.bkbg-g48-app {
    box-sizing: border-box;
    padding: 24px 20px;
    font-family: 'Helvetica Neue', Arial, sans-serif;
}

.bkbg-g48-title {
    margin: 0;
    font-family:      var(--bkg48-tt-font-family, inherit);
    font-size:        var(--bkg48-tt-font-size-d, 36px);
    font-weight:      var(--bkg48-tt-font-weight, 700);
    line-height:      var(--bkg48-tt-line-height-d, 1.1);
    text-transform:   var(--bkg48-tt-text-transform, none);
    font-style:       var(--bkg48-tt-font-style, normal);
    text-decoration:  var(--bkg48-tt-text-decoration, none);
    letter-spacing:   var(--bkg48-tt-letter-spacing-d);
    word-spacing:     var(--bkg48-tt-word-spacing-d);
}

.bkbg-g48-app h2.bkbg-g48-title {
    font-family:      var(--bkg48-tt-font-family, inherit);
    font-size:        var(--bkg48-tt-font-size-d, 36px);
    font-weight:      var(--bkg48-tt-font-weight, 700);
    line-height:      var(--bkg48-tt-line-height-d, 1.1);
    text-transform:   var(--bkg48-tt-text-transform, none);
    font-style:       var(--bkg48-tt-font-style, normal);
    text-decoration:  var(--bkg48-tt-text-decoration, none);
    letter-spacing:   var(--bkg48-tt-letter-spacing-d);
    word-spacing:     var(--bkg48-tt-word-spacing-d);
}

.bkbg-g48-subtitle {
    margin: 2px 0 0;
    opacity: 0.75;
    font-family:      var(--bkg48-st-font-family, inherit);
    font-size:        var(--bkg48-st-font-size-d, 15px);
    font-weight:      var(--bkg48-st-font-weight, 400);
    line-height:      var(--bkg48-st-line-height-d, 1.5);
    text-transform:   var(--bkg48-st-text-transform, none);
    font-style:       var(--bkg48-st-font-style, normal);
    text-decoration:  var(--bkg48-st-text-decoration, none);
    letter-spacing:   var(--bkg48-st-letter-spacing-d);
    word-spacing:     var(--bkg48-st-word-spacing-d);
}

/* ---- Header row ---- */

.bkbg-g48-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 10px;
    margin-bottom: 14px;
}

/* ---- Score boxes ---- */

.bkbg-g48-scores {
    display: flex;
    gap: 8px;
    align-items: center;
    flex-wrap: wrap;
}

.bkbg-g48-score-box {
    border-radius: 6px;
    padding: 6px 14px;
    text-align: center;
    min-width: 70px;
}

.bkbg-g48-score-label {
    font-size: 11px;
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    margin-bottom: 2px;
    opacity: 0.8;
}

.bkbg-g48-score-value {
    font-size: 22px;
    font-weight: 700;
}

/* ---- New Game button ---- */

.bkbg-g48-new-btn {
    border: none;
    border-radius: 6px;
    padding: 9px 16px;
    font-weight: 700;
    font-size: 14px;
    cursor: pointer;
    color: #fff;
    transition: filter 0.15s, transform 0.1s;
}

.bkbg-g48-new-btn:hover {
    filter: brightness(1.1);
    transform: translateY(-1px);
}

/* ---- Board ---- */

.bkbg-g48-board-wrap {
    display: flex;
    justify-content: center;
    position: relative;
}

.bkbg-g48-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    position: relative;
    user-select: none;
    touch-action: none;
}

/* ---- Tiles ---- */

.bkbg-g48-tile {
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-family: 'Helvetica Neue', Arial, sans-serif;
    transition: background 0.1s, color 0.1s;
}

.bkbg-g48-tile.bkbg-g48-pop {
    animation: bkbg-g48-pop 0.12s ease;
}

.bkbg-g48-tile.bkbg-g48-new {
    animation: bkbg-g48-appear 0.15s ease;
}

@keyframes bkbg-g48-pop {
    0%   { transform: scale(1); }
    50%  { transform: scale(1.15); }
    100% { transform: scale(1); }
}

@keyframes bkbg-g48-appear {
    0%   { transform: scale(0.6); opacity: 0; }
    100% { transform: scale(1);   opacity: 1; }
}

/* ---- Overlay (you win / game over) ---- */

.bkbg-g48-overlay {
    position: absolute;
    inset: 0;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    border-radius: inherit;
    animation: bkbg-g48-fade-in 0.35s ease;
    z-index: 10;
}

@keyframes bkbg-g48-fade-in {
    from { opacity: 0; }
    to   { opacity: 1; }
}

.bkbg-g48-overlay-msg {
    font-size: 32px;
    font-weight: 700;
    margin-bottom: 16px;
}

.bkbg-g48-overlay-sub {
    font-size: 16px;
    margin-bottom: 20px;
    opacity: 0.85;
}

/* ---- Hint text ---- */

.bkbg-g48-hint {
    text-align: center;
    font-size: 13px;
    margin-top: 12px;
    opacity: 0.55;
}

/* ---- Responsive ---- */

@media (max-width: 480px) {
    .bkbg-g48-app { padding: 16px 10px; }
    .bkbg-g48-header { gap: 8px; }
    .bkbg-g48-score-value { font-size: 18px; }
}

/* ---- Typography responsive: Tablet ---- */
@media (max-width: 1024px) {
    .bkbg-g48-title,
    .bkbg-g48-app h2.bkbg-g48-title {
        font-size:       var(--bkg48-tt-font-size-t, var(--bkg48-tt-font-size-d, 36px));
        line-height:     var(--bkg48-tt-line-height-t, var(--bkg48-tt-line-height-d, 1.1));
        letter-spacing:  var(--bkg48-tt-letter-spacing-t, var(--bkg48-tt-letter-spacing-d));
        word-spacing:    var(--bkg48-tt-word-spacing-t, var(--bkg48-tt-word-spacing-d));
    }
    .bkbg-g48-subtitle {
        font-size:       var(--bkg48-st-font-size-t, var(--bkg48-st-font-size-d, 15px));
        line-height:     var(--bkg48-st-line-height-t, var(--bkg48-st-line-height-d, 1.5));
        letter-spacing:  var(--bkg48-st-letter-spacing-t, var(--bkg48-st-letter-spacing-d));
        word-spacing:    var(--bkg48-st-word-spacing-t, var(--bkg48-st-word-spacing-d));
    }
}

/* ---- Typography responsive: Mobile ---- */
@media (max-width: 767px) {
    .bkbg-g48-title,
    .bkbg-g48-app h2.bkbg-g48-title {
        font-size:       var(--bkg48-tt-font-size-m, var(--bkg48-tt-font-size-t, var(--bkg48-tt-font-size-d, 36px)));
        line-height:     var(--bkg48-tt-line-height-m, var(--bkg48-tt-line-height-t, var(--bkg48-tt-line-height-d, 1.1)));
        letter-spacing:  var(--bkg48-tt-letter-spacing-m, var(--bkg48-tt-letter-spacing-t, var(--bkg48-tt-letter-spacing-d)));
        word-spacing:    var(--bkg48-tt-word-spacing-m, var(--bkg48-tt-word-spacing-t, var(--bkg48-tt-word-spacing-d)));
    }
    .bkbg-g48-subtitle {
        font-size:       var(--bkg48-st-font-size-m, var(--bkg48-st-font-size-t, var(--bkg48-st-font-size-d, 15px)));
        line-height:     var(--bkg48-st-line-height-m, var(--bkg48-st-line-height-t, var(--bkg48-st-line-height-d, 1.5)));
        letter-spacing:  var(--bkg48-st-letter-spacing-m, var(--bkg48-st-letter-spacing-t, var(--bkg48-st-letter-spacing-d)));
        word-spacing:    var(--bkg48-st-word-spacing-m, var(--bkg48-st-word-spacing-t, var(--bkg48-st-word-spacing-d)));
    }
}