/* ===== 朗读流利度计时 reading-fluency ===== */
.rf-seg { display: grid; grid-auto-flow: column; grid-auto-columns: 1fr; gap: 8px; }
.rf-seg button {
    height: 41px;
    border-radius: 12px;
    border: 1px solid var(--c-border);
    background: var(--c-surface-soft);
    color: var(--c-text-sub);
    font-family: inherit;
    font-size: 13px;
    font-weight: 700;
    cursor: pointer;
    padding: 0 6px;
    transition: all .16s ease;
}
.rf-seg button:hover { border-color: #1f9d43; color: #1f9d43; }
.rf-seg button.is-active {
    background: linear-gradient(135deg, rgba(31,157,67,.16), rgba(31,157,67,.07));
    border-color: rgba(31,157,67,.55);
    color: #187933;
}
.rf-start { margin-top: 4px; height: 48px; font-weight: 800; }
.rf-textarea {
    width: 100%;
    min-height: 150px;
    padding: 12px 14px;
    font-size: 14px;
    font-family: inherit;
    line-height: 1.8;
    color: var(--c-text);
    background: var(--c-surface-soft);
    border: 1px solid var(--c-border);
    border-radius: 12px;
    outline: none;
    resize: vertical;
}
.rf-textarea:focus { border-color: #1f9d43; box-shadow: 0 0 0 3px rgba(31,157,67,.14); }

/* AI 短文 */
.rf-passage-text {
    font-size: 17px;
    line-height: 2.2;
    color: var(--c-text);
    padding: 14px 16px;
    border-radius: 12px;
    background: var(--c-surface-soft);
    border: 1px solid var(--c-border);
    margin: 10px 0;
    user-select: none;
}
.rf-passage-title { font-size: 14.5px; font-weight: 800; color: var(--c-text); }
.rf-passage-tip {
    font-size: 12.5px;
    line-height: 1.8;
    color: #187933;
    background: rgba(31,157,67,.08);
    border: 1px dashed rgba(31,157,67,.4);
    border-radius: 10px;
    padding: 10px 12px;
    margin-bottom: 10px;
}
.rf-char {
    cursor: default;
    border-radius: 4px;
    padding: 0 1px;
}
.rf-passage-text.is-marking .rf-char { cursor: pointer; }
.rf-passage-text.is-marking .rf-char:hover { background: rgba(31,157,67,.25); }
.rf-char.is-read { color: #1f9d43; }
.rf-char.is-mark { background: #1f9d43; color: #fff; }

/* 计时区 */
.rf-timer-zone { text-align: center; padding: 14px 0 20px; }
.rf-timer-label { font-size: 13px; color: var(--c-text-muted); margin-bottom: 6px; }
.rf-timer-num {
    font-size: 72px;
    font-weight: 900;
    line-height: 1.1;
    color: #187933;
    font-variant-numeric: tabular-nums;
}
.rf-timer-num.is-run { color: #1f9d43; }
.rf-timer-num.is-end { color: #e0447c; }
#rfStop { margin-top: 12px; height: 48px; font-weight: 800; }

.rf-err-line { display: flex; gap: 8px; }
.rf-err-line input { flex: 1; }
.rf-err-line .btn-primary { white-space: nowrap; height: 43px; }
.rf-err-line .calc-input { padding-right: 14px; }

.rf-level-pill { font-weight: 900; }
.rf-level-0 { color: #e0447c; }
.rf-level-1 { color: #d98a00; }
.rf-level-2 { color: #0a96d4; }
.rf-level-3 { color: #1f9d43; }

/* 历史 */
.rf-history { display: flex; flex-direction: column; gap: 8px; }
.rf-hi {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 8px;
    padding: 9px 12px;
    border-radius: 10px;
    border: 1px solid var(--c-border);
    background: var(--c-surface-soft);
    font-size: 12.5px;
}
.rf-hi b { font-size: 14px; }
.rf-hi .rf-hi-sub { color: var(--c-text-muted); font-size: 11.5px; }
.rf-hi .rf-hi-del { border: none; background: none; cursor: pointer; color: var(--c-text-muted); font-size: 12px; }
.rf-hi .rf-hi-del:hover { color: #e0447c; }
.rf-history-empty { font-size: 12.5px; color: var(--c-text-muted); padding: 6px 0; }

@media (max-width: 1000px) {
    .rf-timer-num { font-size: 58px; }
}