.fd-player{height:100svh;overflow:hidden;--paper-soft:var(--sh-paper);--paper-deep:var(--sh-soft);--ink-soft:var(--sh-muted);--ink-faint:var(--sh-muted);--hair:var(--sh-line);--accent-soft:var(--sh-soft);--sage-soft:var(--sh-sage);--warm-soft:var(--sh-butter);--fs-serif:var(--sans);--fs-sans:var(--sans);--fs-mono:var(--mono);--app-cream:var(--sh-bg);--app-paper:var(--sh-paper);--app-ink:var(--sh-ink);--app-ink-soft:var(--sh-muted);--app-ink-faint:var(--sh-muted);--app-muted-cream:var(--sh-muted);--app-hair:var(--sh-line);--app-lav-s:var(--sh-soft);--app-lav-text:var(--sh-accent);--app-sage-s:var(--sh-sage);--app-sage-text:var(--sh-green);--app-field-line:var(--sh-muted)}.fd-player .sh-course-label{max-width:370px;overflow:hidden;text-overflow:ellipsis}.fd-player .sh-stage{max-width:880px;min-height:0;overflow-y:auto;overscroll-behavior-y:contain;align-items:safe center;padding-top:30px;padding-bottom:30px;scrollbar-gutter:stable}.fd-player .sh-scene{min-height:340px;flex-shrink:0;display:flex;flex-direction:column;justify-content:center}.fd-player .sh-footer{position:relative;background:var(--sh-bg);flex:none;z-index:5}.fd-player .fd-kicker{display:block;margin-bottom:20px;font:13px var(--mono);color:var(--sh-muted);letter-spacing:.04em}.fd-player .fd-intro h1{font-size:clamp(32px,4vw,46px);line-height:1.2;max-width:780px}.fd-player .fd-intro .fd-copy{margin-top:26px}.fd-player .fd-reading{width:100%;max-width:760px;margin-inline:auto}.fd-player h2{font-size:30px;line-height:1.35;letter-spacing:-.35px;font-weight:550;text-wrap:balance}.fd-player .fd-copy{font-size:22px;line-height:1.7;color:var(--sh-ink);overflow-wrap:anywhere}.fd-player h2+.fd-copy{margin-top:22px}.fd-player .fd-copy p{white-space:pre-wrap}.fd-player .fd-copy p+p{margin-top:22px}.fd-player .fd-analogy code,.fd-player .fd-copy code{font-size:.86em;background:var(--sh-soft);padding:1px 5px;border-radius:4px}.fd-player .fd-analogy,.fd-player .fd-next{margin-top:28px;padding-left:18px;border-left:3px solid var(--sh-accent);color:var(--sh-muted);font-size:19px;line-height:1.6}.fd-player .fd-equation{overflow-x:auto;padding:24px;margin-top:26px;border-radius:14px;background:var(--sh-soft);font:20px/1.7 var(--mono)}.fd-player .fd-recap ul{display:grid;gap:18px;margin:30px 0 0;padding-left:24px;font-size:21px;line-height:1.6}.fd-player .fd-recap li::marker{color:var(--sh-accent)}.fd-player .fd-hint{margin:24px 0 0;color:var(--sh-muted)}.fd-player .fd-hint summary{min-height:44px;padding:10px 0;cursor:pointer;font-size:16px}.fd-player .fd-hint .fd-copy{font-size:18px;margin-top:6px}.fd-player .fd-activity{min-width:0;--sage:var(--sh-green);--warm:var(--rust);--cream:var(--sh-bg)}.fd-player .blk-split{display:grid;grid-template-columns:1fr;gap:22px}.fd-player .blk-visual{width:100%;max-width:600px;margin-inline:auto}.fd-player .reveal-h{font:500 26px/1.5 var(--sans)!important;color:var(--sh-ink)}.fd-player .reveal-b{font:20px/1.65 var(--sans);color:var(--sh-ink)}.fd-player .lq-ask{margin-bottom:26px}.fd-player .lq-prompt{font:500 24px/1.5 var(--sans)}.fd-player .lq-bubble{background:transparent;padding:0;border:0}.fd-player .lq-ask__tensor{display:none}.fd-player .lq-kicker{font-size:13px;margin-bottom:12px}.fd-player .lq-grid{gap:14px}.fd-player .lq-opt{border:1.5px solid var(--sh-line);background:var(--sh-paper);min-height:76px;padding:18px}.fd-player .lq-opt__label{font-size:20px;line-height:1.45}.fd-player .lq-opt--correct{background:var(--sh-sage);border-color:var(--sh-green)}.fd-player .lq-opt--wrong{background:var(--sh-butter);border-color:var(--rust)}.fd-player .lq-opt--dim{opacity:1}.fd-player .lq-strip__line{font-size:18px;line-height:1.55}.fd-player .lq-strip{border-radius:10px;padding:16px}.fd-player .lbtn{border:1px solid var(--sh-line);background:var(--sh-paper);color:var(--sh-ink);min-height:48px;border-radius:10px;font:17px var(--sans);padding:12px 20px}.fd-player .lbtn-accent{background:var(--sh-ink);color:var(--sh-bg);border-color:var(--sh-ink)}.fd-player .lq-bug-code{font-size:16px!important}.fd-player .lq-bug-code button{min-height:48px}.fd-player .lq-bug-line-text{min-width:0;white-space:pre-wrap!important;overflow-wrap:anywhere}.fd-player .act-h{font:500 28px/1.4 var(--sans)}.fd-player .act-note{font-size:19px;line-height:1.6}.fd-player .act-kick{font-size:14px}.fd-player .godeeper{border:1px solid var(--sh-line);padding:24px;border-radius:14px}.fd-player .godeeper summary{cursor:pointer;font-size:24px}.fd-player .fd-lab{display:grid;gap:22px;width:100%;min-width:0}.fd-player .fd-lab-head{display:grid;gap:12px}.fd-player .fd-lab-head p{font-size:19px;line-height:1.6;color:var(--sh-muted)}.fd-player .fd-progress{font:13px var(--mono);color:var(--sh-muted)}.fd-player .fd-board{border:1px solid var(--sh-line);border-radius:18px;background:var(--sh-paper);padding:28px;min-width:0}.fd-player .fd-board svg{display:block;max-width:100%;height:auto}.fd-player .fd-board table{width:100%;border-collapse:collapse;font-size:18px}.fd-player .fd-board td,.fd-player .fd-board th{padding:12px 10px;border-bottom:1px solid var(--sh-line);text-align:left}.fd-player .fd-choices{display:grid;gap:12px}.fd-player .fd-choice{background:var(--sh-paper);border:1.5px solid var(--sh-line);border-radius:12px;min-height:56px;padding:15px 20px;text-align:left;font-size:19px;line-height:1.5;transition:background .18s,border-color .18s}.fd-player .fd-choice:hover:not(:disabled),.fd-player .fd-choice[aria-pressed=true],.fd-player .fd-choice[data-selected=true]{border-color:var(--sh-accent);background:var(--sh-soft)}.fd-player .fd-choice[data-correct=true]{border-color:var(--sh-green);background:var(--sh-sage)}.fd-player .fd-action{justify-self:center;min-width:190px;min-height:50px;padding:12px 24px;border:1px solid var(--sh-ink);border-radius:11px;background:var(--sh-ink);color:var(--sh-bg);font-size:18px;font-weight:500;box-shadow:0 3px 0 var(--sh-muted)}.fd-player .fd-action:disabled{background:var(--disabled-bg);color:var(--sh-muted);border-color:var(--sh-line);box-shadow:none}.fd-player .fd-feedback{min-height:30px;font-size:18px;line-height:1.6;color:var(--sh-ink)}.fd-player .fd-code{font:17px/1.7 var(--mono);white-space:pre-wrap;overflow-wrap:anywhere}.fd-player [data-motion=paused] *,.fd-player[data-motion=paused] *{animation-play-state:paused!important}@media (max-width:1000px){.fd-player .sh-header{gap:18px;padding-inline:24px}.fd-player .sh-course-label{max-width:260px;padding-left:18px}.fd-player .sh-progress-track{width:170px}}@media (max-width:760px){.fd-player .sh-stage{padding:30px 22px}.fd-player .sh-scene{min-height:280px}.fd-player .sh-course-label{max-width:46vw}.fd-player h2{font-size:26px}.fd-player .fd-copy{font-size:20px;line-height:1.65}.fd-player .fd-board{padding:18px 14px;border-radius:13px}.fd-player .fd-board td,.fd-player .fd-board th{padding:9px 6px;font-size:16px}.fd-player .fd-choice{font-size:18px;padding:13px 16px}.fd-player .fd-lab{gap:18px}.fd-player .lq-prompt{font-size:23px}.fd-player .lq-opt__label{font-size:19px}}@media (prefers-reduced-motion:reduce){.fd-player *{animation:none!important;transition:none!important;scroll-behavior:auto!important}}