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.2s;display:block}.course-nav-overview:hover,.course-nav-overview.is-active{color:var(--c-fg)}.course-nav-group+.course-nav-group{margin-top:1.5rem}.course-nav-module{color:var(--c-fg);align-items:center;gap:.5rem;margin-bottom:.5rem;font-size:12px;font-weight:600;display:flex}.course-nav-module-n{font-family:var(--font-geist-mono),ui-monospace,monospace;color:var(--c-subtle);font-size:10px;font-weight:400}.course-nav-lesson{border-radius:var(--r-sm);color:var(--c-muted);transition:color .15s var(--ease-out),background-color .15s var(--ease-out);align-items:flex-start;gap:.5rem;padding:.35rem .6rem;font-size:13px;line-height:1.45;display:flex}.course-nav-lesson:hover{color:var(--c-fg);background:var(--c-surface)}.course-nav-lesson.is-active{color:var(--c-accent);background:var(--c-accent-wash);font-weight:500}.course-nav-check{border:1px solid var(--c-border);width:1.05rem;height:1.05rem;font-family:var(--font-geist-mono),ui-monospace,monospace;color:var(--c-subtle);border-radius:999px;flex:none;justify-content:center;align-items:center;margin-top:.1rem;font-size:9px;display:inline-flex}.course-nav-lesson.is-done .course-nav-check{background:var(--c-accent);border-color:var(--c-accent);color:var(--c-accent-fg)}.course-nav-lesson.is-done .course-nav-title{color:var(--c-subtle)}.course-nav-trigger{z-index:40;border:1px solid var(--c-border);background:var(--c-bg);color:var(--c-fg);cursor:pointer;border-radius:999px;align-items:center;gap:.4rem;padding:.55rem .9rem;font-size:12px;display:inline-flex;position:fixed;bottom:1rem;right:1rem;box-shadow:0 6px 20px #0000001f}@media (min-width:1024px){.course-nav-trigger{display:none}}.course-drawer{z-index:60;position:fixed;inset:0}.course-drawer-scrim{-webkit-backdrop-filter:blur(2px);backdrop-filter:blur(2px);background:#00000073;position:absolute;inset:0}.course-drawer-panel{background:var(--c-bg);border-left:1px solid var(--c-border);width:min(21rem,88vw);padding:1.25rem 1.25rem 3rem;position:absolute;inset:0 0 0 auto;overflow-y:auto}.course-drawer-head{font-family:var(--font-geist-mono),ui-monospace,monospace;text-transform:uppercase;letter-spacing:.06em;color:var(--c-subtle);justify-content:space-between;align-items:center;margin-bottom:1rem;font-size:11px;display:flex}.course-drawer-head button{color:var(--c-subtle);cursor:pointer;font-size:20px;line-height:1}.course-search{z-index:70;position:fixed;inset:0}.course-search-scrim{-webkit-backdrop-filter:blur(2px);backdrop-filter:blur(2px);background:#00000073;position:absolute;inset:0}.course-search-panel{background:var(--c-bg);border:1px solid var(--c-border);border-radius:var(--r-lg);flex-direction:column;width:min(34rem,100vw - 2rem);max-height:70vh;margin:12vh auto 0;display:flex;position:relative;overflow:hidden;box-shadow:0 20px 60px #0003}.course-search-field{border-bottom:1px solid var(--c-border);color:var(--c-subtle);flex:none;align-items:center;gap:.65rem;padding:.9rem 1.1rem;display:flex}.course-search-field input{color:var(--c-fg);background:0 0;border:none;outline:none;flex:1;font-size:14px}.course-search-field input::placeholder{color:var(--c-subtle)}.course-search-field kbd{font-family:var(--font-geist-mono),ui-monospace,monospace;border:1px solid var(--c-border);border-radius:var(--r-sm);color:var(--c-subtle);padding:.15rem .4rem;font-size:10px}.course-search-results{padding:.5rem;overflow-y:auto}.course-search-empty{text-align:center;color:var(--c-subtle);padding:1.5rem 1rem;font-size:13px}.course-search-results ul{flex-direction:column;gap:.15rem;display:flex}.course-search-results a{border-radius:var(--r-md);transition:background-color .1s var(--ease-out);align-items:baseline;gap:.65rem;padding:.55rem .65rem;display:flex}.course-search-results a.is-active{background:var(--c-accent-wash)}.course-search-kind{width:3.4rem;font-family:var(--font-geist-mono),ui-monospace,monospace;text-transform:uppercase;letter-spacing:.05em;color:var(--c-subtle);flex:none;font-size:10px}.course-search-main{flex-direction:column;gap:.15rem;min-width:0;display:flex}.course-search-title{color:var(--c-fg);font-size:13.5px;line-height:1.4}.course-search-subtitle{color:var(--c-subtle);text-overflow:ellipsis;white-space:nowrap;font-size:12px;overflow:hidden}.lesson-grid{grid-template-columns:minmax(0,1fr);gap:3rem;display:grid}@media (min-width:1280px){.lesson-grid{grid-template-columns:minmax(0,44rem)var(--rail);justify-content:center}}.lesson-column{min-width:0;max-width:44rem}.lesson-rail{display:none}@media (min-width:1280px){.lesson-rail{display:block}}.lesson-head{border-bottom:1px 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hr+h2{border-top:none;margin-top:2rem;padding-top:0}.course-prose hr{opacity:.6;border-top-style:dashed;margin:2.5rem 0 0}.key-idea{border-radius:var(--r-lg);border:1px solid var(--c-border);background:var(--c-accent-soft);border-left:3px solid var(--c-accent);color:var(--c-fg);margin:1.75rem 0;padding:1.1rem 1.25rem;font-size:15px;line-height:1.7}.key-idea p:last-child{margin-bottom:0}.recap-card{--accent:var(--c-subtle);border:1px solid var(--c-border);border-radius:var(--r-lg);background:color-mix(in srgb,var(--c-surface)55%,transparent);margin:.75rem 0;padding:.9rem 1.1rem;font-size:14px;line-height:1.7}.recap-card+.recap-card{margin-top:-1px}.recap-card[data-accent=idea]{--accent:#6366f1}.recap-card[data-accent=warn]{--accent:#d97706}.recap-card[data-accent=task]{--accent:#059669}:root.dark .recap-card[data-accent=idea]{--accent:#a5b4fc}:root.dark .recap-card[data-accent=warn]{--accent:#fbbf24}:root.dark .recap-card[data-accent=task]{--accent:#6ee7b7}.recap-label{font-family:var(--font-geist-mono),ui-monospace,monospace;letter-spacing:.09em;text-transform:uppercase;color:var(--accent);align-items:center;gap:.45rem;margin-bottom:.45rem;font-size:10px;display:flex}.recap-label:before{content:"";background:var(--accent);border-radius:999px;width:.4rem;height:.4rem}.recap-body>:last-child{margin-bottom:0}.recap-body p,.recap-body ul,.recap-body ol{margin-bottom:.6rem}.recap-body ul{padding-left:1.1rem}.figure-placeholder{border:1px dashed var(--c-border);border-radius:var(--r-lg);background:repeating-linear-gradient(45deg,transparent,transparent 9px,color-mix(in srgb,var(--c-surface)60%,transparent)9px,color-mix(in srgb,var(--c-surface)60%,transparent)18px);text-align:center;margin:2rem 0;padding:1.5rem}.figure-placeholder-name{font-family:var(--font-geist-mono),ui-monospace,monospace;color:var(--c-fg);margin-bottom:.4rem;font-size:12px}.figure-placeholder-spec{color:var(--c-muted);max-width:34rem;margin:0 auto .6rem;font-size:13px;line-height:1.6}.figure-placeholder-hint{color:var(--c-subtle);font-size:11px}.figure-placeholder-hint code{font-family:var(--font-geist-mono),ui-monospace,monospace;font-size:.92em}.figure-caption{color:var(--c-subtle);text-align:center;margin-top:.6rem;font-size:12.5px;line-height:1.6}.topic-toc{max-height:calc(100vh - 9rem);padding-bottom:2rem;position:sticky;top:6.5rem;overflow-y:auto}.topic-toc-label{font-family:var(--font-geist-mono),ui-monospace,monospace;letter-spacing:.09em;text-transform:uppercase;color:var(--c-subtle);margin-bottom:.85rem;font-size:10px}.topic-toc ul{border-left:1px solid var(--c-border)}.topic-toc a{color:var(--c-subtle);border-left:1px solid #0000;gap:.5rem;margin-left:-1px;padding:.3rem 0 .3rem 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auto}.overview-back{font-family:var(--font-geist-mono),ui-monospace,monospace;color:var(--c-subtle);margin-bottom:2rem;font-size:12px;transition:color .2s;display:inline-block}.overview-back:hover{color:var(--c-fg)}.overview-banner{aspect-ratio:5/2;border:1px solid var(--c-border);border-radius:var(--r-lg);background:var(--c-surface);width:100%;margin-bottom:2rem;position:relative;overflow:hidden}.overview-eyebrow{font-family:var(--font-geist-mono),ui-monospace,monospace;letter-spacing:.09em;text-transform:uppercase;color:var(--c-subtle);font-size:11px}.overview-head h1{font-family:var(--font-inter),system-ui,sans-serif;letter-spacing:-.02em;color:var(--c-fg);margin-top:.9rem;font-size:clamp(2.1rem,6vw,3.2rem);line-height:1.08}.overview-sub{color:var(--c-muted);max-width:38rem;margin-top:1.1rem;font-size:15px;line-height:1.8}.overview-stats{border-top:1px solid var(--c-border);border-bottom:1px solid var(--c-border);grid-template-columns:repeat(4,minmax(0,1fr));gap:1rem;margin-top:2rem;padding:1.1rem 0;display:grid}.overview-stats dt{font-family:var(--font-geist-mono),ui-monospace,monospace;letter-spacing:.08em;text-transform:uppercase;color:var(--c-subtle);font-size:10px}.overview-stats dd{color:var(--c-fg);font-variant-numeric:tabular-nums;margin-top:.3rem;font-size:1.35rem}.progress-summary{border:1px solid var(--c-border);border-radius:var(--r-lg);background:color-mix(in srgb,var(--c-surface)55%,transparent);flex-wrap:wrap;align-items:center;gap:1rem 1.25rem;margin-top:2rem;padding:1.15rem 1.25rem;display:flex}.progress-ring{flex:none;width:52px;height:52px;position:relative}.progress-ring svg{transform:rotate(-90deg)}.progress-ring-track{fill:none;stroke:var(--c-border);stroke-width:4px}.progress-ring-fill{fill:none;stroke:var(--c-accent);stroke-width:4px;stroke-linecap:round;transition:stroke-dashoffset .5s}.progress-ring-pct{font-family:var(--font-geist-mono),ui-monospace,monospace;color:var(--c-fg);font-variant-numeric:tabular-nums;place-items:center;font-size:10px;display:grid;position:absolute;inset:0}.progress-copy{flex:12rem}.progress-count{color:var(--c-fg);font-size:14px}.progress-hint{color:var(--c-subtle);margin-top:.2rem;font-size:11.5px}.progress-actions{align-items:center;gap:.75rem;display:flex}.progress-cta{background:var(--c-fg);color:var(--c-bg);transition:opacity .16s var(--ease-out),transform .16s var(--ease-out);border-radius:9999px;padding:10px 20px;font-size:14px;font-weight:500;line-height:1.3;display:inline-block}.progress-cta:hover{opacity:.88}.progress-cta:active{transform:scale(.97)}.progress-reset{color:var(--c-subtle);cursor:pointer;font-size:12px;transition:color .2s}.progress-reset:hover{color:var(--c-fg)}.overview-outline{margin-top:3.5rem}.overview-outline>h2{font-family:var(--font-geist-mono),ui-monospace,monospace;letter-spacing:.09em;text-transform:uppercase;color:var(--c-subtle);margin-bottom:1.5rem;font-size:11px}.outline-module+.outline-module{margin-top:2.5rem}.outline-module-head{align-items:baseline;gap:.85rem;display:flex}.outline-module-n{font-family:var(--font-geist-mono),ui-monospace,monospace;color:var(--c-subtle);font-size:11px}.outline-module-head h3{color:var(--c-fg);font-size:15px;font-weight:600}.outline-module-head p{color:var(--c-subtle);margin-top:.15rem;font-size:13px}.outline-lessons{gap:.5rem;margin-top:.85rem;margin-left:1.7rem;display:grid}.outline-lesson{border:1px solid var(--c-border);border-radius:var(--r-lg);justify-content:space-between;align-items:flex-start;gap:1rem;padding:.85rem 1rem;transition:border-color .2s,background-color .2s;display:flex}.outline-lesson:hover{border-color:var(--c-subtle);background:color-mix(in srgb,var(--c-surface)50%,transparent)}.outline-lesson-main{min-width:0}.outline-lesson-title{color:var(--c-fg);font-size:14px;line-height:1.4}.outline-lesson-n{font-family:var(--font-geist-mono),ui-monospace,monospace;letter-spacing:.07em;text-transform:uppercase;color:var(--c-subtle);margin-bottom:.15rem;font-size:10px;display:block}.outline-lesson-topics{color:var(--c-subtle);margin-top:.35rem;font-size:12px;line-height:1.55}.outline-lesson-meta{text-align:right;font-family:var(--font-geist-mono),ui-monospace,monospace;color:var(--c-subtle);white-space:nowrap;flex:none;font-size:10px;line-height:1.6}.overview-foot{border-top:1px solid var(--c-border);margin-top:3.5rem;padding-top:1.75rem}.overview-foot p{color:var(--c-subtle);max-width:36rem;font-size:13.5px;line-height:1.75}.overview-foot-link{font-family:var(--font-geist-mono),ui-monospace,monospace;color:var(--c-subtle);margin-top:1rem;font-size:12px;transition:color .2s;display:inline-block}.overview-foot-link:hover{color:var(--c-fg)}