:root{--practice-ink: #12211d;--practice-muted: #52625d;--practice-paper: #f4f3ed;--practice-line: #d8ded9;--practice-teal: #176b63;--practice-teal-dark: #0d4742;--practice-gold: #c88f32;--practice-code: #111816;--practice-code-soft: #18211e;--practice-code-line: #2a3732}.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}.practice-landing,.practice-list-page,.practice-guide,.practice-foundations,.practice-skills{color:var(--practice-ink)}.practice-hero{display:grid;grid-template-columns:minmax(0,1.45fr) minmax(300px,.7fr);gap:clamp(40px,7vw,96px);align-items:end;padding:52px 0 76px;border-bottom:1px solid var(--practice-line)}.practice-kicker,.practice-page-header>div>p:first-child,.practice-principles>header>p,.curriculum-section>header p,.foundation-units>header>p,.skill-reading-guide>header>p{margin:0 0 18px;color:var(--practice-teal);font:750 .76rem/1.2 ui-monospace,SFMono-Regular,Menlo,monospace;letter-spacing:.14em}.practice-hero h1{max-width:820px;font-size:clamp(3.3rem,7vw,6.5rem);letter-spacing:-.055em}.practice-hero-copy{max-width:720px;margin:28px 0 0;color:var(--practice-muted);font-size:1.08rem;line-height:2}.practice-hero-actions{display:flex;flex-wrap:wrap;gap:12px;margin-top:34px}.practice-hero-actions a,.practice-page-header>a{display:inline-flex;align-items:center;justify-content:center;gap:20px;min-height:48px;padding:0 20px;border:1px solid var(--practice-ink);background:var(--practice-ink);color:#fff;font-weight:760;text-decoration:none;transition:background .18s ease,color .18s ease,transform .18s ease}.practice-hero-actions a:hover,.practice-hero-actions a:focus-visible,.practice-page-header>a:hover,.practice-page-header>a:focus-visible{background:var(--practice-teal);transform:translateY(-2px)}.practice-hero-actions 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var(--practice-line)}.dashboard-metrics article{padding:30px 28px;border-right:1px solid var(--practice-line)}.dashboard-metrics article:last-child{border-right:0}.dashboard-metrics span,.continue-card>div>span,.curriculum-card header span{color:var(--practice-teal);font:750 .7rem/1.2 ui-monospace,SFMono-Regular,Menlo,monospace;letter-spacing:.12em}.dashboard-metrics strong{display:block;margin-top:10px;font-size:2.6rem;line-height:1}.dashboard-metrics strong small{color:var(--practice-muted);font-size:1rem}.dashboard-metrics p{margin:10px 0 0;color:var(--practice-muted);font-size:.82rem}.continue-card{display:grid;grid-template-columns:1fr auto;gap:28px;align-items:center;margin-top:28px;padding:clamp(24px,4vw,44px);border:1px solid #93bdb5;background:#e5f0ed;color:var(--practice-ink);text-decoration:none;transition:border-color .18s ease,transform .18s ease}.continue-card:hover,.continue-card:focus-visible{border-color:var(--practice-teal);transform:translateY(-2px)}.continue-card h2{margin:12px 0 0;font-size:clamp(1.6rem,3vw,2.4rem)}.continue-card p{margin:10px 0 0;color:var(--practice-muted)}.continue-card>strong{font-size:2.3rem}.curriculum-section{margin-top:80px}.curriculum-section>header,.practice-principles>header{display:flex;align-items:end;justify-content:space-between;gap:32px;margin-bottom:24px}.curriculum-section h2,.practice-principles h2{margin:0;font-size:clamp(2rem,4vw,3.5rem)}.curriculum-section>header a{color:var(--practice-ink);font-weight:730}.curriculum-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));border-top:1px solid var(--practice-line);border-left:1px solid var(--practice-line)}.curriculum-card{min-height:220px;padding:22px;border-right:1px solid var(--practice-line);border-bottom:1px solid var(--practice-line);background:#fff}.curriculum-card[data-available=false]{background:#f8f8f5;color:#69746f}.curriculum-card header{display:flex;justify-content:space-between}.curriculum-card header small{color:var(--practice-muted);font:650 .68rem/1.2 ui-monospace,SFMono-Regular,Menlo,monospace}.curriculum-card h3{margin:44px 0 10px;font-size:1.12rem}.curriculum-card p{margin:0;color:var(--practice-muted);font-size:.82rem;line-height:1.7}.curriculum-progress{height:3px;margin-top:22px;background:#e4e8e5}.curriculum-progress i{display:block;height:100%;background:var(--practice-teal)}.practice-principles{margin-top:96px}.practice-principles ol{display:grid;grid-template-columns:repeat(3,1fr);gap:0;margin:0;padding:0;border-block:1px solid var(--practice-line);list-style:none}.practice-principles li{display:grid;grid-template-columns:auto 1fr;gap:20px;padding:30px 26px;border-right:1px solid var(--practice-line)}.practice-principles li:last-child{border-right:0}.practice-principles li>span{color:var(--practice-teal);font:700 .72rem/1 ui-monospace,SFMono-Regular,Menlo,monospace}.practice-principles h3{margin:0;font-size:1.05rem}.practice-principles li p{margin:9px 0 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ui-monospace,SFMono-Regular,Menlo,monospace;letter-spacing:.06em;text-transform:uppercase}.difficulty-easy{color:#1b7368}.difficulty-medium{color:#9b650e}.difficulty-hard{color:#a53c3c}.problem-status{color:var(--practice-muted);font-size:.78rem}.problem-status-ac{color:var(--practice-teal);font-weight:750}.problem-status-attempted{color:#9b650e}.problem-row-arrow{font-size:1.2rem;text-align:right}.upcoming-curriculum{display:grid;grid-template-columns:auto 1fr auto;gap:28px;align-items:center;margin-top:28px;padding:28px;border:1px solid var(--practice-line);background:#f3f5f2}.upcoming-curriculum>span{color:var(--practice-teal);font:720 .7rem/1 ui-monospace,SFMono-Regular,Menlo,monospace}.upcoming-curriculum h2{margin:0;font-size:1.15rem}.upcoming-curriculum p{margin:8px 0 0;color:var(--practice-muted);font-size:.86rem}.upcoming-curriculum a{color:var(--practice-ink);font-weight:720}.practice-problem-page{overflow:hidden;border:1px solid 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ui-monospace,SFMono-Regular,Menlo,monospace}.practice-editor-mount{z-index:1}@keyframes editor-pulse{50%{opacity:.45}}.practice-results{display:grid;grid-template-rows:auto 1fr;min-height:0;background:#151e1b}.practice-results-header{display:flex;align-items:center;justify-content:space-between;min-height:42px;padding:0 14px;border-bottom:1px solid var(--practice-code-line)}.practice-results-header [role=tablist]{display:flex;align-self:stretch}.practice-results-header button{min-width:90px;border:0;border-bottom:2px solid transparent;background:transparent;color:#7f8e89;font:700 .7rem/1 ui-monospace,SFMono-Regular,Menlo,monospace;cursor:pointer}.practice-results-header button[aria-selected=true]{border-color:#6fc8bd;color:#dfe9e5}.practice-results-header button 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