._lesson_1ac6r_1{--ink:#28373d;--muted:#53636b;--line:#d3dce1;--gold:#866028;--teal:#176b5c;--panel:#f8fafb;--soft:#edf2f5;--button:#e8eef2;--selection:#d9eee4;--match:#f3ecdc;max-width:1100px;color:var(--ink);margin:0 auto;padding:30px 28px 100px}.dark ._lesson_1ac6r_1{--ink:#e4e7e8;--muted:#b0b8be;--line:#39424c;--gold:#efc778;--teal:#7ad8c4;--panel:#14191d;--soft:#1d252b;--button:#252f37;--selection:#244238;--match:#3d3423}._lesson_1ac6r_1 *{box-sizing:border-box}._back_1ac6r_4{color:var(--muted);align-items:center;gap:8px;margin-bottom:32px;font-size:14px;display:inline-flex}._header_1ac6r_5{max-width:900px;padding-bottom:36px}._eyebrow_1ac6r_6{color:var(--gold);letter-spacing:.12em;text-transform:uppercase;font-size:12px}._header_1ac6r_5 h1{letter-spacing:-.03em;margin:15px 0 25px;font-size:clamp(31px,4.8vw,50px);font-weight:550;line-height:1.2}._lesson_1ac6r_1 p{max-width:900px;margin:17px 0;font-size:16px;line-height:1.95}._nav_1ac6r_9{border-top:1px solid var(--line);border-bottom:1px solid var(--line);color:var(--muted);flex-wrap:wrap;gap:10px 22px;padding:20px 0;font-size:14px;line-height:1.8;display:flex}._nav_1ac6r_9 a:hover,._back_1ac6r_4:hover{color:var(--gold)}._section_1ac6r_11{padding-top:52px;scroll-margin-top:90px}._section_1ac6r_11+._section_1ac6r_11{border-top:1px solid var(--line);margin-top:42px}._number_1ac6r_13{color:var(--gold);font-variant-numeric:tabular-nums;letter-spacing:.12em;font-size:13px}._section_1ac6r_11 h2{margin:10px 0 24px;font-size:clamp(24px,3vw,32px);font-weight:550;line-height:1.45}._section_1ac6r_11 h3{margin:32px 0 18px;font-size:22px;font-weight:550}._bench_1ac6r_16{border:1px solid var(--line);background:var(--panel);border-radius:9px;min-width:0;margin:28px 0;padding:24px}._pair_1ac6r_17{grid-template-columns:repeat(2,minmax(0,1fr));gap:26px;margin:24px 0;display:grid}._figure_1ac6r_18{border-left:2px solid var(--line);background:var(--panel);margin:0;padding:20px}._figure_1ac6r_18 figcaption{color:var(--muted);margin-top:15px;font-size:14px;line-height:1.8}._tokens_1ac6r_20{flex-wrap:wrap;align-items:center;gap:9px;min-height:46px;display:flex}._one_1ac6r_21,._two_1ac6r_21,._five_1ac6r_21{color:#14212a;border:1px solid #526473;border-radius:50%;flex:0 0 39px;justify-content:center;align-items:center;width:39px;height:39px;font-size:17px;font-weight:650;display:inline-flex}._one_1ac6r_21{background:#a7d6ed}._two_1ac6r_21{background:#edc779}._five_1ac6r_21{background:#e8b6ce}._empty_1ac6r_25{color:var(--muted);font-size:15px;line-height:1.8}._equation_1ac6r_26{border-left:2px solid var(--gold);background:var(--soft);max-width:100%;margin:23px 0;padding:15px 20px;font-size:16px;overflow-x:auto}._equation_1ac6r_26 .katex-display{margin:.35em 0}._equation_1ac6r_26 .katex-display>.katex{text-align:left}._derivation_1ac6r_29{border-left:2px solid var(--teal);margin:24px 0;padding:0 22px}._slider_1ac6r_30{gap:15px;max-width:480px;margin:5px 0 25px;font-size:16px;display:grid}._slider_1ac6r_30 input{width:100%;accent-color:var(--teal);cursor:pointer;min-height:28px}._controls_1ac6r_32{flex-wrap:wrap;align-items:center;gap:10px;margin:20px 0;display:flex}._controls_1ac6r_32 button,._button_1ac6r_33{background:var(--button);color:var(--ink);cursor:pointer;border:1px solid #657582;border-radius:5px;padding:10px 14px;font-size:14px}._controls_1ac6r_32 button:hover,._button_1ac6r_33:hover{border-color:var(--gold)}._controls_1ac6r_32 button:disabled{opacity:.45;cursor:default}:is(._lesson_1ac6r_1 button:focus-visible,._lesson_1ac6r_1 input:focus-visible,._lesson_1ac6r_1 summary:focus-visible,._lesson_1ac6r_1 a:focus-visible){outline:2px solid var(--gold);outline-offset:4px}._readout_1ac6r_37{color:var(--teal);overflow-wrap:anywhere;margin:18px 0;font-size:16px;line-height:1.9;display:block}._hint_1ac6r_38{color:var(--muted);font-size:14px!important}._tableWrap_1ac6r_39{max-width:100%;margin:24px 0;overflow-x:auto}._table_1ac6r_39{border-collapse:collapse;width:100%;font-size:14px}._table_1ac6r_39 caption{text-align:left;color:var(--muted);min-width:260px;margin-bottom:15px;line-height:1.8}._table_1ac6r_39 th,._table_1ac6r_39 td{border:1px solid var(--line);text-align:center;min-width:50px;padding:12px 10px;line-height:1.65}._table_1ac6r_39 th{color:var(--gold);background:var(--soft);font-weight:550}._table_1ac6r_39 td small{font-size:12px}._table_1ac6r_39 ._counted_1ac6r_45{background:var(--selection);color:var(--teal)}._table_1ac6r_39 ._match_1ac6r_46{background:var(--match)}._choiceList_1ac6r_47{margin:20px 0;padding-left:28px}._choiceList_1ac6r_47 li{border-bottom:1px solid var(--line);padding:15px 0 18px 5px;line-height:1.9}._choiceList_1ac6r_47 ._tokens_1ac6r_20{margin-top:9px}._tiling_1ac6r_50{gap:0;width:100%;max-width:720px;min-height:66px;margin:25px 0;display:flex}._shortTile_1ac6r_51,._longTile_1ac6r_51{color:#14212a;border:2px solid #425868;border-radius:4px;justify-content:center;align-items:center;min-width:0;font-size:20px;font-weight:650;display:flex}._shortTile_1ac6r_51{background:#a7d6ed}._longTile_1ac6r_51{background:#edc779}._lesson_1ac6r_1 details{border-top:1px solid var(--line);border-bottom:1px solid var(--line);margin:24px 0;padding:20px 0}._lesson_1ac6r_1 summary{cursor:pointer;color:var(--gold);font-size:16px;line-height:1.9}._answer_1ac6r_56{padding:8px 12px}@media (max-width:720px){._lesson_1ac6r_1{padding:22px 18px 72px}._lesson_1ac6r_1 p{font-size:15px;line-height:1.95}._bench_1ac6r_16{padding:18px 12px}._pair_1ac6r_17{grid-template-columns:1fr;gap:15px}._figure_1ac6r_18{padding:15px}._section_1ac6r_11{padding-top:35px}._section_1ac6r_11+._section_1ac6r_11{margin-top:30px}._equation_1ac6r_26{padding:14px 12px;font-size:14px}._table_1ac6r_39 th,._table_1ac6r_39 td{padding:10px 6px}._controls_1ac6r_32 button{flex:auto}._readout_1ac6r_37{font-size:15px}._derivation_1ac6r_29{padding-left:14px}._answer_1ac6r_56{padding-left:4px;padding-right:4px}}._weightStrip_1ac6r_73{flex-wrap:wrap;align-items:center;gap:2px;margin:15px 0;display:flex}._blueUnit_1ac6r_74,._goldUnit_1ac6r_74{color:#14212a;border:1px solid #526473;justify-content:center;align-items:center;width:40px;height:40px;display:flex}._blueUnit_1ac6r_74{background:#a7d6ed}._goldUnit_1ac6r_74{background:#edc779}._removal_1ac6r_77{border-top:1px solid var(--line);margin-top:20px;padding-top:1px}._removedTile_1ac6r_78{border:2px dashed var(--muted);color:var(--muted);justify-content:center;align-items:center;min-width:0;font-size:20px;display:flex}._controls_1ac6r_32 button[aria-pressed=true]{background:var(--selection);color:var(--teal);border-color:var(--teal)}._history_1ac6r_82{align-items:center;gap:10px;min-height:44px;display:flex}._recordList_1ac6r_83{margin:18px 0;padding:0;list-style:none}._recordList_1ac6r_83 li{border-top:1px solid var(--line);gap:8px;padding:15px 0;line-height:1.8;display:grid}._recordList_1ac6r_83 li span{color:var(--muted);font-size:14px}