:root{--hue:357;--subject-hue:var(--hue);--background:oklch(0.975 0.004 var(--hue));--surface:oklch(0.998 0.003 var(--hue));--surface-muted:oklch(0.952 0.007 var(--hue));--border:oklch(0.9 0.011 var(--hue));--text:oklch(0.26 0.005 var(--hue));--text-muted:oklch(0.53 0.011 var(--hue));--text-inverse:#ffffff;--subject-primary:oklch(0.53 0.177 var(--subject-hue));--subject-primary-hover:oklch(0.445 0.149 var(--subject-hue));--subject-secondary:oklch(0.873 0.05 var(--subject-hue));--subject-tint:color-mix(in srgb,var(--subject-secondary) 36%,var(--surface));--action-primary:var(--subject-primary);--action-primary-hover:var(--subject-primary-hover);--focus-ring:oklch(0.53 0.15 var(--subject-hue));--success:#237a51;--success-surface:#e4f3eb;--warning:#9a6518;--warning-surface:#f7edd9;--danger:#b13c35;--danger-surface:#f8e5e3;--info:#3e638d;--info-surface:#e5edf6;--progress-track:oklch(0.925 0.007 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4}.math-point{fill:var(--subject-primary);stroke:var(--surface);stroke-width:4}.math-point-ring{fill:none;stroke:color-mix(in srgb,var(--subject-primary) 36%,transparent);stroke-width:1.5}.math-reveal-late{opacity:1}.math-visual:not(.is-intro-active) .math-reveal-late{opacity:0}.math-visual.is-intro-active .math-reveal-late{animation:math-reveal .5s ease-out 1.45s both}.math-point-pulse{transform-box:fill-box;transform-origin:center}.math-visual.is-intro-active .math-point-pulse{animation:math-point-pulse 3.4s ease-in-out 2.1s infinite}.math-particles{opacity:0}.math-visual.is-intro-active .math-particles{opacity:1;transition:opacity .6s ease 2s}.math-particle{fill:var(--subject-primary);filter:drop-shadow(0 0 4px color-mix(in srgb,var(--subject-primary) 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var(--border);border-radius:var(--radius-md);background:var(--surface);display:grid;grid-template-columns:auto minmax(0,1fr) auto;grid-gap:24px;gap:24px;align-items:center;box-shadow:var(--shadow-sm)}.start-number{color:color-mix(in srgb,var(--subject-primary) 22%,transparent);font-family:var(--font-mono);font-size:3rem;font-weight:700;font-feature-settings:"tnum";font-variant-numeric:tabular-nums}.start-copy{min-width:0}.continue-title{margin:10px 0 6px;font-size:1.3rem}.guest-start .muted{max-width:600px;margin-bottom:0}.path-list{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));grid-gap:12px;gap:12px}.path-item{position:relative;min-height:180px;padding:20px;border:1px solid var(--border);border-radius:var(--radius-md);background:var(--surface);transition:transform var(--duration) var(--ease),border-color var(--duration) var(--ease),box-shadow var(--duration) 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auto;align-items:center;grid-gap:20px;gap:20px}.practice-icon{width:44px;height:44px;display:grid;place-items:center;border-radius:var(--radius-sm);background:var(--subject-tint);color:var(--subject-primary)}.secondary-entry h2{margin-bottom:6px}.secondary-entry .muted{margin-bottom:0}.pill{display:inline-flex;align-items:center;min-height:24px;padding:0 10px;border-radius:var(--radius-pill);background:var(--subject-secondary);color:var(--subject-primary-hover);font-size:12px;font-weight:600}.surface-grid{display:grid;grid-template-columns:minmax(0,1.3fr) minmax(280px,.7fr);grid-gap:24px;gap:24px}.surface{border-top:1px solid var(--border);padding:24px 0}.surface-bordered{border:1px solid var(--border);border-radius:var(--radius-md);padding:24px;background:var(--surface)}.continue-panel{display:grid;grid-template-columns:minmax(0,1fr) auto;grid-gap:20px;gap:20px;align-items:center}.summary-grid{display:grid;grid-template-columns:1fr 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6px;display:block}.course-preview-note p{margin-bottom:0;color:var(--text-muted);font-size:14px}.chapter-list{display:grid;grid-gap:20px;gap:20px}.chapter{border-top:1px solid var(--border);padding-top:20px}.chapter-header{display:grid;grid-template-columns:auto minmax(0,1fr) auto;grid-gap:16px;gap:16px;align-items:start}.chapter-number{width:32px;height:32px;display:grid;place-items:center;border-radius:50%;background:var(--subject-tint);color:var(--subject-primary);font-size:14px;font-weight:700;font-feature-settings:"tnum";font-variant-numeric:tabular-nums}.chapter-meta,.chapter-target{color:var(--text-muted);font-size:13px}.chapter-meta{display:flex;align-items:center;gap:12px}.lesson-list{margin:16px 0 0 48px;border-left:1px solid var(--border)}.lesson-row{min-height:64px;padding:12px 14px 12px 18px;display:grid;grid-template-columns:auto minmax(0,1fr) auto;align-items:center;grid-gap:12px;gap:12px;border-bottom:1px solid var(--border)}.lesson-status{width:24px;height:24px;display:grid;place-items:center;border:1px solid var(--border);border-radius:50%;color:var(--text-muted);font-size:12px}.lesson-status.demo{border-color:var(--subject-primary);color:var(--subject-primary)}.lesson-status.unavailable{background:var(--surface-muted)}.lesson-name{font-weight:600}.lesson-sub{font-size:12px}.lesson-row.unavailable,.lesson-sub{color:var(--text-muted)}.lesson-link{justify-self:end}.course-layout{display:grid;grid-template-columns:minmax(0,1fr) 260px;grid-gap:40px;gap:40px;padding-top:36px}.course-aside{align-self:start;position:-webkit-sticky;position:sticky;top:20px}.aside-title{margin-bottom:16px;font-weight:700}.milestone{padding:16px 0;border-top:1px solid var(--border)}.milestone strong{font-weight:600}.lesson-page{max-width:1380px;margin:0 auto;padding:20px 24px 72px}.lesson-toolbar{min-height:52px;display:flex;align-items:center;gap:14px;border-bottom:1px solid var(--border)}.toolbar-back{min-height:40px;padding-inline:0;color:var(--subject-primary);font-size:14px;font-weight:600}.toolbar-divider{height:20px;width:1px;background:var(--border)}.toolbar-title{min-width:0;overflow-wrap:anywhere;font-weight:600}.toolbar-step{margin-left:auto;color:var(--text-muted);font-size:13px;font-feature-settings:"tnum";font-variant-numeric:tabular-nums}.lesson-layout{display:grid;grid-template-columns:minmax(0,1fr) minmax(360px,.82fr);grid-gap:48px;gap:48px;padding-top:40px}.lesson-content{max-width:760px}.lesson-content-body{min-height:470px}.lesson-content h1{font-size:clamp(1.8rem,3.4vw,2.6rem)}.step-kicker{margin-bottom:10px;color:var(--subject-primary);font-size:13px;font-weight:600}.lesson-content p{color:var(--text-muted);font-size:1.02rem}.formula{margin:28px 0;padding:24px;border-left:3px solid var(--subject-primary);border-radius:var(--radius-md);background:var(--surface-muted);font-family:var(--font-serif);font-size:clamp(1.6rem,3.6vw,2.4rem);text-align:center}.example{margin-top:28px;padding-top:24px;border-top:1px solid var(--border)}.lesson-controls{align-self:start;position:-webkit-sticky;position:sticky;top:20px}.tool-panel{border:1px solid var(--border);border-radius:var(--radius-md);background:var(--surface);box-shadow:var(--shadow-sm);overflow:hidden}.tool-panel-header{padding:14px 18px;border-bottom:1px solid var(--border);display:flex;justify-content:space-between;align-items:center;gap:12px}.tool-panel-header strong{font-weight:600}.tool-panel-body{padding:18px}.chart-frame{aspect-ratio:1.35;width:100%;background:var(--surface-muted);border:1px solid var(--border);border-radius:var(--radius-sm)}.chart-frame svg{width:100%;height:100%;display:block}.range-row{display:flex;align-items:center;gap:12px;margin-top:16px;font-size:14px}.range-row 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var(--ease)}.option.selected,.option:hover{border-color:var(--subject-primary);background:var(--subject-tint)}.option.correct{border-color:var(--success);background:var(--success-surface)}.option.incorrect{border-color:var(--danger);background:var(--danger-surface)}.option-result{color:inherit;font-size:12px;font-weight:600;white-space:nowrap}.question-submit{margin-top:14px}.step-nav{justify-content:space-between;align-items:center;margin-top:24px}.step-nav,.step-nav-group{display:flex;gap:10px;flex-wrap:wrap}.step-nav-group{margin-left:auto}.completion{margin-top:20px;padding:24px;border:1px solid var(--subject-primary);border-radius:var(--radius-md);background:var(--subject-tint)}.completion h3{margin-top:14px}.summary-note{min-height:180px;display:flex;flex-direction:column;justify-content:center;align-items:flex-start;gap:14px}.summary-note p{margin:0}.tool-hint{margin:14px 0 0;color:var(--text-muted);font-size:14px}.lesson-local-error{max-width:720px;min-height:560px;display:flex;flex-direction:column;justify-content:center;align-items:flex-start}.lesson-local-error>svg{margin-bottom:18px;color:var(--danger)}.practice-header{padding:52px 0 32px;border-bottom:1px solid var(--border)}.practice-controls{display:flex;flex-wrap:wrap;gap:16px;margin-top:24px}.practice-controls .form-field{min-width:190px}.select-control{min-height:40px;border:1px solid var(--border);border-radius:var(--radius-sm);padding:0 12px;background:var(--surface);color:var(--text);font-size:14px}.practice-shell{max-width:800px;margin:0 auto;padding-top:36px}.empty-state{max-width:680px;min-height:420px;display:flex;flex-direction:column;align-items:flex-start;justify-content:center}.practice-question{border-top:1px solid var(--border);padding-top:24px;margin-top:24px}.question-title{margin-top:14px}.number-input{width:100%;min-height:44px;margin-top:12px;border:1px solid var(--border);border-radius:var(--radius-sm);padding:0 14px;background:var(--surface);color:var(--text);font-size:15px}.number-input:focus,.select-control:focus{border-color:var(--subject-primary)}.progress,.progress-row{width:100%;display:flex;align-items:center;gap:12px}.progress-track{height:6px;flex:1 1;overflow:hidden;border-radius:var(--radius-pill);background:var(--progress-track)}.progress-value{width:var(--progress-percent,0);height:100%;display:block;border-radius:inherit;background:var(--progress-value);transition:width .2s var(--ease)}.progress-label{min-width:max-content;color:var(--text-muted);font-size:13px;font-feature-settings:"tnum";font-variant-numeric:tabular-nums}.status-badge{width:-moz-fit-content;width:fit-content;min-height:24px;padding:2px 10px;border-radius:var(--radius-pill);display:inline-flex;align-items:center;gap:6px;background:var(--surface-muted);color:var(--text-muted);font-size:12px;font-weight:600}.status-badge-info{background:var(--info-surface);color:var(--info)}.status-badge-success{background:var(--success-surface);color:var(--success)}.status-badge-warning{background:var(--warning-surface);color:var(--warning)}.status-badge-danger{background:var(--danger-surface);color:var(--danger)}.feedback{margin-top:16px;padding:14px 16px;border:1px solid color-mix(in srgb,var(--info) 30%,var(--surface));border-radius:var(--radius-md);display:grid;grid-template-columns:auto minmax(0,1fr);grid-gap:10px;gap:10px;background:var(--info-surface)}.feedback-success,.feedback.correct-feedback{border-color:color-mix(in srgb,var(--success) 30%,var(--surface));background:var(--success-surface)}.feedback-error,.feedback.error-feedback{border-color:color-mix(in srgb,var(--danger) 30%,var(--surface));background:var(--danger-surface)}.feedback strong{display:block;margin-bottom:3px}.form-field{min-width:0;display:grid;grid-gap:6px;gap:6px}.form-label{color:var(--text-muted);font-weight:600}.form-error,.form-hint,.form-label{font-size:13px}.form-hint{color:var(--text-muted)}.form-error{color:var(--danger)}.state-view{max-width:680px;min-height:430px;display:flex;flex-direction:column;align-items:flex-start;justify-content:center}.state-view-icon{margin-bottom:20px;color:var(--subject-primary)}.state-view h1{max-width:640px;margin-bottom:14px;font-size:clamp(1.8rem,3.4vw,2.6rem)}.state-view-description{max-width:580px;color:var(--text-muted);font-size:1.02rem}.state-view-action{margin-top:16px;display:flex;flex-wrap:wrap;gap:10px}.loading-state{min-height:430px;padding:80px 0;display:flex;flex-direction:column;justify-content:center}.skeleton{border-radius:var(--radius-sm);background:linear-gradient(90deg,var(--surface-muted) 25%,var(--surface) 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var(--border)}.settings-group-header{display:flex;align-items:center;gap:8px;margin-bottom:10px}.settings-group-title{margin:0;padding-left:8px;border-left:3px solid var(--subject-primary);font-size:13px;font-weight:700;letter-spacing:.04em}.settings-value-badge{min-width:36px;padding:1px 8px;border-radius:var(--radius-pill);background:var(--surface-muted);color:var(--text-muted);font-size:12px;font-feature-settings:"tnum";font-variant-numeric:tabular-nums;text-align:center}.settings-reset{width:26px;height:26px;margin-left:auto;display:inline-grid;place-items:center;border:1px solid var(--border);border-radius:var(--radius-sm);background:var(--surface);color:var(--text-muted);transition:opacity var(--duration) var(--ease),color var(--duration) var(--ease),border-color var(--duration) var(--ease)}.settings-reset:hover{border-color:var(--subject-primary);color:var(--subject-primary)}.settings-reset[disabled]{opacity:0;pointer-events:none}.theme-mode-group{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));grid-gap:8px;gap:8px}.theme-mode-button{min-height:52px;display:inline-flex;flex-direction:column;align-items:center;justify-content:center;gap:4px;border:1px solid var(--border);border-radius:var(--radius-sm);background:var(--surface);color:var(--text-muted);font-size:12px;font-weight:600;transition:border-color var(--duration) var(--ease),color var(--duration) var(--ease),background var(--duration) var(--ease)}.theme-mode-button:hover,.theme-mode-button[aria-pressed=true]{border-color:var(--subject-primary);color:var(--subject-primary)}.theme-mode-button[aria-pressed=true]{background:var(--subject-tint)}.hue-slider{-webkit-appearance:none;-moz-appearance:none;appearance:none;width:100%;min-height:40px;margin:0;background:transparent;cursor:pointer}.hue-slider::-webkit-slider-runnable-track{height:12px;border:1px solid color-mix(in srgb,var(--border) 70%,transparent);border-radius:var(--radius-pill);background:linear-gradient(90deg,hsl(0 72% 55%),hsl(60 72% 55%),hsl(120 72% 55%),hsl(180 72% 55%),hsl(240 72% 55%),hsl(300 72% 55%),hsl(360 72% 55%))}.hue-slider::-webkit-slider-thumb{-webkit-appearance:none;margin-top:-5px;width:20px;height:20px;border:2px solid var(--surface);border-radius:50%;background:oklch(.62 .19 var(--hue));box-shadow:0 1px 5px rgb(0 0 0/.35)}.hue-slider::-moz-range-track{height:12px;border:1px solid color-mix(in srgb,var(--border) 70%,transparent);border-radius:var(--radius-pill);background:linear-gradient(90deg,hsl(0 72% 55%),hsl(60 72% 55%),hsl(120 72% 55%),hsl(180 72% 55%),hsl(240 72% 55%),hsl(300 72% 55%),hsl(360 72% 55%))}.hue-slider::-moz-range-thumb{width:16px;height:16px;border:2px solid var(--surface);border-radius:50%;background:oklch(.62 .19 var(--hue));box-shadow:0 1px 5px rgb(0 0 0/.35)}@media (max-width:900px){.nav-links{display:none}.menu-toggle{display:grid}.course-header-grid,.course-layout,.home-hero,.lesson-layout,.surface-grid{grid-template-columns:1fr}.home-hero{min-height:auto;gap:44px;padding-top:56px}.path-list{grid-template-columns:repeat(3,minmax(0,1fr))}.course-aside,.lesson-controls{position:static}}@media (max-width:640px){.site-header{width:100%;padding-inline:0}.nav-shell{min-height:60px;padding:0 16px}.brand{padding:0 8px}.header-end{justify-self:end}.nav-links{display:none}.menu-toggle{display:grid}.account-slot span{display:none}.page-shell{padding:88px 16px 56px}.section{padding-top:48px}.home-hero{gap:28px;padding:36px 0 32px}.hero-copy h1{margin-bottom:20px;font-size:clamp(2.4rem,11vw,3.2rem)}.hero-copy>p:not(.eyebrow){margin-bottom:26px;font-size:1.02rem}.hero-actions{gap:12px}.math-stage{min-height:290px}.math-stage .chart-frame{inset:-8px -24px -12px}.hero-atmosphere{inset:160px -20px 0}.hero-field-rays{opacity:.18}.hero-field-orbit-wide{opacity:.5}.section-note{width:100%}.continue-panel,.guest-start{grid-template-columns:1fr}.guest-start{gap:16px;padding:20px}.start-number{display:none}.guest-start .button{justify-self:start}.path-list{grid-template-columns:1fr 1fr}.path-item{min-height:164px;padding:16px}.path-index{margin-bottom:20px}.summary-grid{grid-template-columns:1fr 1fr}.secondary-entry{grid-template-columns:auto minmax(0,1fr);padding:20px}.secondary-entry .button{grid-column:1/-1;justify-self:start}.course-header{padding-top:40px}.course-layout{gap:24px}.chapter-header{grid-template-columns:auto minmax(0,1fr)}.chapter-meta{grid-column:2}.chapter-toggle{grid-row:1/span 2;grid-column:3}.lesson-list{margin-left:0}.lesson-row{grid-template-columns:auto minmax(0,1fr);padding-left:12px}.lesson-row .lesson-sub+span,.lesson-row .text-link{grid-column:2}.lesson-page{padding:12px 16px 52px}.lesson-toolbar{flex-wrap:wrap;min-height:72px;padding-bottom:12px}.toolbar-step{margin-left:0;width:100%}.lesson-layout{padding-top:28px;gap:28px}.tool-panel-header{padding:12px 14px}}@media (prefers-reduced-motion:reduce){*,:after,:before{scroll-behavior:auto!important;transition-duration:.01ms!important;animation-duration:.01ms!important}.math-visual .math-draw-in{stroke-dashoffset:0}.math-visual .math-reveal-late{opacity:1}.math-visual .math-particles{display:none}.math-visual .math-point-pulse{transform:none}.hero-field-particles{display:none}.hero-field-ray{stroke-dashoffset:0}.hero-field-orbit{transform:none}}.editorial-shell{padding-top:112px}.editorial-hero{min-height:360px;padding:34px 0 56px;border-bottom:1px solid var(--border);display:grid;grid-template-columns:minmax(0,1fr) 380px;align-items:center;grid-gap:48px;gap:48px}.editorial-hero h1{margin-bottom:22px;font-size:clamp(2.7rem,6vw,4.8rem);line-height:1.04}.editorial-hero h1 em{color:var(--subject-primary);font-style:normal}.editorial-lead{max-width:580px;margin:0;color:var(--text-muted);font-size:1.08rem;line-height:1.75}.editorial-hero-mark{position:relative;min-height:240px;border:1px solid var(--border);border-radius:var(--radius-md);overflow:hidden;background:var(--surface-muted)}.editorial-hero-mark:after,.editorial-hero-mark:before{content:"";position:absolute;inset:24px;border:1px solid color-mix(in srgb,var(--subject-primary) 20%,transparent);border-radius:50%;transform:rotate(-22deg)}.editorial-hero-mark:after{inset:48px 34px;transform:rotate(34deg);border-color:color-mix(in srgb,var(--chart-secondary) 24%,transparent)}.hero-mark-line{position:absolute;left:12%;right:12%;height:1px;background:var(--border);transform:rotate(-17deg)}.hero-mark-line-one{top:51%}.hero-mark-line-two{top:52%;transform:rotate(24deg);background:color-mix(in srgb,var(--subject-primary) 48%,var(--border))}.hero-mark-dot{position:absolute;top:43%;left:49%;width:16px;height:16px;border:4px solid var(--surface);border-radius:50%;background:var(--subject-primary);box-shadow:0 0 0 8px color-mix(in srgb,var(--subject-primary) 15%,transparent)}.hero-mark-label{position:absolute;right:24px;bottom:18px;color:var(--subject-primary);font-family:var(--font-serif);font-size:20px;font-style:italic}.featured-article{margin-top:48px;padding:24px;border:1px solid var(--border);border-radius:var(--radius-md);display:grid;grid-template-columns:minmax(280px,.85fr) minmax(0,1.15fr);grid-gap:40px;gap:40px;align-items:center;background:var(--surface);box-shadow:var(--shadow-sm)}.featured-copy{padding:12px 12px 12px 0}.featured-copy h2{max-width:560px;margin-bottom:14px;font-size:clamp(1.6rem,3vw,2.35rem)}.article-row h3 a:hover,.featured-copy h2 a:hover{color:var(--subject-primary)}.featured-copy>.muted{max-width:560px;margin-bottom:20px;font-size:1rem}.article-meta{display:flex;flex-wrap:wrap;gap:12px;align-items:center;color:var(--text-muted);font-size:12px}.article-meta span+span:before{content:"•";margin-right:12px;color:var(--border)}.article-meta svg{vertical-align:-3px}.featured-copy .text-link{margin-top:22px}.article-art{position:relative;min-height:260px;overflow:hidden;border-radius:var(--radius-sm);display:grid;place-items:center;isolation:isolate}.article-art:after,.article-art:before{content:"";position:absolute;border:1px solid;border-radius:50%;opacity:.36}.article-art:before{width:190px;height:190px;transform:rotate(25deg)}.article-art:after{width:120px;height:220px;transform:rotate(-50deg)}.article-art span{position:relative;z-index:1;color:currentColor;font-family:var(--font-serif);font-size:76px;font-style:italic}.article-art i{position:absolute;width:13px;height:13px;border:3px solid;border-radius:50%;background:inherit;box-shadow:0 0 0 7px color-mix(in srgb,currentColor 15%,transparent)}.article-art-coral{color:#9d3d4d;background:#f8dfdc}.article-art-gold{color:#916018;background:#f4e6c7}.article-art-mint{color:#2c7564;background:#dcefe8}.article-art-sky{color:#3f658c;background:#dde9f4}.article-art-small{width:152px;min-height:118px}.article-art-small span{font-size:34px;font-family:var(--font-sans);font-style:normal;font-weight:700}.article-art-small:before{width:82px;height:82px}.article-art-small:after{width:52px;height:100px}.article-art-small i{width:8px;height:8px;border-width:2px;box-shadow:0 0 0 4px color-mix(in srgb,currentColor 15%,transparent)}.blog-library{padding-top:72px}.blog-heading{align-items:center;margin-bottom:20px}.blog-heading h2{margin-bottom:0}.blog-search,.community-search{min-height:42px;border:1px solid var(--border);border-radius:var(--radius-sm);display:inline-flex;align-items:center;gap:9px;padding:0 12px;background:var(--surface);color:var(--text-muted)}.blog-search input,.community-search input{width:200px;min-width:0;border:0;outline:0;background:transparent;color:var(--text);font-size:14px}.category-tabs{display:flex;flex-wrap:wrap;gap:8px;margin-bottom:10px;border-bottom:1px solid var(--border)}.category-tabs button,.sort-tabs button{min-height:40px;padding:0 12px;border:0;border-bottom:2px solid transparent;background:transparent;color:var(--text-muted);font-size:13px;font-weight:600}.category-tabs button.is-active,.category-tabs button:hover,.sort-tabs button.is-active,.sort-tabs button:hover{color:var(--subject-primary);border-color:var(--subject-primary)}.article-list{border-top:1px solid var(--border)}.article-row{min-height:164px;padding:22px 0;border-bottom:1px solid var(--border);display:grid;grid-template-columns:152px minmax(0,1fr) auto;align-items:center;grid-gap:24px;gap:24px}.article-row-copy{min-width:0}.article-row h3{margin:7px 0 5px;font-size:1.18rem}.article-row p{max-width:680px;margin:0 0 12px;font-size:14px}.article-tags{display:flex;flex-wrap:wrap;gap:8px;color:var(--subject-primary);font-size:12px;font-weight:600}.article-tags span+span{color:var(--text-muted)}.article-arrow{margin-left:auto}.empty-inline{padding:40px 0;color:var(--text-muted)}.newsletter-strip{margin-top:72px;padding:24px;border-top:1px solid var(--border);border-bottom:1px solid var(--border);display:grid;grid-template-columns:auto minmax(0,1fr) auto;align-items:center;grid-gap:20px;gap:20px}.newsletter-icon{width:44px;height:44px;display:grid;place-items:center;border-radius:var(--radius-sm);background:var(--subject-tint);color:var(--subject-primary)}.newsletter-strip h2{margin-bottom:4px}.newsletter-strip p{margin-bottom:0}.newsletter-form{display:flex;gap:8px}.newsletter-form input{width:210px;min-height:40px;padding:0 12px;border:1px solid var(--border);border-radius:var(--radius-sm);background:var(--surface);color:var(--text)}.newsletter-success{color:var(--success);font-weight:600;display:inline-flex;align-items:center;gap:7px}.article-page{max-width:920px;padding-top:112px}.back-link{display:inline-flex;align-items:center;gap:7px;min-height:40px;color:var(--subject-primary);font-size:14px;font-weight:600}.article-page-header{padding:32px 0 40px;border-bottom:1px solid var(--border);display:grid;grid-template-columns:240px minmax(0,1fr);align-items:center;grid-gap:36px;gap:36px}.article-art-large{min-height:220px}.article-page-header h1{margin-bottom:16px;font-size:clamp(2rem,5vw,3.55rem)}.article-page-lead{margin-bottom:20px;color:var(--text-muted);font-size:1.08rem}.article-body{max-width:700px;margin:0 auto;padding:54px 0 20px}.article-body>p{margin-bottom:28px;color:var(--text);font-size:1.08rem;line-height:1.9}.article-aside-note{margin-top:48px;padding:20px;border-left:3px solid var(--subject-primary);border-radius:var(--radius-sm);background:var(--subject-tint)}.article-aside-note span{display:block;margin-bottom:5px;color:var(--subject-primary);font-size:12px;font-weight:700;text-transform:uppercase}.article-aside-note strong{display:block;margin-bottom:10px}.article-aside-note .text-link{min-height:32px}.article-next{margin-top:40px;padding:24px 0;border-top:1px solid var(--border);display:grid;grid-gap:8px;gap:8px}.article-next>span{color:var(--text-muted);font-size:12px;text-transform:uppercase;letter-spacing:.08em}.article-next a{display:flex;justify-content:space-between;align-items:center;gap:16px;color:var(--subject-primary)}.community-shell{max-width:1440px;margin:0 auto;padding:96px 24px 72px;display:grid;grid-template-columns:220px minmax(0,680px) 280px;grid-gap:34px;gap:34px;align-items:start}.community-sidebar{position:-webkit-sticky;position:sticky;top:90px;min-width:0}.community-sidebar-head{display:flex;align-items:center;gap:10px;margin-bottom:20px}.community-logo{width:36px;height:36px;display:grid;place-items:center;border-radius:10px;background:var(--subject-primary);color:var(--text-inverse)}.community-sidebar-head span,.community-sidebar-head strong{display:block}.community-sidebar-head strong{font-size:15px}.community-sidebar-head span{color:var(--text-muted);font-size:12px}.community-compose-button{width:100%;min-height:42px;margin-bottom:26px;border:0;border-radius:var(--radius-sm);display:inline-flex;align-items:center;justify-content:center;gap:8px;background:var(--subject-primary);color:var(--text-inverse);font-weight:700}.community-compose-button:hover{background:var(--subject-primary-hover)}.community-nav-label{margin:0 10px 8px;color:var(--text-muted);font-size:11px;font-weight:700;letter-spacing:.08em;text-transform:uppercase}.community-nav button{width:100%;min-height:40px;padding:0 10px;border:0;border-radius:var(--radius-sm);display:flex;align-items:center;justify-content:space-between;background:transparent;color:var(--text-muted);font-size:14px;text-align:left}.community-nav button.is-active,.community-nav button:hover{background:var(--subject-tint);color:var(--subject-primary)}.community-nav button small{font-size:11px;color:inherit;opacity:.75}.community-sidebar-note{margin-top:48px;padding:14px;border:1px solid var(--border);border-radius:var(--radius-md);display:flex;gap:9px;background:var(--surface);color:var(--subject-primary)}.community-sidebar-note p{margin:0;color:var(--text-muted);font-size:12px;line-height:1.5}.community-sidebar-note strong{color:var(--text)}.community-feed{min-width:0}.community-feed-header{padding-bottom:22px;border-bottom:1px solid var(--border);display:flex;justify-content:space-between;gap:16px}.community-feed-header h1{margin-bottom:5px}.community-feed-header p{margin-bottom:0}.community-header-actions{display:flex;gap:8px}.community-toolbar{min-height:70px;display:flex;justify-content:space-between;align-items:center;gap:16px}.community-search{flex:1 1}.community-search input{width:100%}.sort-tabs{display:flex;align-items:center;gap:2px}.sort-tabs button{min-height:36px}.community-composer,.community-prompt{margin-bottom:16px;padding:16px;border:1px solid var(--border);border-radius:var(--radius-md);display:flex;align-items:flex-start;gap:12px;background:var(--surface);box-shadow:var(--shadow-sm)}.community-prompt{width:100%;align-items:center;color:var(--text-muted);text-align:left}.community-prompt span{flex:1 1}.community-prompt>svg{color:var(--subject-primary)}.composer-main{min-width:0;flex:1 1}.composer-main textarea{width:100%;min-height:80px;resize:vertical;border:0;outline:0;background:transparent;color:var(--text);line-height:1.6}.composer-actions{padding-top:10px;border-top:1px solid var(--border);display:flex;justify-content:space-between;align-items:center;gap:12px}.composer-actions>div{display:flex;gap:8px}.avatar{width:38px;height:38px;flex:0 0 auto;border-radius:50%;display:grid;place-items:center;font-weight:700}.avatar-self{background:var(--subject-tint);color:var(--subject-primary)}.avatar-member-0,.avatar-post-0{background:#f4d8d7;color:#9d3d4d}.avatar-member-1,.avatar-post-1{background:#d9ece5;color:#2c7564}.avatar-member-2,.avatar-post-2{background:#e8e0f2;color:#69508b}.avatar-post-3{background:#e5edf6;color:#3f658c}.community-post-list{border-top:1px solid var(--border)}.community-post{padding:22px 0;border-bottom:1px solid var(--border);display:flex;gap:12px}.community-post.is-featured{margin-inline:-14px;padding-inline:14px;border:1px solid color-mix(in srgb,var(--subject-primary) 34%,var(--border));border-radius:var(--radius-md);background:color-mix(in srgb,var(--subject-tint) 32%,var(--surface))}.post-main{min-width:0;flex:1 1}.post-header{min-height:26px;display:flex;justify-content:space-between;align-items:flex-start;gap:12px}.post-header>div{display:flex;flex-wrap:wrap;align-items:baseline;gap:7px}.post-header strong{font-size:14px}.post-header span{color:var(--text-muted);font-size:12px}.icon-button-quiet{width:30px;height:30px;border-color:transparent;background:transparent}.post-channel{width:-moz-fit-content;width:fit-content;margin-top:4px;color:var(--subject-primary);font-size:11px;font-weight:700}.community-post h2{margin:8px 0 5px;font-size:1.05rem}.community-post p{margin-bottom:16px;color:var(--text-muted);font-size:14px;line-height:1.7}.post-actions{display:flex;align-items:center;gap:22px;color:var(--text-muted)}.post-actions button{min-height:28px;padding:0;border:0;display:inline-flex;align-items:center;gap:6px;background:transparent;color:inherit;font-size:12px}.post-actions button.is-liked,.post-actions button:hover{color:var(--danger)}.post-actions button:last-child{margin-left:auto}.community-empty{padding:64px 24px;border-bottom:1px solid var(--border);display:flex;flex-direction:column;align-items:center;color:var(--text-muted);text-align:center}.community-empty svg{color:var(--subject-primary)}.community-empty h2{margin:14px 0 5px;color:var(--text);font-size:1.15rem}.community-empty p{margin-bottom:16px}.community-rightbar{position:-webkit-sticky;position:sticky;top:90px;min-width:0}.community-widget{padding:18px 0;border-top:1px solid var(--border)}.community-widget:first-child{padding-top:0;border-top:0}.widget-heading{display:flex;justify-content:space-between;align-items:center;gap:12px;margin-bottom:14px}.community-guidelines h2,.widget-heading h2{margin:0;font-size:1rem}.topic-card{padding:16px;border:1px solid var(--border);border-radius:var(--radius-md);background:var(--surface)}.topic-number{display:block;margin-bottom:12px;color:var(--subject-primary);font-family:var(--font-mono);font-size:12px}.topic-card strong{display:block;margin-bottom:5px}.topic-card p,.topic-meta{display:block;margin-bottom:12px;color:var(--text-muted);font-size:12px;line-height:1.55}.topic-meta{margin:0;font-size:11px}.community-widget>.text-link{min-height:34px;margin-top:8px;font-size:12px}.member-list{display:grid;grid-gap:15px;gap:15px}.member-row{display:grid;grid-template-columns:auto minmax(0,1fr) auto;align-items:center;grid-gap:9px;gap:9px}.avatar-member{width:30px;height:30px;font-size:12px}.member-row span,.member-row strong{display:block}.member-row strong{font-size:13px}.member-row span{color:var(--text-muted);font-size:11px}.member-row small{color:var(--subject-primary);font-family:var(--font-mono);font-size:10px}.community-guidelines ul{margin:12px 0 0;padding-left:17px;color:var(--text-muted);font-size:12px;line-height:2}@media (max-width:1100px){.community-shell{grid-template-columns:190px minmax(0,1fr);gap:28px}.community-rightbar{display:none}}@media (max-width:900px){.editorial-hero{grid-template-columns:minmax(0,1fr) 280px;gap:24px}.featured-article{grid-template-columns:minmax(220px,.8fr) minmax(0,1.2fr);gap:24px}.newsletter-strip{grid-template-columns:auto minmax(0,1fr)}.newsletter-form,.newsletter-success{grid-column:2}.community-shell{padding-top:88px}}@media (max-width:640px){.editorial-shell{padding-top:88px}.editorial-hero{min-height:0;padding:20px 0 36px;grid-template-columns:1fr}.editorial-hero-mark{min-height:160px}.featured-article{margin-top:28px;padding:16px;grid-template-columns:1fr;gap:22px}.featured-copy{padding:0}.featured-copy h2{font-size:1.65rem}.article-art{min-height:190px}.blog-library{padding-top:48px}.blog-heading{align-items:flex-start}.blog-search,.blog-search input{width:100%}.category-tabs{overflow-x:auto;flex-wrap:nowrap}.category-tabs button{white-space:nowrap}.article-row{grid-template-columns:88px minmax(0,1fr);gap:14px}.article-art-small{width:88px;min-height:84px}.article-art-small span{font-size:23px}.article-row h3{font-size:1rem}.article-row p{display:-webkit-box;-webkit-box-orient:vertical;-webkit-line-clamp:2;overflow:hidden;font-size:13px}.article-arrow{display:none}.newsletter-strip{grid-template-columns:auto minmax(0,1fr);padding:20px 0}.newsletter-form,.newsletter-success{grid-column:1/-1}.newsletter-form input{flex:1 1;min-width:0}.article-page{padding-top:88px}.article-page-header{padding-top:24px;grid-template-columns:1fr;gap:24px}.article-art-large{min-height:170px}.article-page-header h1{font-size:2.15rem}.article-body{padding-top:36px}.article-body>p{font-size:1rem}.community-shell{padding:76px 16px 48px;display:block}.community-sidebar{position:static;padding-bottom:18px;border-bottom:1px solid var(--border)}.community-sidebar-note{display:none}.community-nav{display:flex;gap:6px;overflow-x:auto;margin:0 -2px}.community-nav-label{display:none}.community-nav button{width:auto;min-width:max-content;padding-inline:11px;border:1px solid var(--border)}.community-nav button small{display:none}.community-compose-button{width:auto;padding-inline:14px;margin-bottom:14px}.community-feed-header{padding-top:24px}.community-feed-header h1{font-size:2rem}.community-toolbar{min-height:62px;flex-wrap:wrap;padding:8px 0}.community-search{flex-basis:100%}.sort-tabs{margin-left:auto}.community-post.is-featured{margin-inline:-8px;padding-inline:8px}}