:root{--lightningcss-light:initial;--lightningcss-dark: ;color-scheme:light;--bg:#f5f8fb;--bg-elevated:#fff;--panel:#fff;--panel-strong:#eef4f8;--panel-soft:#e5edf4;--surface-glass:#ffffffc7;--text:#122033;--muted:#5c6c80;--line:#d6e0ea;--accent:#15b77f;--accent-strong:#0f9f6f;--warning:#f7b955;--danger:#d94f5c;--code:#101927;--code-text:#f7fafc;--focus:#2d7ff9;--shadow:#1a293d1f;--shadow-soft:#1a293d14;--cta-bg:#0a6b4e;--cta-bg-hover:#085c43;--cta-text:#fff;--eyebrow:#0c7a55;--ink-mix-color:#0c1822;--ink-mix-amount:34%;--font-display:"Fraunces", "Iowan Old Style", Georgia, serif;--font-body:"Instrument Sans", ui-sans-serif, system-ui, -apple-system, "Segoe UI", sans-serif;font-family:var(--font-body)}@media (prefers-color-scheme:dark){:root:not([data-theme]){--lightningcss-light: ;--lightningcss-dark:initial;color-scheme:dark;--bg:#111827;--bg-elevated:#182332;--panel:#202c3a;--panel-strong:#2b3848;--panel-soft:#364557;--surface-glass:#192432c7;--text:#f7fafc;--muted:#b8c4d2;--line:#465568;--accent:#20c997;--accent-strong:#18ad80;--warning:#f7b955;--danger:#f07178;--code:#0b1420;--code-text:#f7fafc;--focus:#69a7ff;--shadow:#02061757;--shadow-soft:#0206173d;--cta-bg:#2fdfa3;--cta-bg-hover:#56e8b6;--cta-text:#052e21;--eyebrow:#4ee6ae;--ink-mix-color:#fff;--ink-mix-amount:42%}}:root[data-theme=dark]{--lightningcss-light: ;--lightningcss-dark:initial;color-scheme:dark;--bg:#111827;--bg-elevated:#182332;--panel:#202c3a;--panel-strong:#2b3848;--panel-soft:#364557;--surface-glass:#192432c7;--text:#f7fafc;--muted:#b8c4d2;--line:#465568;--accent:#20c997;--accent-strong:#18ad80;--warning:#f7b955;--danger:#f07178;--code:#0b1420;--code-text:#f7fafc;--focus:#69a7ff;--shadow:#02061757;--shadow-soft:#0206173d;--cta-bg:#2fdfa3;--cta-bg-hover:#56e8b6;--cta-text:#052e21;--eyebrow:#4ee6ae;--ink-mix-color:#fff;--ink-mix-amount:42%}:root[data-theme=light]{--lightningcss-light:initial;--lightningcss-dark: ;color-scheme:light}*{box-sizing:border-box}body{background:var(--bg);min-width:320px;color:var(--text);margin:0}button,input,textarea{font:inherit}button{cursor:pointer}button:disabled{cursor:not-allowed;opacity:.48}.topic-page{background:radial-gradient(820px 480px at 12% -4%, #15b77f24, transparent), radial-gradient(900px 540px at 96% 12%, #b453091a, transparent), radial-gradient(color-mix(in srgb, var(--line), transparent 35%) 1px, transparent 1px), var(--bg);min-height:100vh;color:var(--text);background-size:auto,auto,26px 26px,auto;padding:24px clamp(18px,4vw,64px) 40px}.topic-topbar{justify-content:space-between;align-items:center;gap:18px;max-width:1480px;margin:0 auto 56px;display:flex}.brand-chip{border:1px solid var(--line);background:var(--surface-glass);color:var(--text);font-family:var(--font-display);letter-spacing:.01em;box-shadow:0 12px 28px var(--shadow-soft);border-radius:999px;align-items:center;gap:10px;padding:10px 18px;font-size:1.02rem;font-weight:700;display:inline-flex}.brand-chip:before{content:"";background:var(--accent);width:10px;height:10px;box-shadow:0 0 0 4px color-mix(in srgb, var(--accent), transparent 78%);border-radius:50%}.theme-toggle{border:1px solid var(--line);background:var(--surface-glass);width:max-content;box-shadow:0 12px 28px var(--shadow-soft);border-radius:999px;gap:4px;padding:4px;display:inline-flex}.theme-toggle button{min-height:32px;color:var(--muted);text-transform:capitalize;background:0 0;border:0;border-radius:999px;padding:0 12px;font-size:.78rem;font-weight:700}.theme-toggle button:hover,.theme-toggle button.active{background:var(--accent);color:#04281c}.topic-hero{grid-template-columns:minmax(0,1fr) minmax(300px,440px);align-items:center;gap:clamp(26px,5vw,72px);max-width:1480px;margin:0 auto 72px;animation:.64s cubic-bezier(.2,.7,.2,1) both hero-rise;display:grid}@keyframes hero-rise{0%{opacity:0;transform:translateY(14px)}to{opacity:1;transform:translateY(0)}}.topic-hero-copy{max-width:780px}.topic-hero .eyebrow,.topic-toolbar .eyebrow{color:var(--eyebrow);letter-spacing:.14em;font-weight:700}.topic-hero h1{color:var(--text);font-family:var(--font-display);letter-spacing:-.015em;text-wrap:balance;margin:14px 0 20px;font-size:clamp(2.7rem,5.4vw,4.9rem);font-weight:640;line-height:1.04}.topic-hero h1 em{color:var(--eyebrow);font-style:italic;font-weight:600}.topic-hero-lead{max-width:660px;color:var(--muted);margin:0 0 28px;font-size:1.12rem;line-height:1.75}.hero-actions{flex-wrap:wrap;align-items:center;gap:12px;margin-bottom:26px;display:flex}.hero-cta{background:var(--cta-bg);color:var(--cta-text);box-shadow:0 16px 36px color-mix(in srgb, var(--cta-bg), transparent 64%);border:0;border-radius:999px;padding:15px 30px;font-size:1.02rem;font-weight:700;transition:background .16s,transform .16s}.hero-cta:hover{background:var(--cta-bg-hover);transform:translateY(-1px)}.hero-secondary{border:1px solid var(--line);background:var(--surface-glass);color:var(--text);border-radius:999px;align-items:center;padding:14px 24px;font-weight:700;text-decoration:none;transition:border-color .16s,background .16s;display:inline-flex}.hero-secondary:hover{border-color:var(--eyebrow);background:var(--panel)}.hero-features{flex-wrap:wrap;gap:8px 20px;margin:0;padding:0;list-style:none;display:flex}.hero-features li{color:var(--muted);align-items:center;gap:8px;font-size:.92rem;font-weight:600;display:inline-flex}.hero-features li:before{content:"";background:var(--eyebrow);border-radius:50%;width:6px;height:6px}.topic-stats{grid-template-columns:repeat(2,minmax(0,1fr));gap:14px;display:grid}.topic-stats div{border:1px solid var(--line);background:var(--surface-glass);min-height:128px;box-shadow:0 18px 42px var(--shadow-soft);border-radius:14px;padding:22px 20px 18px;position:relative;overflow:hidden}.topic-stats div:after{content:"";background:linear-gradient(90deg, var(--accent), transparent 80%);height:3px;position:absolute;inset:auto 0 0}.topic-stats strong{color:var(--text);font-family:var(--font-display);font-size:2.5rem;font-weight:640;line-height:1;display:block}.topic-stats span{color:var(--muted);margin-top:10px;font-size:.88rem;font-weight:600;line-height:1.45;display:block}.topic-toolbar{justify-content:space-between;align-items:end;gap:24px;max-width:1480px;margin:0 auto 22px;display:flex}.topic-toolbar h2{color:var(--text);font-family:var(--font-display);letter-spacing:-.01em;margin:6px 0 0;font-size:clamp(1.7rem,3vw,2.5rem);font-weight:640}.topic-search{gap:8px;width:min(100%,430px);display:grid}.topic-search span{color:var(--muted);font-size:.84rem;font-weight:700}.topic-search input{border:1px solid var(--line);background:var(--panel);min-height:54px;color:var(--text);box-shadow:0 10px 26px var(--shadow-soft);border-radius:12px;font-family:inherit;font-size:1rem}.topic-notice{border-left:4px solid var(--warning);background:color-mix(in srgb, var(--warning), var(--panel) 84%);max-width:1480px;color:var(--text);border-radius:8px;margin:0 auto 18px;padding:14px 16px;font-weight:700}.topic-grid{grid-template-columns:repeat(auto-fit,minmax(264px,1fr));gap:18px;max-width:1480px;margin:0 auto;scroll-margin-top:24px;display:grid}.topic-card{--topic-ink:color-mix(in srgb, var(--topic-accent), var(--ink-mix-color) var(--ink-mix-amount));border:1px solid color-mix(in srgb, var(--topic-accent), var(--line) 55%);background:linear-gradient(180deg, color-mix(in srgb, var(--topic-accent), transparent 92%), transparent 46%), var(--panel);min-height:276px;color:var(--text);text-align:left;box-shadow:0 14px 34px var(--shadow-soft);border-radius:14px;align-content:start;justify-items:start;gap:10px;padding:24px 22px 22px;transition:border-color .18s,box-shadow .18s,transform .18s;animation:.52s cubic-bezier(.2,.7,.2,1) both card-rise;display:grid;position:relative;overflow:hidden}.topic-card:before{content:"";background:var(--topic-accent);height:4px;position:absolute;inset:0 0 auto}.topic-card:first-child{animation-delay:60ms}.topic-card:nth-child(2){animation-delay:.11s}.topic-card:nth-child(3){animation-delay:.16s}.topic-card:nth-child(4){animation-delay:.21s}.topic-card:nth-child(5){animation-delay:.26s}.topic-card:nth-child(6){animation-delay:.31s}.topic-card:nth-child(7){animation-delay:.36s}.topic-card:nth-child(8){animation-delay:.41s}.topic-card:nth-child(9){animation-delay:.46s}.topic-card:nth-child(10){animation-delay:.51s}@keyframes card-rise{0%{opacity:0;transform:translateY(16px)}to{opacity:1;transform:translateY(0)}}.topic-card:hover{border-color:var(--topic-ink);box-shadow:0 22px 48px var(--shadow), 0 6px 22px color-mix(in srgb, var(--topic-accent), transparent 72%);transform:translateY(-4px)}.topic-card:focus-visible{outline:3px solid var(--focus);outline-offset:3px}.topic-status{border:1px solid color-mix(in srgb, var(--topic-ink), transparent 50%);background:color-mix(in srgb, var(--topic-accent), var(--panel) 90%);color:var(--topic-ink);letter-spacing:.08em;text-transform:uppercase;border-radius:999px;padding:5px 10px;font-size:.72rem;font-weight:700;position:absolute;top:18px;right:16px}.topic-mark{border:1px solid color-mix(in srgb, var(--topic-ink), transparent 60%);background:color-mix(in srgb, var(--topic-accent), var(--panel) 86%);width:58px;height:58px;color:var(--topic-ink);border-radius:12px;place-items:center;margin-bottom:4px;font-size:1.3rem;font-weight:700;display:grid}.topic-title{color:var(--text);font-family:var(--font-display);letter-spacing:-.01em;font-size:1.55rem;font-weight:640}.topic-label{color:var(--text);font-weight:700}.topic-description{color:var(--muted);font-size:.94rem;line-height:1.6}.topic-action{color:var(--topic-ink);align-self:end;margin-top:12px;font-weight:700}.topic-footer{border-top:1px solid var(--line);max-width:1480px;margin:48px auto 0;padding-top:22px}.topic-footer p{color:var(--muted);margin:0;font-size:.92rem}@media (prefers-reduced-motion:reduce){.topic-hero,.topic-card{animation:none}.topic-card,.hero-cta,.hero-secondary{transition:none}.topic-card:hover,.hero-cta:hover{transform:none}}.topic-back-button{border:1px solid var(--line);width:100%;min-height:38px;color:var(--muted);background:0 0;border-radius:8px;margin-top:16px;font-size:.86rem;font-weight:900}.topic-back-button:hover{background:var(--panel);color:var(--text)}.app-shell{background:var(--bg);grid-template-columns:360px minmax(0,1fr);min-height:100vh;display:grid}.sidebar{border-right:1px solid var(--line);background:color-mix(in srgb, var(--bg-elevated), var(--bg) 24%);padding:28px 20px;overflow-y:auto}.brand-block{gap:10px;margin-bottom:24px;display:grid}.brand-block .theme-toggle{margin-bottom:8px}.set-switcher{gap:8px;margin-bottom:20px;display:grid}.set-button{background:var(--panel);width:100%;min-height:50px;color:var(--text);text-align:left;border:1px solid #0000;border-radius:8px;gap:2px;padding:9px 12px;display:grid}.set-button span{font-weight:900}.set-button small{color:var(--muted);font-weight:700}.set-button:hover,.set-button.active{border-color:var(--accent);background:var(--panel-strong)}.eyebrow{color:var(--accent);letter-spacing:.08em;text-transform:uppercase;margin:0 0 8px;font-size:.76rem;font-weight:800}h1,h2,p{margin-top:0}h1{margin-bottom:0;font-size:2rem;line-height:1.08}h2{max-width:980px;margin-bottom:0;font-size:2rem;line-height:1.22}.overall-progress{margin-bottom:22px}.reset-button{border:1px solid var(--line);width:100%;min-height:34px;color:var(--muted);background:0 0;border-radius:8px;margin-top:10px;font-size:.84rem;font-weight:800}.reset-button:hover{background:var(--panel);color:var(--text)}.progress-copy{color:var(--muted);justify-content:space-between;margin-bottom:8px;font-size:.9rem;font-weight:700;display:flex}.track{background:var(--panel-soft);border-radius:999px;height:9px;overflow:hidden}.track-fill{border-radius:inherit;background:var(--accent);height:100%;transition:width .18s}.module-list{grid-template-columns:minmax(0,1fr);gap:8px;display:grid}.module-button{min-width:0}.module-button,.choice,.primary-button,.secondary-button,.ghost-button{color:var(--text);border:0}.module-button{width:100%;min-height:46px;color:var(--muted);text-align:left;background:0 0;border-radius:8px;justify-content:space-between;align-items:center;gap:12px;padding:10px 12px;display:flex}.module-button span:first-child{text-overflow:ellipsis;white-space:nowrap;min-width:0;overflow:hidden}.module-button span:last-child{color:var(--muted);flex:none;font-size:.82rem;font-weight:800}.module-button:hover,.module-button.active{background:var(--panel);color:var(--text)}.quiz-area{align-content:start;gap:24px;padding:48px clamp(22px,5vw,72px);display:grid}.quiz-topline{justify-content:space-between;align-items:flex-start;gap:24px;display:flex}.question-meta{flex:none;gap:8px;padding-top:6px;display:flex}.question-meta span{border:1px solid var(--line);color:var(--muted);border-radius:999px;padding:8px 12px;font-size:.82rem;font-weight:800}.choice-list{gap:12px;max-width:1040px;display:grid}.two-choice{max-width:680px}.choice{background:var(--panel-soft);text-align:left;border:2px solid #0000;border-radius:8px;align-items:center;gap:16px;min-height:74px;padding:16px 22px;transition:background .15s,border-color .15s,transform .15s;display:flex}.choice:hover{background:var(--panel-strong)}.radio-dot{border:2px solid var(--text);background:var(--text);width:22px;height:22px;box-shadow:inset 0 0 0 5px var(--panel-soft);border-radius:50%;flex:none;place-items:center;display:inline-grid}.choice.selected .radio-dot{background:var(--accent);box-shadow:inset 0 0 0 4px var(--panel-strong)}.choice span:last-child{overflow-wrap:anywhere;font-family:SFMono-Regular,Consolas,Liberation Mono,monospace;font-size:clamp(1rem,1.8vw,1.35rem);line-height:1.4}.code-task{gap:16px;max-width:1080px;display:grid}pre,textarea,input{border:1px solid var(--line);background:var(--code);color:var(--code-text);border-radius:8px;font-family:SFMono-Regular,Consolas,Liberation Mono,monospace;font-size:clamp(.92rem,1.6vw,1.2rem);line-height:1.65}pre{white-space:pre-wrap;margin:0;padding:22px;overflow-x:auto}textarea{resize:vertical;width:100%;min-height:250px;padding:18px}input{width:100%;min-height:48px;padding:8px 12px}textarea:focus,input:focus,button:focus-visible{outline:3px solid var(--focus);outline-offset:2px}.blank-grid{grid-template-columns:repeat(auto-fit,minmax(190px,1fr));gap:12px;display:grid}.blank-grid label{gap:8px;display:grid}.blank-grid span{color:var(--muted);font-size:.86rem;font-weight:800}.feedback{border-left:5px solid var(--warning);background:var(--panel);border-radius:8px;max-width:1080px;padding:18px 20px}.feedback.correct{border-left-color:var(--accent)}.feedback.incorrect{border-left-color:var(--danger)}.feedback strong{margin-bottom:6px;font-size:1.05rem;display:block}.feedback p{color:var(--muted);margin-bottom:12px;line-height:1.6}.feedback pre{margin-top:10px}.actions{justify-content:space-between;align-items:center;gap:12px;max-width:1080px;padding-top:4px;display:flex}.action-cluster{gap:10px;display:flex}.primary-button,.secondary-button,.ghost-button{border-radius:8px;min-height:46px;padding:0 18px;font-weight:800}.primary-button{background:var(--accent)}.secondary-button,.ghost-button{background:var(--panel-soft)}.ghost-button{color:var(--text)}.secondary-button:hover,.ghost-button:hover{background:var(--panel-strong)}@media (width<=980px){.topic-hero{grid-template-columns:1fr}.topic-toolbar{flex-direction:column;align-items:stretch}.app-shell{grid-template-columns:1fr}.sidebar{border-right:0;border-bottom:1px solid var(--line);max-height:none;padding:22px}.module-list{grid-template-columns:repeat(2,minmax(0,1fr))}.quiz-topline,.actions{flex-direction:column;align-items:stretch}.question-meta,.action-cluster{justify-content:flex-start}}@media (width<=640px){.topic-page{padding:28px 14px 40px}.topic-stats{grid-template-columns:1fr}.topic-card{min-height:auto}h1{font-size:1.55rem}h2{font-size:1.35rem}.quiz-area{padding:28px 16px}.module-list{grid-template-columns:1fr}.choice{min-height:62px;padding:14px}.actions,.action-cluster{grid-template-columns:1fr;display:grid}}.py-run-panel{gap:12px;display:grid}.py-run-row{align-items:center;gap:14px;display:flex}.py-run-hint{color:var(--muted);font-size:.85rem}.py-console{border:1px solid var(--line);background:var(--code);border-radius:8px;gap:2px;max-height:320px;padding:14px 16px;display:grid;overflow-y:auto}.py-console pre{background:0 0;border:0;border-radius:0;padding:2px 0;font-size:.95rem;line-height:1.5}.py-out{color:var(--code-text)}.py-value{color:#8fd3ff}.py-error{color:var(--danger)}.py-info{color:var(--muted);font-style:italic}.py-code{color:#7ee2b8;font-weight:700}.playground-shell{align-content:start;gap:24px;min-height:100vh;padding:40px clamp(20px,5vw,72px);display:grid}.playground-topline{justify-content:space-between;align-items:flex-start;gap:24px;display:flex}.playground-topline h1{margin:4px 0 8px}.playground-subtitle{max-width:640px;color:var(--muted);line-height:1.6}.playground-grid{grid-template-columns:minmax(0,1.1fr) minmax(0,1fr);gap:20px;display:grid}.playground-editor,.playground-console-wrap{border:1px solid var(--line);background:var(--panel);border-radius:10px;align-content:start;gap:12px;padding:16px;display:grid}.playground-editor-toolbar{flex-wrap:wrap;gap:10px;display:flex}.playground-code{min-height:380px}.playground-console{border:1px solid var(--line);background:var(--code);border-radius:8px;align-content:start;gap:2px;min-height:330px;max-height:440px;padding:14px 16px;display:grid;overflow-y:auto}.playground-console pre{background:0 0;border:0;border-radius:0;padding:2px 0;font-size:.95rem;line-height:1.5}.playground-repl{align-items:center;gap:10px;display:flex}.playground-repl span{color:#7ee2b8;font-family:SFMono-Regular,Consolas,Liberation Mono,monospace;font-weight:700}.playground-button{border:1px solid var(--accent);color:var(--accent);background:0 0;border-radius:999px;justify-self:start;margin-top:10px;padding:9px 16px;font-size:.85rem;font-weight:800}.tutor-toggle{border:1px dashed var(--line);background:var(--panel);max-width:1080px;color:var(--text);border-radius:10px;justify-self:start;padding:14px 22px;font-weight:800}.tutor-panel{border:1.5px solid color-mix(in srgb, var(--track-accent,var(--accent)), var(--line) 35%);border-top:4px solid var(--track-accent,var(--accent));background:var(--panel);max-width:1080px;box-shadow:0 10px 30px color-mix(in srgb, var(--track-accent,var(--accent)), transparent 88%);border-radius:12px;gap:14px;padding:18px 20px;display:grid}.tutor-header{justify-content:space-between;align-items:center;gap:12px;display:flex}.tutor-header strong{font-size:1.05rem}.tutor-header-actions{flex-wrap:wrap;gap:8px;display:flex}.tutor-header-actions .ghost-button{min-height:38px;padding:0 12px;font-size:.85rem}.tutor-settings{border:1px solid var(--line);background:var(--panel-strong);border-radius:8px;gap:12px;padding:14px;display:grid}.tutor-settings label{gap:6px;display:grid}.tutor-settings span{color:var(--muted);font-size:.85rem;font-weight:700}.tutor-log{align-content:start;gap:10px;max-height:420px;padding:2px;display:grid;overflow-y:auto}.tutor-empty p{color:var(--muted);margin:0 0 12px;line-height:1.6}.tutor-starters{flex-wrap:wrap;gap:8px;display:flex}.tutor-starters button{border:1px solid var(--line);background:var(--panel-soft);color:var(--text);border-radius:999px;padding:8px 14px;font-size:.85rem;font-weight:700}.tutor-message{border-radius:10px;max-width:92%;padding:10px 14px;line-height:1.6}.tutor-message.user{background:var(--panel-soft);justify-self:end}.tutor-message.assistant{border:1px solid var(--line);background:var(--panel-strong);justify-self:start}.tutor-message.thinking{color:var(--muted);font-style:italic}.tutor-message-body p{white-space:pre-wrap;margin:0 0 8px}.tutor-message-body p:last-child{margin-bottom:0}.tutor-message-body pre{margin:8px 0;padding:12px 14px;font-size:.92rem}.tutor-error{color:var(--danger);margin:0;font-size:.9rem}.tutor-input-row{gap:10px;display:flex}.tutor-input-row input{flex:1}@media (width<=980px){.playground-grid{grid-template-columns:1fr}.playground-topline{flex-direction:column;align-items:stretch}.playground-code{min-height:260px}}.search-results{grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:10px;max-width:1480px;margin:0 auto 18px;display:grid}.search-result{border:1px solid var(--line);background:var(--panel);text-align:left;border-radius:10px;gap:4px;padding:12px 16px;display:grid}.search-result:hover{border-color:var(--accent)}.search-result strong{color:var(--text)}.search-result span{color:var(--muted);font-size:.82rem}.lesson-panel{border:1px solid var(--line);background:var(--panel);border-radius:10px;max-width:1080px;overflow:hidden}.lesson-toggle{width:100%;color:var(--text);text-align:left;background:0 0;border:0;justify-content:space-between;align-items:center;gap:12px;padding:14px 18px;font-weight:800;display:flex}.lesson-toggle span:last-child{color:var(--accent);font-size:.85rem}.lesson-body{border-top:1px solid var(--line);gap:14px;padding:18px;display:grid}.lesson-body p{color:var(--muted);margin:0;line-height:1.7}.lesson-body ul{color:var(--muted);gap:6px;margin:0;padding-left:20px;line-height:1.6;display:grid}.lesson-example{gap:12px;display:grid}.module-button.review{border:1px dashed var(--warning)}.module-button.review span:last-child{color:var(--warning)}.exam-button{border:1px solid var(--focus);min-height:44px;color:var(--focus);background:0 0;border-radius:8px;font-weight:800}.tutor-nudge{border-left:4px solid var(--warning);background:var(--panel);max-width:1080px;color:var(--muted);border-radius:6px;margin:0;padding:12px 16px}.grade-method{color:var(--accent);font-size:.9rem}.grade-compare{grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:12px;margin-top:12px;display:grid}.grade-compare span{color:var(--muted);text-transform:uppercase;margin-bottom:6px;font-size:.82rem;font-weight:800;display:block}.empty-state{justify-items:start;gap:12px;max-width:640px;display:grid}.empty-state p{color:var(--muted);margin:0;line-height:1.6}.exam-shell{align-content:start;gap:24px;min-height:100vh;padding:48px clamp(20px,6vw,96px);display:grid}.exam-card{border:1px solid var(--line);background:var(--panel);border-radius:12px;gap:14px;max-width:720px;padding:28px;display:grid}.exam-card p{color:var(--muted);margin:0;line-height:1.7}.exam-actions{flex-wrap:wrap;gap:10px;display:flex}.exam-topbar{justify-content:space-between;align-items:flex-start;gap:24px;max-width:1080px;display:flex}.exam-progress{color:var(--muted);font-size:.9rem;font-weight:700}.exam-quit{justify-self:start}.exam-score{margin:0;font-size:3.4rem}.exam-score.passed{color:var(--accent)}.exam-score.failed{color:var(--danger)}.exam-review{gap:16px;max-width:920px;display:grid}.exam-miss{border:1px solid var(--line);border-left:4px solid var(--danger);background:var(--panel);border-radius:10px;gap:10px;padding:16px 18px;display:grid}.exam-miss p{color:var(--muted);margin:0;line-height:1.6}.certificate-name{gap:6px;max-width:420px;display:grid}.certificate-name span{color:var(--muted);font-size:.85rem;font-weight:700}.certificate{border:6px double var(--accent);color:#1d2733;text-align:center;background:#fdfbf4;border-radius:14px;justify-items:center;gap:10px;max-width:820px;padding:56px 40px;display:grid}.certificate h1{color:#1d2733;margin:0}.certificate-brand{letter-spacing:.3em;text-transform:uppercase;color:#8a7b4d;margin:0;font-size:.8rem;font-weight:800}.certificate-awarded{color:#5b6575;margin:0}.certificate-holder{border-bottom:2px solid #c9bd96;margin:4px 0;padding:0 28px 6px;font-size:2rem;font-weight:800}.certificate-set{margin:0;font-weight:700}.certificate-score{color:#0f9f6f;margin:0;font-weight:800}.certificate-date{color:#5b6575;margin:8px 0 0;font-size:.9rem}@media print{body *{visibility:hidden}.certificate,.certificate *{visibility:visible}.certificate{border-radius:0;height:fit-content;margin:auto;position:fixed;inset:0}}.projects-shell{align-content:start;gap:24px;min-height:100vh;padding:40px clamp(20px,5vw,72px);display:grid}.project-grid{grid-template-columns:repeat(auto-fill,minmax(290px,1fr));gap:18px;display:grid}.project-card{border:1px solid var(--line);background:var(--panel);color:var(--text);text-align:left;border-radius:12px;align-content:start;gap:10px;padding:22px;display:grid}.project-card strong{font-size:1.15rem}.project-card p{color:var(--muted);margin:0;line-height:1.6}.project-level{border:1px solid var(--line);color:var(--muted);border-radius:999px;justify-self:start;padding:4px 10px;font-size:.78rem;font-weight:800}.project-progress{color:var(--accent);font-size:.85rem;font-weight:800}.project-header-actions{gap:10px;display:flex}.project-layout{grid-template-columns:280px minmax(0,1fr);gap:20px;display:grid}.project-steps{align-content:start;gap:8px;display:grid}.project-step{border:1px solid var(--line);background:var(--panel);color:var(--text);text-align:left;border-radius:8px;align-items:center;gap:12px;padding:12px 14px;font-weight:700;display:flex}.project-step span:first-child{border:1px solid var(--line);border-radius:50%;flex:none;place-items:center;width:26px;height:26px;font-size:.8rem;display:inline-grid}.project-step.active{border-color:var(--accent)}.project-step.done span:first-child{border-color:var(--accent);background:var(--accent);color:#fff}.project-work{border:1px solid var(--line);background:var(--panel);border-radius:12px;align-content:start;gap:14px;padding:20px;display:grid}.project-work h2{align-items:center;gap:12px;margin:0;display:flex}.step-done-badge{background:var(--accent);color:#fff;border-radius:999px;padding:4px 12px;font-size:.75rem;font-weight:800}.project-instructions{color:var(--muted);margin:0;line-height:1.7}.project-editor{min-height:280px}.project-hint{border-left:4px solid var(--warning);background:var(--panel-strong);color:var(--muted);border-radius:6px;margin:0;padding:12px 16px;line-height:1.6}.sidebar-extras{flex-wrap:wrap;gap:8px;display:flex}@media (width<=980px){.project-layout{grid-template-columns:1fr}.exam-topbar{flex-direction:column;align-items:stretch}}.app-shell,.playground-shell,.projects-shell,.exam-shell{--ta:var(--track-accent,var(--accent));--track-ink:color-mix(in srgb, var(--ta), var(--ink-mix-color) var(--ink-mix-amount))}.quiz-area{background:radial-gradient(720px 360px at 88% -6%, color-mix(in srgb, var(--ta), transparent 93%), transparent), radial-gradient(color-mix(in srgb, var(--line), transparent 55%) 1px, transparent 1px);background-size:auto,26px 26px}.playground-shell,.projects-shell,.exam-shell{background:radial-gradient(720px 360px at 85% -6%, color-mix(in srgb, var(--ta), transparent 92%), transparent), radial-gradient(color-mix(in srgb, var(--line), transparent 55%) 1px, transparent 1px), var(--bg);background-size:auto,26px 26px,auto}.brand-block h1,.quiz-topline h2,.playground-topline h1,.projects-shell .project-work h2,.exam-card h1,.exam-topbar h2,.empty-state h2{font-family:var(--font-display);letter-spacing:-.01em;font-weight:640}.quiz-topline h2{text-wrap:balance;line-height:1.18}.sidebar{border-right:1px solid color-mix(in srgb, var(--ta), var(--line) 70%)}.brand-block .eyebrow,.quiz-topline .eyebrow{color:var(--track-ink);letter-spacing:.14em}.set-button,.module-button{border-radius:12px}.set-button.active{border-color:var(--track-ink);background:linear-gradient(180deg, color-mix(in srgb, var(--ta), transparent 90%), transparent 70%), var(--panel)}.set-button.active span{color:var(--track-ink)}.module-button.active{border:1px solid color-mix(in srgb, var(--track-ink), transparent 35%);background:linear-gradient(90deg, color-mix(in srgb, var(--ta), transparent 88%), transparent 80%), var(--panel)}.module-button.active span:first-child{color:var(--text)}.module-button span:last-child{color:var(--track-ink);font-weight:700}.track{border-radius:999px;overflow:hidden}.track-fill{background:linear-gradient(90deg, var(--ta), color-mix(in srgb, var(--ta), var(--accent) 60%));border-radius:999px}.exam-button{border:1px solid color-mix(in srgb, var(--track-ink), transparent 35%);color:var(--track-ink);border-radius:999px}.exam-button:hover{background:color-mix(in srgb, var(--ta), transparent 90%)}.playground-button{border-color:color-mix(in srgb, var(--track-ink), transparent 35%);color:var(--track-ink)}.playground-button:hover{background:color-mix(in srgb, var(--ta), transparent 90%)}.choice{border-radius:12px}.choice.selected{border-color:var(--track-ink);background:linear-gradient(180deg, color-mix(in srgb, var(--ta), transparent 92%), transparent 70%), var(--panel-strong)}.choice.selected .radio-dot{background:var(--track-ink)}.question-meta span{border-radius:999px}.question-meta span:first-child{border-color:color-mix(in srgb, var(--track-ink), transparent 45%);background:color-mix(in srgb, var(--ta), var(--panel) 92%);color:var(--track-ink)}.lesson-panel{border-top:4px solid var(--ta);border-radius:14px}.lesson-toggle span:last-child{color:var(--track-ink)}.feedback,.tutor-panel,.exam-card,.exam-miss,.project-card,.project-work,.playground-editor,.playground-console-wrap{border-radius:14px}pre,textarea,.py-console,.playground-console{border-radius:12px}.primary-button,.secondary-button,.ghost-button{border-radius:999px;padding:0 22px;font-weight:700}.primary-button{background:var(--cta-bg);color:var(--cta-text)}.primary-button:hover{background:var(--cta-bg-hover)}.secondary-button,.ghost-button{border:1px solid var(--line);background:var(--surface-glass);color:var(--text)}.secondary-button:hover,.ghost-button:hover{border-color:var(--track-ink);background:var(--panel);color:var(--text)}.reset-button,.topic-back-button{border-radius:999px}.topic-back-button:hover{border-color:var(--track-ink);color:var(--track-ink)}.tutor-toggle{border-radius:999px}.tutor-toggle:hover{border-color:var(--track-ink);color:var(--track-ink)}.tutor-starters button{font-weight:700}.tutor-starters button:hover{border-color:var(--track-ink)}.project-step{border-radius:12px}.project-step.active{border-color:var(--track-ink);background:linear-gradient(90deg, color-mix(in srgb, var(--ta), transparent 90%), transparent 75%), var(--panel)}.project-level{color:var(--track-ink);border-color:color-mix(in srgb, var(--track-ink), transparent 50%)}.project-card:hover{border-color:var(--track-ink)}.exam-record strong{color:var(--track-ink)}.certificate h1,.certificate-holder{font-family:var(--font-display)}.certificate h1{font-weight:700}.certificate-holder{font-style:italic;font-weight:640}@media (prefers-reduced-motion:reduce){.primary-button,.secondary-button,.ghost-button,.choice,.module-button,.set-button{transition:none}}.sql-result{background:#0b1420;border:1px solid #ffffff14;border-radius:12px;max-height:360px;padding:14px 16px;overflow:auto}.sql-table-wrap{gap:8px;display:grid}.sql-table{border-collapse:collapse;color:#d7e3ef;width:100%;font-family:SFMono-Regular,Consolas,Liberation Mono,monospace;font-size:.9rem}.sql-table th,.sql-table td{text-align:left;border:1px solid #ffffff1a;padding:6px 12px}.sql-table th{color:#8fd3ff;background:#ffffff0f;font-weight:700}.sql-table tbody tr:nth-child(2n){background:#ffffff08}.sql-rowcount{color:var(--muted);margin:0;font-size:.82rem}.js-preview{border:1px solid var(--line);background:var(--panel,var(--bg));border-radius:8px;gap:8px;padding:16px 18px;font-size:.95rem;display:grid}.js-preview-hidden{display:none}.js-preview h1,.js-preview h2,.js-preview h3{margin:0;font-size:1.1rem}.js-preview p,.js-preview ul,.js-preview div{margin:0}.js-preview ul{padding-left:20px}.js-preview button,.js-preview input{font:inherit;border:1px solid var(--line);background:var(--code);color:inherit;border-radius:6px;justify-self:start;padding:4px 12px}.path-grid{grid-template-columns:repeat(auto-fit,minmax(320px,1fr));gap:18px;max-width:1480px;margin:0 auto;scroll-margin-top:24px;display:grid}.learning-path{border:1px solid var(--line);background:var(--panel);box-shadow:0 14px 34px var(--shadow-soft);border-radius:14px;align-content:start;gap:18px;padding:26px 22px 22px;animation:.52s cubic-bezier(.2,.7,.2,1) both card-rise;display:grid}.learning-path:first-child{animation-delay:60ms}.learning-path:nth-child(2){animation-delay:.14s}.learning-path:nth-child(3){animation-delay:.22s}.path-header{gap:6px;display:grid}.path-header h3{font-family:var(--font-display,inherit);margin:0;font-size:1.35rem}.path-header p{color:var(--muted);margin:0;font-size:.95rem}.path-steps{gap:10px;margin:0;padding:0;list-style:none;display:grid}.path-steps li{position:relative}.path-steps li:not(:last-child):after{content:"";border-left:2px dashed var(--line);height:10px;position:absolute;top:100%;left:31px}.path-step{--topic-ink:color-mix(in srgb, var(--topic-accent), var(--ink-mix-color) var(--ink-mix-amount));border:1px solid color-mix(in srgb, var(--topic-accent), var(--line) 70%);border-left:4px solid var(--topic-accent);background:linear-gradient(90deg, color-mix(in srgb, var(--topic-accent), transparent 94%), transparent 50%), var(--bg);width:100%;color:var(--text);text-align:left;border-radius:10px;grid-template-columns:auto 1fr auto;align-items:center;gap:14px;padding:12px 14px 12px 10px;transition:border-color .16s,box-shadow .16s,transform .16s;display:grid}.path-step:hover{border-color:var(--topic-ink);box-shadow:0 8px 22px color-mix(in srgb, var(--topic-accent), transparent 78%);transform:translate(3px)}.path-step:focus-visible{outline:3px solid var(--focus);outline-offset:2px}.path-step-num{border:1.5px solid var(--topic-ink);width:30px;height:30px;color:var(--topic-ink);font-variant-numeric:tabular-nums;border-radius:50%;place-items:center;font-size:.9rem;font-weight:700;display:grid}.path-step-body{gap:3px;min-width:0;display:grid}.path-step-title{align-items:baseline;gap:10px;font-size:1.02rem;font-weight:650;display:flex}.path-step-meta{color:var(--muted);font-variant-numeric:tabular-nums;font-size:.78rem;font-weight:500}.path-step-note{color:var(--muted);font-size:.85rem;line-height:1.45}.path-step-go{color:var(--topic-ink);font-size:1.1rem;transition:transform .16s}.path-step:hover .path-step-go{transform:translate(3px)}.fill-card{border:1px solid var(--line);background:var(--code);border-radius:12px;overflow:hidden}.fill-card-head{border-bottom:1px solid color-mix(in srgb, var(--line), transparent 30%);background:color-mix(in srgb, var(--track-accent,#15b77f), transparent 92%);color:var(--muted);letter-spacing:.04em;text-transform:uppercase;justify-content:space-between;align-items:center;padding:8px 16px;font-size:.78rem;font-weight:600;display:flex}.fill-progress{font-variant-numeric:tabular-nums;color:color-mix(in srgb, var(--track-accent,#15b77f), var(--ink-mix-color) var(--ink-mix-amount))}.fill-snippet{background:0 0;border:0;border-radius:0;margin:0;padding:18px 16px;line-height:2.1;overflow-x:auto}.fill-blank{box-sizing:content-box;border:1.5px dashed color-mix(in srgb, var(--track-accent,#15b77f), var(--line) 35%);background:color-mix(in srgb, var(--track-accent,#15b77f), transparent 90%);min-width:6ch;color:inherit;font:inherit;text-align:center;caret-color:var(--track-accent,#15b77f);border-radius:7px;margin:0 2px;padding:1px 8px;transition:border-color .14s,background .14s,box-shadow .14s;display:inline-block}.fill-blank::placeholder{color:color-mix(in srgb, var(--muted), transparent 35%);font-size:.85em}.fill-blank:focus{border-style:solid;border-color:var(--track-accent,#15b77f);box-shadow:0 0 0 3px color-mix(in srgb, var(--track-accent,#15b77f), transparent 78%);background:color-mix(in srgb, var(--track-accent,#15b77f), transparent 85%);outline:none}.fill-blank.filled{border-style:solid;border-color:color-mix(in srgb, var(--track-accent,#15b77f), var(--line) 25%);background:color-mix(in srgb, var(--track-accent,#15b77f), transparent 86%)}.sample-queries{flex-wrap:wrap;gap:6px;display:flex}.sql-playground-result{overflow:auto}.schema-panel{border:1px solid var(--line);background:var(--panel);border-radius:10px;padding:10px 14px}.schema-panel summary{cursor:pointer;color:var(--muted);font-size:.9rem;font-weight:650}.schema-tables{gap:6px;max-height:280px;margin-top:10px;display:grid;overflow-y:auto}.schema-table{text-align:left;border:1px solid var(--line);background:var(--bg);color:var(--text);border-radius:8px;gap:2px;padding:8px 10px;font-size:.84rem;display:grid}.schema-table:hover{border-color:var(--track-accent,#15b77f)}.schema-table span{color:var(--muted);font-family:var(--font-mono,monospace);font-size:.78rem}.playground-preview{min-height:120px}.reference-shell{max-width:1480px}.reference-toolbar{justify-content:space-between;align-items:end;gap:18px;margin:0 0 22px;display:flex}.reference-search{flex:1;max-width:420px}.reference-count{color:var(--muted);white-space:nowrap;font-size:.9rem;font-weight:600}.reference-set-title{font-family:var(--font-display);margin:34px 0 14px;font-size:1.4rem}.reference-grid{grid-template-columns:repeat(auto-fill,minmax(330px,1fr));gap:16px;display:grid}.reference-card{border:1px solid var(--line);border-left:4px solid var(--track-accent,var(--accent));background:var(--panel);border-radius:12px;align-content:start;gap:10px;padding:16px 18px;display:grid}.reference-card h3{margin:0;font-size:1.02rem}.reference-card ul{color:var(--muted);gap:4px;margin:0;padding-left:18px;font-size:.88rem;line-height:1.5;display:grid}.reference-example{position:relative}.reference-example pre{border:1px solid var(--line);background:var(--code);color:var(--code-text);border-radius:8px;margin:0;padding:12px 14px;font-size:.82rem;line-height:1.55;overflow-x:auto}.copy-button{border:1px solid color-mix(in srgb, var(--code-text), transparent 70%);background:color-mix(in srgb, var(--code), transparent 10%);color:var(--code-text);opacity:0;border-radius:6px;padding:3px 10px;font-size:.72rem;font-weight:700;transition:opacity .14s;position:absolute;top:8px;right:8px}.reference-example:hover .copy-button,.copy-button:focus-visible{opacity:1}.placement-trigger{color:color-mix(in srgb, var(--accent), var(--ink-mix-color) var(--ink-mix-amount));text-underline-offset:3px;background:0 0;border:0;justify-self:start;padding:0;font-size:.85rem;font-weight:700;text-decoration:underline}.placement-overlay{z-index:60;background:color-mix(in srgb, var(--bg), transparent 20%);-webkit-backdrop-filter:blur(6px);backdrop-filter:blur(6px);place-items:center;padding:20px;display:grid;position:fixed;inset:0}.placement-card{border:1px solid var(--line);background:var(--panel);width:min(640px,100%);max-height:90vh;box-shadow:0 30px 80px var(--shadow);border-radius:16px;gap:16px;padding:26px 28px;animation:.36s cubic-bezier(.2,.7,.2,1) both card-rise;display:grid;overflow-y:auto}.placement-head{justify-content:space-between;align-items:start;gap:16px;display:flex}.placement-head h2{font-family:var(--font-display);margin:6px 0 0;font-size:1.5rem}.placement-progress{align-items:center;gap:7px;display:flex}.placement-dot{border:1.5px solid var(--line);background:0 0;border-radius:50%;width:11px;height:11px}.placement-dot.cleared{border-color:var(--accent);background:var(--accent)}.placement-dot.current{border-color:var(--accent);box-shadow:0 0 0 3px color-mix(in srgb, var(--accent), transparent 75%)}.placement-counter{color:var(--muted);margin-left:8px;font-size:.8rem;font-weight:600}.placement-prompt{margin:0;font-size:1.06rem;font-weight:600;line-height:1.5}.placement-snippet{border:1px solid var(--line);background:var(--code);color:var(--code-text);border-radius:8px;margin:0;padding:12px 14px;font-size:.88rem;overflow-x:auto}.choice.placement-right{border-color:var(--accent);background:color-mix(in srgb, var(--accent), transparent 88%)}.choice.placement-wrong{border-color:var(--danger);background:color-mix(in srgb, var(--danger), transparent 90%)}.placement-hint{color:var(--muted);margin:0;font-size:.84rem}.placement-result{gap:12px;display:grid}.placement-verdict{margin:0;font-size:1.15rem;line-height:1.5}.placement-reason,.placement-cleared{color:var(--muted);margin:0;line-height:1.55}.placement-actions{flex-wrap:wrap;gap:10px;margin-top:6px;display:flex}.prompt-blank{border:1.5px dashed color-mix(in srgb, var(--track-accent,var(--accent)), var(--line) 35%);background:color-mix(in srgb, var(--track-accent,var(--accent)), transparent 90%);min-width:2.4em;color:color-mix(in srgb, var(--track-accent,var(--accent)), var(--ink-mix-color) var(--ink-mix-amount));font-family:var(--font-body);vertical-align:.18em;letter-spacing:0;border-radius:8px;justify-content:center;align-items:center;margin:0 .12em;padding:0 .45em;font-size:.55em;font-weight:700;display:inline-flex}
