background: var(--merge-32); color: #fff; }
.merge-cell[data-value="64"], .merge-tile[data-value="64"] { background: var(--merge-64); color: #fff; }
.merge-cell[data-value="128"], .merge-tile[data-value="128"] { background: var(--merge-128); color: #fff; }
.merge-cell[data-value="256"], .merge-tile[data-value="256"] { background: var(--merge-256); color: #fff; }
.merge-cell[data-value="512"], .merge-tile[data-value="512"] { background: var(--merge-512); color: #fff; }
.merge-cell[data-value="1024"], .merge-tile[data-value="1024"] { background: var(--merge-1024); color: #fff; font-size: clamp(0.95rem, 5.2vw, 2.15rem); }
.merge-cell[data-value="2048"], .merge-tile[data-value="2048"] { background: var(--merge-2048); color: #fff; font-size: clamp(0.9rem, 4.8vw, 2rem); }
.merge-cell.merge-cell--high, .merge-tile.merge-tile--high { background: var(--color-accent); color: #fff; font-size: clamp(0.78rem, 4.4vw, 1.8rem); }

.merge-overlay {
    position: absolute;
    inset: clamp(0.4rem, 1.2vw, 0.75rem);
    z-index: 3;
    display: grid;
    place-content: center;
    justify-items: center;
    gap: 0.65rem;
    padding: 1.5rem;
    border-radius: clamp(0.35rem, 1.2vw, 0.7rem);
    background: color-mix(in srgb, var(--color-surface) 91%, transparent);
    text-align: center;
}

.merge-overlay[hidden] {
    display: none;
}

.merge-overlay__state,
.merge-overlay__message,
.merge-overlay__hint {
    margin: 0;
}

.merge-overlay__state {
    color: var(--color-accent);
    font-size: 0.78rem;
    font-weight: 800;
    letter-spacing: 0.1em;
    text-transform: uppercase;
}

.merge-overlay__message {
    color: var(--color-text);
    font-size: clamp(1.35rem, 1rem + 1vw, 2rem);
    font-weight: 850;
}

.merge-overlay__hint {
    max-width: 20rem;
    color: var(--color-muted);
}

.merge-milestone {
    padding: 0.7rem 0.85rem;
    border-inline-start: 3px solid var(--color-accent);
    border-radius: 0 var(--tool-radius) var(--tool-radius) 0;
    background: var(--color-accent-soft);
    color: var(--color-text);
    font-weight: 700;
    text-align: center;
}

.merge-milestone[hidden] {
    display: none;
}

.merge-status {
    min-height: 1.4em;
    color: var(--color-muted);
    font-size: 0.95rem;
    text-align: center;
}

.merge-rules {
    display: grid;
    gap: 0.45rem;
    padding-top: 0.85rem;
    border-top: 1px solid var(--color-border);
    color: var(--color-muted);
    text-align: center;
}

.merge-rules h3 {
    margin: 0;
    color: var(--color-text);
    font-size: 1rem;
}

.merge-noscript {
    color: var(--color-error);
}

@media (max-width: 560px) {
    .merge-toolbar {
        align-items: stretch;
        flex-direction: column;
    }

    .merge-scoreboard {
        width: 100%;
    }

    .merge-score-card {
        flex: 1 1 7rem;
    }

    .merge-new-game {
        width: 100%;
    }
}

@media (prefers-reduced-motion: reduce) {
    .merge-cell {
        transition: none;
    }

    .merge-tile {
        will-change: auto;
    }
}