.math-skill-page{--math-ink:#edf2ef;--math-muted:#b6c7c3;--math-green:#9cdbc0;--math-line:#35464c;--math-background:#101a22;--math-surface:#17252d;--math-surface-muted:#1c2f35;--math-surface-accent:#203c37;--math-surface-csec:#1b332d;--math-surface-identity:#21362f;--math-button-fill:#a8dec8;--math-button-ink:#0e3022;--math-button-hover:#c0ecd8;--math-open-line:#587b71;--math-csec-line:#667d58;--math-number-background:#22383b;--math-number-ink:#bad2c8;--math-badge-background:#334e3f;--math-post-background:#3d3830;--math-post-ink:#e5cda5;--math-worked-ink:#c5dccc;--math-warning:#e7c475;--math-link-background:#233d34;--math-link-hover:#2c5141;--math-link-ink:#aee6c4;--math-row-hover:#20343b;--lightningcss-light: ;--lightningcss-dark:initial;color-scheme:dark;background:var(--math-background);width:100%;max-width:none;min-height:100svh;color:var(--math-ink);margin:0;padding:0;font-size:15px;line-height:1.6}.math-skill-page[data-theme=light]{--lightningcss-light:initial;--lightningcss-dark: ;color-scheme:light;--math-ink:#203b36;--math-muted:#596b65;--math-green:#226d56;--math-line:#d9e3dc;--math-background:#f7f8f3;--math-surface:#fffefa;--math-surface-muted:#eff2e9;--math-surface-accent:#edf3e8;--math-surface-csec:#f0f5ea;--math-surface-identity:#e7eee1;--math-button-fill:#226d56;--math-button-ink:#fff;--math-button-hover:#185541;--math-open-line:#91b4a0;--math-csec-line:#a6b99a;--math-number-background:#f0f2eb;--math-number-ink:#577164;--math-badge-background:#dce8cf;--math-post-background:#eeece3;--math-post-ink:#746748;--math-worked-ink:#41574b;--math-warning:#927424;--math-link-background:#e5efe0;--math-link-hover:#d5e5cd;--math-link-ink:#226343;--math-row-hover:#eef2e85e}.math-skill-page *{box-sizing:border-box}.math-skill-page [hidden]{display:none!important}.math-skill-page a{text-decoration:none}.math-skill-page button,.math-skill-page summary,.math-skill-page select{cursor:pointer}.math-skill-page button{font:inherit}.math-skill-page :is(a,button,summary,input,select):focus-visible{outline-offset:4px;outline:3px solid #b3842b}.math-top-nav{color:#eaf2ec;background:#0c1a23;justify-content:space-between;align-items:center;gap:24px;padding:19px max(24px,50vw - 620px);display:flex}.math-top-nav a{color:inherit;align-items:center;gap:8px;font-size:13px;display:inline-flex}.math-top-nav .math-brand{letter-spacing:-.4px;gap:6px;font-size:17px}.math-brand>span{color:#a9dbc1;border:1px solid #91baa482;border-radius:8px;margin-right:7px;padding:7px}.math-page-body{max-width:1240px;margin:auto;padding:30px 24px 0}.math-skill-check{border:1px solid var(--math-line);background:var(--math-surface);border-radius:8px;margin:24px 0 0;padding:20px 22px}.math-skill-check-header{flex-wrap:wrap;justify-content:space-between;align-items:center;gap:18px 28px;display:flex}.math-skill-check-header>div:first-child{flex:360px}.math-skill-check h2{letter-spacing:-.4px;margin:0 0 6px;font-size:22px;line-height:1.25}.math-skill-check p{max-width:530px;color:var(--math-muted);margin:0;font-size:16px;line-height:1.5}.math-skill-check-actions{flex-wrap:wrap;align-items:center;gap:12px 18px;display:flex}.math-skill-check .math-button,.math-skill-check .math-text-button{font-size:14px}.math-skill-check .math-pdf-viewer{margin-top:20px}.math-breadcrumb{color:var(--math-muted);align-items:center;gap:12px;margin-bottom:28px;font-size:12px;display:flex}.math-breadcrumb a{color:var(--math-muted)}.math-hero-content{grid-template-columns:1.4fr 1fr;align-items:center;gap:40px;padding-bottom:36px;display:grid}.math-kicker{color:var(--math-green);letter-spacing:.14em;margin:0 0 10px;font-size:11px;font-weight:650}.math-hero h1{letter-spacing:-2px;margin:0;font-size:clamp(38px,4vw,54px);font-weight:600;line-height:1.08}.math-hero h1>span{letter-spacing:-1px;color:var(--math-green);margin-top:15px;font-family:Georgia,Times New Roman,serif;font-size:clamp(27px,2.8vw,38px);font-weight:400;line-height:1.17;display:block}.math-hero-description{color:var(--math-muted);max-width:500px;margin:18px 0 0;font-size:15px;line-height:1.75}.math-hero-art{text-align:center;padding:20px 0;font-family:Georgia,Times New Roman,serif}.math-art-top,.math-art-bottom{font-family:var(--font-geist-sans), sans-serif;color:var(--math-muted);letter-spacing:.13em;font-size:11px;display:block}.math-art-expression{letter-spacing:-.6px;margin:10px 0;font-size:clamp(24px,3vw,38px);display:block}.math-art-branches{width:50%;max-width:200px;height:45px;margin:auto;display:flex}.math-art-branches span{border-top:1px solid #7fa996;width:50%;height:100%}.math-art-branches span:first-child{border-left:1px solid #7fa996;border-top-left-radius:20px}.math-art-branches span:last-child{border-right:1px solid #7fa996;border-top-right-radius:20px}.math-hero-art>div{justify-content:center;gap:18px;margin:7px 0 18px;display:flex}.math-hero-art>div>span{background:var(--math-surface-identity);color:var(--math-green);border-radius:8px;padding:6px 14px;font-size:clamp(23px,2.5vw,31px)}.math-hero-footer{border-top:1px solid var(--math-line);border-bottom:1px solid var(--math-line);justify-content:space-between;align-items:center;gap:16px;padding:16px 0;font-size:12px;display:flex}.math-hero-footer>div{flex-wrap:wrap;align-items:center;gap:12px;display:flex}.math-hero-footer i{color:#8b9990;font-style:normal}.math-hero-footer a{color:var(--math-green);align-items:center;gap:8px;display:flex}.math-columns{grid-template-columns:minmax(0,1.85fr) minmax(0,1fr);align-items:start;gap:46px;padding:34px 0 48px;display:grid}.math-column-heading{justify-content:space-between;align-items:center;gap:15px;margin-bottom:12px;display:flex}.math-column-heading .math-kicker{margin-bottom:4px}.math-column-heading h2{letter-spacing:-.65px;margin:0;font-size:24px;font-weight:550;line-height:1.25}.math-reviewed{color:var(--math-green);background:var(--math-surface-muted);white-space:nowrap;border-radius:5px;padding:5px 9px;font-size:11px}.math-column-intro{color:var(--math-muted);margin:0 0 22px;font-size:13px;line-height:1.7}.math-prerequisites{background:var(--math-surface-muted);border:1px solid var(--math-line);border-radius:9px;margin-bottom:26px}.math-prerequisites>summary{align-items:center;gap:12px;padding:14px 18px;font-size:13px;font-weight:550;list-style:none;display:flex}.math-prerequisites>summary small{color:var(--math-muted);font-size:11px;font-weight:400;display:block}.math-prerequisites>summary>svg:last-child{margin-left:auto}.math-prerequisites>div{padding:0 18px 16px;font-size:13px}.math-prerequisites>div>p{margin:8px 0}.math-prerequisites ol{padding-left:20px}.math-prerequisites ol>li{padding:6px 0}.math-prerequisites ol summary{color:var(--math-green);font-size:12px}.math-prerequisites ol p{margin:7px 0}.math-stage-label{color:var(--math-muted);text-transform:uppercase;letter-spacing:.08em;justify-content:space-between;gap:12px;margin:16px 0 4px;padding:10px 0;font-size:10px;display:flex}.math-stage-label.is-csec{color:var(--math-green)}.math-stage-label>span:last-child{white-space:nowrap;letter-spacing:0;text-transform:none}.math-level{border:1px solid var(--math-line);background:var(--math-surface);border-radius:10px;margin-bottom:10px;scroll-margin-top:24px;overflow:hidden}.math-level.is-open{border-color:var(--math-open-line)}.math-level.is-csec{background:var(--math-surface-csec);border-color:var(--math-csec-line)}.math-level-title{flex:1;min-width:0;margin:0;font-weight:500}.math-level-button{text-align:left;width:100%;color:var(--math-ink);background:0 0;border:0;align-items:center;gap:16px;padding:18px;display:flex}.math-level-button:hover{background:var(--math-row-hover)}.math-level-button>svg:last-child{color:var(--math-muted);flex-shrink:0;margin-left:auto;transition:transform .15s}.math-level.is-open .math-level-button>svg:last-child{transform:rotate(180deg)}.math-level-number{background:var(--math-number-background);width:42px;height:47px;color:var(--math-number-ink);border-radius:6px;flex-shrink:0;place-items:center;font-family:Georgia,serif;font-size:20px;display:grid}.math-level.is-open 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17px 19px}.math-level-copy>span:nth-child(2){font-size:15px}}@media (max-width:760px){.math-columns{grid-template-columns:minmax(0,1fr);gap:40px}.math-exam-column{border-left:0;border-top:1px solid var(--math-line);padding:28px 0 0}.math-hero-content{gap:18px}.math-hero-art>div{gap:8px}.math-hero-art>div>span{padding:5px 8px}.math-hero-footer{align-items:start}.math-hero-footer>div{gap:8px}.math-hero-footer>a{flex-shrink:0}}@media (max-width:480px){.math-top-nav{gap:12px;padding:15px 16px}.math-top-nav .math-brand{flex-wrap:wrap;gap:4px;font-size:13px}.math-brand>span{display:none}.math-top-nav>a:last-child{white-space:nowrap;font-size:11px}.math-page-body{padding:23px 16px 0}.math-breadcrumb{margin-bottom:23px}.math-hero-content{grid-template-columns:1fr;padding-bottom:22px}.math-hero h1{font-size:42px}.math-hero h1>span{font-size:32px}.math-hero-description{font-size:13px}.math-hero-art{padding:8px 0 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(prefers-reduced-motion:reduce){.math-level-button>svg:last-child{transition:none}}.math-level-heading-row{align-items:center;display:flex}.math-mastered-button{color:var(--math-muted);border:1px solid var(--math-line);background:0 0;border-radius:5px;flex-shrink:0;align-items:center;gap:5px;margin-right:16px;padding:8px 10px;font-size:11px;display:inline-flex}.math-mastered-button:hover{border-color:var(--math-green);color:var(--math-green)}.math-mastered-button.is-mastered{background:var(--math-button-fill);border-color:var(--math-button-fill);color:var(--math-button-ink)}.math-mastered-button:not(.is-mastered) svg{opacity:.35}.math-pdf-actions{color:var(--math-muted);flex-wrap:wrap;justify-content:space-between;align-items:center;gap:8px;padding:12px 0 7px;font-size:10px;display:flex}.math-pdf-actions>div{gap:15px;display:flex}.math-pdf-viewer{border:1px solid var(--math-line);background:var(--math-number-background);border-radius:6px;width:100%;min-width:0;margin:0;padding:0;display:block;overflow:hidden}.math-pdf-toolbar{border-bottom:1px solid var(--math-line);color:var(--math-muted);flex-wrap:wrap;align-items:center;gap:8px;padding:10px 12px;font-size:11px;display:flex}.math-pdf-toolbar button,.math-pdf-toolbar select{border:1px solid var(--math-line);background:var(--math-surface);color:var(--math-green);border-radius:4px;padding:5px 7px;font-size:11px}.math-pdf-toolbar button:disabled{opacity:.45;cursor:default}.math-pdf-toolbar select{margin-left:auto}.math-pdf-pages{scrollbar-gutter:stable;min-height:380px;max-height:680px;position:relative;overflow:auto}.math-pdf-page{width:max-content;min-width:100%;padding:16px}.math-pdf-page canvas{display:block;box-shadow:0 2px 8px #233c3012}.math-pdf-page canvas[hidden]{display:none}.math-pdf-status{text-align:center;color:var(--math-muted);font-size:12px;position:absolute;inset:30px 15px auto}.math-answer-key{border:1px solid var(--math-line);background:var(--math-surface-accent);border-radius:6px;margin-top:18px;padding:12px 15px;font-size:12px}.math-answer-key summary{color:var(--math-green);cursor:pointer;font-weight:550}.math-answer-key>p{color:var(--math-muted);margin:12px 0}.math-answer-key ol{margin:0;padding-left:21px}.math-answer-key li{padding-left:5px}.math-answer-key li+li{margin-top:12px}.math-answer-key li p{margin:0}.math-answer-key li p+p{color:var(--math-muted);margin-top:3px;font-size:11px}@media (max-width:600px){.math-level-heading-row{flex-wrap:wrap}.math-level-title{flex-basis:100%}.math-mastered-button{margin:0 0 14px 18px}.math-pdf-pages{max-height:560px}}@media (max-width:480px){.math-mastered-button{margin-left:11px}}.math-nav-actions{align-items:center;gap:22px;display:flex}.math-theme-toggle{color:#eaf2ec;background:0 0;border:1px solid #91baa45e;border-radius:6px;align-items:center;gap:8px;padding:7px 10px;display:inline-flex;font-size:12px!important}.math-theme-track{background:#4a6065;border-radius:10px;width:27px;height:16px;padding:3px}.math-theme-track>span{background:#eaf2ec;border-radius:50%;width:10px;height:10px;display:block}.math-theme-toggle[aria-checked=true] .math-theme-track{background:#7ec3a2}.math-theme-toggle[aria-checked=true] .math-theme-track>span{background:#132b24;transform:translate(11px)}@media (max-width:600px){.math-top-nav{flex-wrap:wrap;gap:12px}.math-nav-actions{flex-wrap:wrap;gap:15px}}