.bkbg-rt-app {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    -webkit-font-smoothing: antialiased;
}
.bkbg-rt-card {
    margin: 0 auto;
    padding: 36px 32px;
    border-radius: 16px;
    box-shadow: 0 4px 32px rgba(0,0,0,0.08);
}
.bkbg-rt-card h2.bkbg-rt-title {
    font-family: var(--bkbgrt-tt-font-family, inherit);
    font-size: var(--bkbgrt-tt-font-size-d, 26px);
    font-weight: var(--bkbgrt-tt-font-weight, 800);
    font-style: var(--bkbgrt-tt-font-style, normal);
    text-decoration: var(--bkbgrt-tt-text-decoration, none);
    text-transform: var(--bkbgrt-tt-text-transform, none);
    line-height: var(--bkbgrt-tt-line-height-d, 1.2);
    letter-spacing: var(--bkbgrt-tt-letter-spacing-d, normal);
    word-spacing: var(--bkbgrt-tt-word-spacing-d, normal);
    text-align: center;
    margin: 0 0 8px;
}
.bkbg-rt-subtitle {
    text-align: center;
    font-size: 15px;
    margin: 0 0 24px;
}
.bkbg-rt-label {
    font-size: 12px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 8px;
    display: block;
}
/* Pattern row */
.bkbg-rt-pattern-row {
    margin-bottom: 18px;
}
.bkbg-rt-pattern-wrap {
    display: flex;
    align-items: center;
    border-radius: 10px;
    padding: 2px 14px;
    gap: 4px;
    margin-bottom: 6px;
}
.bkbg-rt-slash {
    font-size: 22px;
    font-weight: 900;
    font-family: 'SF Mono', Consolas, 'Courier New', monospace;
    user-select: none;
    flex-shrink: 0;
}
.bkbg-rt-pattern-input {
    flex: 1;
    border: none;
    outline: none;
    padding: 12px 6px;
    font-family: 'SF Mono', Consolas, 'Courier New', monospace;
}
.bkbg-rt-flags-input {
    width: 48px;
    border: none;
    outline: none;
    padding: 12px 4px;
    font-family: 'SF Mono', Consolas, 'Courier New', monospace;
    font-weight: 700;
}
.bkbg-rt-pattern-input,
.bkbg-rt-flags-input {
    font-family: var(--bkbgrt-et-font-family, 'SF Mono', Consolas, 'Courier New', monospace);
    font-size: var(--bkbgrt-et-font-size-d, 14px);
    font-weight: var(--bkbgrt-et-font-weight, 400);
    font-style: var(--bkbgrt-et-font-style, normal);
    line-height: var(--bkbgrt-et-line-height-d, 1.6);
    letter-spacing: var(--bkbgrt-et-letter-spacing-d, normal);
    word-spacing: var(--bkbgrt-et-word-spacing-d, normal);
}
.bkbg-rt-error {
    font-size: 13px;
    font-weight: 600;
    padding: 6px 10px;
    background: #fef2f2;
    border-radius: 6px;
    margin-bottom: 6px;
}
/* Flag toggles */
.bkbg-rt-flags-row {
    display: flex;
    gap: 6px;
    flex-wrap: wrap;
}
.bkbg-rt-flag-btn {
    display: flex;
    align-items: center;
    gap: 5px;
    padding: 5px 12px;
    border-radius: 99px;
    border: none;
    cursor: pointer;
    font-size: 12px;
    font-family: inherit;
    transition: background 0.15s, color 0.15s;
}
.bkbg-rt-flag-btn strong {
    font-family: 'SF Mono', Consolas, monospace;
    font-size: 13px;
}
.bkbg-rt-flag-btn span {
    font-size: 11px;
    opacity: 0.85;
}
/* Test string */
.bkbg-rt-section { margin-bottom: 14px; }
.bkbg-rt-textarea {
    width: 100%;
    display: block;
    padding: 14px 16px;
    border: 1.5px solid #e5e7eb;
    border-radius: 10px;
    font-family: var(--bkbgrt-et-font-family, 'SF Mono', Consolas, 'Courier New', monospace);
    font-size: var(--bkbgrt-et-font-size-d, 14px);
    font-weight: var(--bkbgrt-et-font-weight, 400);
    font-style: var(--bkbgrt-et-font-style, normal);
    line-height: var(--bkbgrt-et-line-height-d, 1.6);
    letter-spacing: var(--bkbgrt-et-letter-spacing-d, normal);
    word-spacing: var(--bkbgrt-et-word-spacing-d, normal);
    resize: vertical;
    outline: none;
    box-sizing: border-box;
    transition: border-color 0.15s;
}
.bkbg-rt-textarea:focus { border-color: #f59e0b; }
/* Stats bar */
.bkbg-rt-stats {
    padding: 10px 16px;
    border-radius: 8px;
    font-size: 13px;
    font-weight: 600;
    margin-bottom: 16px;
    display: flex;
    gap: 20px;
    flex-wrap: wrap;
}
/* Highlighted output */
.bkbg-rt-output {
    font-family: 'SF Mono', Consolas, 'Courier New', monospace;
    line-height: 1.8;
    border-radius: 10px;
    padding: 14px 16px;
    white-space: pre-wrap;
    word-break: break-all;
    border: 1.5px solid #e5e7eb;
    margin-bottom: 16px;
}
.bkbg-rt-match {
    border-radius: 3px;
    padding: 1px 2px;
    border-bottom: 2px solid;
    cursor: default;
    position: relative;
}
/* Matches list */
.bkbg-rt-matches { margin-top: 4px; }
.bkbg-rt-matches-title {
    font-size: 13px;
    font-weight: 800;
    margin-bottom: 10px;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}
.bkbg-rt-match-badge {
    display: flex;
    align-items: baseline;
    gap: 8px;
    padding: 8px 12px;
    border: 1.5px solid;
    border-radius: 8px;
    margin-bottom: 6px;
    font-family: 'SF Mono', Consolas, monospace;
    font-size: 13px;
    flex-wrap: wrap;
}
.bkbg-rt-match-idx {
    font-weight: 800;
    flex-shrink: 0;
    font-size: 11px;
}
.bkbg-rt-match-val {
    font-weight: 600;
    flex: 1;
    word-break: break-all;
}
.bkbg-rt-match-groups {
    font-size: 11px;
    opacity: 0.7;
}
.bkbg-rt-more {
    font-size: 13px;
    font-style: italic;
    padding: 6px;
    text-align: center;
}
@media (max-width: 1024px) {
    .bkbg-rt-card h2.bkbg-rt-title {
        font-size: var(--bkbgrt-tt-font-size-t, var(--bkbgrt-tt-font-size-d, 26px));
        line-height: var(--bkbgrt-tt-line-height-t, var(--bkbgrt-tt-line-height-d, 1.2));
        letter-spacing: var(--bkbgrt-tt-letter-spacing-t, var(--bkbgrt-tt-letter-spacing-d, normal));
        word-spacing: var(--bkbgrt-tt-word-spacing-t, var(--bkbgrt-tt-word-spacing-d, normal));
    }
    .bkbg-rt-pattern-input,
    .bkbg-rt-flags-input,
    .bkbg-rt-textarea {
        font-size: var(--bkbgrt-et-font-size-t, var(--bkbgrt-et-font-size-d, 14px));
        line-height: var(--bkbgrt-et-line-height-t, var(--bkbgrt-et-line-height-d, 1.6));
        letter-spacing: var(--bkbgrt-et-letter-spacing-t, var(--bkbgrt-et-letter-spacing-d, normal));
        word-spacing: var(--bkbgrt-et-word-spacing-t, var(--bkbgrt-et-word-spacing-d, normal));
    }
}
@media (max-width: 767px) {
    .bkbg-rt-card h2.bkbg-rt-title {
        font-size: var(--bkbgrt-tt-font-size-m, var(--bkbgrt-tt-font-size-t, var(--bkbgrt-tt-font-size-d, 26px)));
        line-height: var(--bkbgrt-tt-line-height-m, var(--bkbgrt-tt-line-height-t, var(--bkbgrt-tt-line-height-d, 1.2)));
        letter-spacing: var(--bkbgrt-tt-letter-spacing-m, var(--bkbgrt-tt-letter-spacing-t, var(--bkbgrt-tt-letter-spacing-d, normal)));
        word-spacing: var(--bkbgrt-tt-word-spacing-m, var(--bkbgrt-tt-word-spacing-t, var(--bkbgrt-tt-word-spacing-d, normal)));
    }
    .bkbg-rt-pattern-input,
    .bkbg-rt-flags-input,
    .bkbg-rt-textarea {
        font-size: var(--bkbgrt-et-font-size-m, var(--bkbgrt-et-font-size-t, var(--bkbgrt-et-font-size-d, 14px)));
        line-height: var(--bkbgrt-et-line-height-m, var(--bkbgrt-et-line-height-t, var(--bkbgrt-et-line-height-d, 1.6)));
        letter-spacing: var(--bkbgrt-et-letter-spacing-m, var(--bkbgrt-et-letter-spacing-t, var(--bkbgrt-et-letter-spacing-d, normal)));
        word-spacing: var(--bkbgrt-et-word-spacing-m, var(--bkbgrt-et-word-spacing-t, var(--bkbgrt-et-word-spacing-d, normal)));
    }
}
@media (max-width: 560px) {
    .bkbg-rt-card { padding: 22px 14px; }
    .bkbg-rt-flag-btn span { display: none; }
}