.bkbg-cb-app {
    font-family: system-ui, -apple-system, sans-serif;
    box-sizing: border-box;
}

.bkbg-cb-wrap {
    border-radius: 12px;
    padding: 28px;
    margin: 0 auto;
}

.bkbg-cb-title {
    font-family: var(--bkbg-cb-ttl-font-family, inherit);
    font-size: var(--bkbg-cb-ttl-font-size-d, 26px);
    font-weight: var(--bkbg-cb-ttl-font-weight, 700);
    font-style: var(--bkbg-cb-ttl-font-style, normal);
    text-transform: var(--bkbg-cb-ttl-text-transform, none);
    text-decoration: var(--bkbg-cb-ttl-text-decoration, none);
    line-height: var(--bkbg-cb-ttl-line-height-d, 1.2);
    letter-spacing: var(--bkbg-cb-ttl-letter-spacing-d, normal);
    word-spacing: var(--bkbg-cb-ttl-word-spacing-d, normal);
    margin: 0 0 6px;
}

.bkbg-cb-subtitle {
    font-family: var(--bkbg-cb-sub-font-family, inherit);
    font-size: var(--bkbg-cb-sub-font-size-d, 15px);
    font-weight: var(--bkbg-cb-sub-font-weight, normal);
    font-style: var(--bkbg-cb-sub-font-style, normal);
    text-transform: var(--bkbg-cb-sub-text-transform, none);
    text-decoration: var(--bkbg-cb-sub-text-decoration, none);
    line-height: var(--bkbg-cb-sub-line-height-d, 1.5);
    letter-spacing: var(--bkbg-cb-sub-letter-spacing-d, normal);
    word-spacing: var(--bkbg-cb-sub-word-spacing-d, normal);
    margin: 0 0 22px;
}

.bkbg-cb-card {
    border-radius: 10px;
    padding: 20px;
    margin-bottom: 16px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.06);
}

/* Presets */
.bkbg-cb-presets {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
    border-radius: 10px;
    padding: 16px;
    margin-bottom: 16px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.05);
}

.bkbg-cb-preset-btn {
    border: none;
    border-radius: 6px;
    padding: 6px 14px;
    font-size: 12px;
    font-weight: 500;
    cursor: pointer;
    transition: background 0.15s, color 0.15s;
}

.bkbg-cb-preset-btn:hover { opacity: 0.85; }

/* Fields row */
.bkbg-cb-fields {
    display: flex;
    gap: 10px;
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: 16px;
}

.bkbg-cb-field-col {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 6px;
}

.bkbg-cb-field-input {
    border-radius: 8px;
    padding: 10px;
    text-align: center;
    font-size: 20px;
    font-family: 'Courier New', Courier, monospace;
    font-weight: 700;
    width: 70px;
    border: 2px solid transparent;
    outline: none;
    transition: border-color 0.2s;
    -moz-appearance: textfield;
}

.bkbg-cb-field-input::-webkit-outer-spin-button,
.bkbg-cb-field-input::-webkit-inner-spin-button { -webkit-appearance: none; margin: 0; }

.bkbg-cb-field-input:focus { border-color: currentColor; }

.bkbg-cb-field-label {
    font-size: 11px;
    font-weight: 600;
    opacity: 0.65;
    text-align: center;
}

/* Expression display */
.bkbg-cb-expr-display {
    border-radius: 8px;
    padding: 14px;
    text-align: center;
    font-family: 'Courier New', Courier, monospace;
    font-size: 24px;
    font-weight: 700;
    letter-spacing: 0.12em;
    margin-bottom: 14px;
    user-select: all;
}

/* Actions */
.bkbg-cb-actions {
    display: flex;
    gap: 10px;
    justify-content: center;
    flex-wrap: wrap;
}

.bkbg-cb-btn {
    border: none;
    border-radius: 8px;
    padding: 10px 22px;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    transition: filter 0.15s;
    color: #fff;
}

.bkbg-cb-btn:hover { filter: brightness(0.9); }
.bkbg-cb-btn-outline { background: transparent !important; border: 2px solid; }

/* Description */
.bkbg-cb-desc-card {
    border-radius: 10px;
    padding: 16px 20px;
    margin-bottom: 16px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.05);
    border-left-width: 4px;
    border-left-style: solid;
}

.bkbg-cb-desc-label {
    font-size: 11px;
    font-weight: 700;
    opacity: 0.6;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    margin-bottom: 6px;
}

.bkbg-cb-desc-text {
    font-size: 16px;
    line-height: 1.5;
}

/* Error */
.bkbg-cb-error {
    font-size: 13px;
    color: #ef4444;
    background: #fef2f2;
    border: 1px solid #fecaca;
    border-radius: 6px;
    padding: 8px 14px;
    margin-bottom: 12px;
}

/* Next runs */
.bkbg-cb-next-title {
    font-size: 14px;
    font-weight: 700;
    margin-bottom: 10px;
}

.bkbg-cb-next-item {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 9px 0;
    border-bottom: 1px solid #f3f4f6;
    font-size: 14px;
}

.bkbg-cb-next-item:last-child { border-bottom: none; }

.bkbg-cb-next-arrow { font-weight: 700; font-size: 16px; }

.bkbg-cb-next-relative {
    margin-left: auto;
    font-size: 11px;
    opacity: 0.6;
    white-space: nowrap;
}

.bkbg-cb-copy-msg {
    font-size: 13px;
    text-align: center;
    height: 20px;
    transition: opacity 0.3s;
    opacity: 0;
    margin-top: 8px;
}

/* Typography responsive */
@media (max-width: 1024px) {
    .bkbg-cb-title {
        font-size: var(--bkbg-cb-ttl-font-size-t, var(--bkbg-cb-ttl-font-size-d, 26px));
        line-height: var(--bkbg-cb-ttl-line-height-t, var(--bkbg-cb-ttl-line-height-d, 1.2));
        letter-spacing: var(--bkbg-cb-ttl-letter-spacing-t, var(--bkbg-cb-ttl-letter-spacing-d, normal));
        word-spacing: var(--bkbg-cb-ttl-word-spacing-t, var(--bkbg-cb-ttl-word-spacing-d, normal));
    }
    .bkbg-cb-subtitle {
        font-size: var(--bkbg-cb-sub-font-size-t, var(--bkbg-cb-sub-font-size-d, 15px));
        line-height: var(--bkbg-cb-sub-line-height-t, var(--bkbg-cb-sub-line-height-d, 1.5));
        letter-spacing: var(--bkbg-cb-sub-letter-spacing-t, var(--bkbg-cb-sub-letter-spacing-d, normal));
        word-spacing: var(--bkbg-cb-sub-word-spacing-t, var(--bkbg-cb-sub-word-spacing-d, normal));
    }
}
@media (max-width: 767px) {
    .bkbg-cb-title {
        font-size: var(--bkbg-cb-ttl-font-size-m, var(--bkbg-cb-ttl-font-size-t, var(--bkbg-cb-ttl-font-size-d, 26px)));
        line-height: var(--bkbg-cb-ttl-line-height-m, var(--bkbg-cb-ttl-line-height-t, var(--bkbg-cb-ttl-line-height-d, 1.2)));
        letter-spacing: var(--bkbg-cb-ttl-letter-spacing-m, var(--bkbg-cb-ttl-letter-spacing-t, var(--bkbg-cb-ttl-letter-spacing-d, normal)));
        word-spacing: var(--bkbg-cb-ttl-word-spacing-m, var(--bkbg-cb-ttl-word-spacing-t, var(--bkbg-cb-ttl-word-spacing-d, normal)));
    }
    .bkbg-cb-subtitle {
        font-size: var(--bkbg-cb-sub-font-size-m, var(--bkbg-cb-sub-font-size-t, var(--bkbg-cb-sub-font-size-d, 15px)));
        line-height: var(--bkbg-cb-sub-line-height-m, var(--bkbg-cb-sub-line-height-t, var(--bkbg-cb-sub-line-height-d, 1.5)));
        letter-spacing: var(--bkbg-cb-sub-letter-spacing-m, var(--bkbg-cb-sub-letter-spacing-t, var(--bkbg-cb-sub-letter-spacing-d, normal)));
        word-spacing: var(--bkbg-cb-sub-word-spacing-m, var(--bkbg-cb-sub-word-spacing-t, var(--bkbg-cb-sub-word-spacing-d, normal)));
    }
}

.bkbg-cb-copy-msg.bkbg-cb-show { opacity: 1; }

@media (max-width: 480px) {
    .bkbg-cb-wrap { padding: 16px; }
    .bkbg-cb-field-input { width: 56px; font-size: 17px; }
    .bkbg-cb-expr-display { font-size: 18px; }
}