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path[data-link-complete=yes]{stroke:var(--line-strong)}.power-chain-links marker path{fill:var(--emphasis)}.power-chain-omission{height:var(--chain-row-height);font-size:var(--text-support);border-block:1px dashed var(--line-strong);place-items:center;display:grid}.power-chain-count{font-size:var(--text-support)}.power-sum-final{font-size:clamp(1.2rem,4vw,1.65rem);font-weight:700}.power-sum-pair,.power-sum-result{border:1px solid var(--line-strong);background:var(--surface-soft);border-radius:var(--radius-small);gap:.5rem;min-width:0;padding:.7rem;display:grid}.power-sum-patterns{grid-template-columns:repeat(2,minmax(0,1fr));gap:.5rem;display:grid}.power-sum-patterns button{border:1px solid var(--line-strong);background:var(--surface);min-height:48px;color:var(--ink);font:inherit;cursor:pointer;border-radius:var(--radius-small);padding:.6rem}.power-sum-patterns [aria-pressed=true]{outline:2px solid var(--emphasis);outline-offset:-2px}.power-sum-block>.power-sum-answer{width:auto;margin:0}.power-sum-answer>.power-sum-block{padding:.7rem}.power-sum-static{margin-block:1rem}@media (width<=500px){.power-chain{--chain-source:3.25rem;--chain-equal:1.15rem}.power-chain-original{font-size:1.2rem}.power-chain-source{padding:.5rem}.power-chain-rule{font-size:1.05rem}.power-chain-heading{font-size:.85rem}}.protected-video{max-width:var(--reading-width);margin-block:var(--space-5);border:1px solid var(--line);border-radius:var(--radius);background:var(--surface)}.protected-video-cover{align-items:center;gap:var(--space-4);width:100%;min-height:110px;padding:var(--space-5);color:var(--ink);background:var(--surface-soft);font:inherit;text-align:left;cursor:pointer;border-radius:inherit;border:0;display:flex}.protected-video-cover[hidden],.protected-video video[hidden]{display:none}.protected-video-cover strong,.protected-video-cover span span{display:block}.protected-video-cover span span{margin-top:var(--space-2);font-size:var(--text-support);color:var(--muted)}.protected-video-play{flex:0 0 40px;font-size:28px}.protected-video-session{padding:var(--space-4)}.protected-video-toolbar{justify-content:space-between;align-items:center;gap:var(--space-3);margin-bottom:var(--space-4);display:flex}.protected-video-toolbar .button{flex-shrink:0}.protected-video-input{align-items:stretch;gap:var(--space-3);margin-top:var(--space-2);flex-wrap:wrap;display:flex}.protected-video-input input{min-width:0;min-height:44px;padding:var(--space-2) var(--space-3);border:1px solid var(--line-strong);border-radius:var(--radius-small);background:var(--surface);color:var(--ink);font:inherit;flex:140px}.protected-video .button{min-height:44px}.protected-video-status{color:var(--muted);font-size:var(--text-support)}.protected-video video{background:#000;width:100%;max-width:360px;max-height:72svh;margin-inline:auto;display:block}.protected-video-cover:focus-visible,.protected-video-input 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button:focus-visible,.protected-video .playback-speed-options button[aria-pressed=true]{background:#414141}@media (width<=360px){.protected-video-cover{padding:var(--space-4);gap:var(--space-3)}.protected-video-toolbar{align-items:flex-start}}