:root{--bg: #12151c;--bg-raise: #161a22;--panel: #1a1e28;--panel-2: #212633;--line: #2b303d;--line-soft: #232834;--text: #dde3ed;--muted: #949eb0;--faint: #6b7689;--shell: #5fc39a;--cpp: #85a8d8;--amrex: #cf9a72;--accent: var(--amrex);--accent-soft: color-mix(in srgb, var(--accent) 12%, transparent);--accent-line: color-mix(in srgb, var(--accent) 34%, transparent);--ok: #5fc39a;--warn: #d3b578;--bad: #d68a95;--term-bg: #10131a;--code-bg: #15181f;--radius: 14px;--radius-sm: 9px;--sans: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", Roboto, Helvetica, Arial, sans-serif;--mono: ui-monospace, "SF Mono", SFMono-Regular, Menlo, Consolas, monospace;color-scheme:dark}*{box-sizing:border-box}html,body{margin:0;padding:0;background:var(--bg);color:var(--text);font-family:var(--sans);font-size:16px;line-height:1.6;-webkit-font-smoothing:antialiased}::selection{background:color-mix(in srgb,var(--accent) 35%,transparent)}a{color:inherit}button{font-family:inherit;font-size:inherit;cursor:pointer;border:none;background:none;color:inherit}:where(a,button,input,textarea,summary,[tabindex]):focus-visible{outline:3px solid color-mix(in srgb,var(--accent) 74%,white);outline-offset:3px}.t-shell{--accent: var(--shell)}.t-cpp{--accent: var(--cpp)}.t-amrex{--accent: var(--amrex)}.topbar{position:sticky;top:0;z-index:50;display:flex;align-items:center;gap:24px;padding:0 28px;height:58px;background:var(--bg);border-bottom:1px solid var(--line-soft)}.topbar .brand{display:flex;align-items:center;gap:10px;font-weight:700;letter-spacing:-.01em;font-size:16px;text-decoration:none}.topbar nav{display:flex;gap:4px;margin-left:8px}.topbar nav a{text-decoration:none;color:var(--muted);font-size:14px;font-weight:500;padding:6px 12px;border-radius:8px;transition:color .15s,background .15s}.topbar nav a:hover{color:var(--text);background:var(--panel)}.topbar nav a.active{color:var(--text);background:var(--panel-2)}.topbar .spacer{flex:1}.topbar .xp{font-size:13px;color:var(--muted);font-variant-numeric:tabular-nums;display:flex;align-items:center;gap:8px}.topbar .xp b{color:var(--text)}.topbar-search,.mobile-menu-button{min-width:34px;height:34px;display:inline-flex;align-items:center;justify-content:center;gap:7px;padding:0 10px;border:1px solid var(--line);border-radius:9px;background:var(--panel);color:var(--muted);font-size:13px}.topbar-search:hover,.mobile-menu-button:hover{color:var(--text);border-color:var(--accent-line)}.mobile-menu-button{display:none;padding:0;font-size:18px}.desktop-settings{display:contents}.mobile-menu-scrim{position:fixed;top:0;right:0;bottom:0;left:0;z-index:70;background:#03070db8}.mobile-drawer{position:fixed;z-index:71;top:0;right:0;bottom:0;width:min(360px,calc(100vw - 28px));display:flex;flex-direction:column;padding:18px;overflow-y:auto;background:var(--bg-raise);border-left:1px solid var(--line);box-shadow:-22px 0 70px #00000073}.drawer-head{display:flex;align-items:center;gap:12px;font-weight:750;font-size:17px;margin-bottom:16px}.drawer-head button{margin-left:auto;width:34px;height:34px;border:1px solid var(--line);border-radius:9px;font-size:22px;color:var(--muted)}.drawer-search{display:flex;align-items:center;gap:9px;width:100%;padding:11px 12px;margin-bottom:16px;border:1px solid var(--line);border-radius:10px;background:var(--panel);color:var(--muted);text-align:left}.mobile-drawer nav{display:flex;flex-direction:column;gap:4px}.mobile-drawer nav a{display:flex;align-items:center;gap:10px;padding:10px 11px;border-radius:9px;text-decoration:none;color:var(--muted);font-size:14.5px;font-weight:550}.mobile-drawer nav a:hover,.mobile-drawer nav a[aria-current=page]{color:var(--text);background:var(--panel)}.drawer-dot{width:8px;height:8px;border-radius:50%;background:var(--accent)}.drawer-count{margin-left:auto;min-width:22px;padding:1px 7px;border-radius:99px;background:var(--accent);color:#0a0e16;text-align:center;font-size:11px}.drawer-foot{margin-top:auto;padding-top:18px;border-top:1px solid var(--line)}.drawer-foot p{margin:0 0 10px;color:var(--muted);font-size:12.5px}.drawer-foot p b{color:var(--text)}.page{max-width:1080px;margin:0 auto;padding:40px 28px 120px}.footer{border-top:1px solid var(--line-soft);color:var(--faint);font-size:13px;padding:28px;text-align:center}.footer a{color:var(--muted)}.pwa-update{position:fixed;z-index:90;right:18px;bottom:18px;max-width:440px;display:flex;align-items:center;gap:9px;padding:13px;border:1px solid var(--accent-line);border-radius:var(--radius);background:var(--panel);box-shadow:0 18px 50px #00000073}.pwa-update>div{display:flex;flex-direction:column;margin-right:6px}.pwa-update b{font-size:13.5px}.pwa-update span{color:var(--muted);font-size:11.5px}.pwa-update .btn{white-space:nowrap}@media(max-width:620px){.pwa-update{left:10px;right:10px;bottom:10px;flex-wrap:wrap}.pwa-update>div{flex:1 1 100%}}.skip-link{position:fixed;z-index:120;left:14px;top:10px;transform:translateY(-150%);padding:8px 12px;border-radius:8px;background:var(--text);color:var(--bg);text-decoration:none;font-weight:700}.skip-link:focus{transform:translateY(0)}.route-state,.route-error,.not-found{margin:60px auto;max-width:640px;padding:26px;border:1px solid var(--line);border-radius:var(--radius);background:var(--panel)}.route-state{min-height:68vh}.route-state{display:flex;align-items:center;justify-content:center;gap:12px;color:var(--muted)}.route-spinner,.global-search-spinner{width:18px;height:18px;border:2px solid var(--line);border-top-color:var(--accent);border-radius:50%;animation:spin .8s linear infinite}.route-error p,.not-found p{color:var(--muted)}.not-found h1{margin:6px 0}@keyframes spin{to{transform:rotate(360deg)}}.global-search-layer{position:fixed;top:0;right:0;bottom:0;left:0;z-index:100;display:grid;place-items:start center;padding:min(9vh,72px) 16px 16px}.global-search-scrim{position:absolute;top:0;right:0;bottom:0;left:0;width:100%;height:100%;background:#03060bc7}.global-search-dialog{position:relative;width:min(760px,100%);max-height:min(790px,84vh);display:flex;flex-direction:column;overflow:hidden;border:1px solid var(--line);border-radius:18px;background:var(--bg-raise);box-shadow:0 28px 90px #0009}.global-search-head{display:flex;align-items:flex-start;gap:18px;padding:20px 22px 0}.global-search-eyebrow{color:var(--faint);font-size:12px;letter-spacing:.02em;font-weight:600}.global-search-head h2{margin:1px 0 0;font-size:21px}.global-search-close{margin-left:auto;width:34px;height:34px;display:grid;place-items:center;border:1px solid var(--line);border-radius:9px;color:var(--muted);font-size:22px}.global-search-help{margin:4px 22px 13px;color:var(--muted);font-size:12.5px}.global-search-field{display:flex;align-items:center;gap:9px;margin:0 22px;padding:0 12px;border:1px solid var(--line);border-radius:11px;background:var(--panel)}.global-search-field:focus-within{border-color:var(--accent-line);box-shadow:0 0 0 3px var(--accent-soft)}.global-search-field input{flex:1;min-width:0;padding:12px 0;border:0;outline:0;background:transparent;color:var(--text);font:inherit}.global-search-icon{color:var(--muted);font-size:19px}.global-search-clear{color:var(--muted);font-size:12.5px}.global-search-status{min-height:24px;padding:5px 22px 0;color:var(--faint);font-size:11.5px}.global-search-body{min-height:220px;overflow-y:auto;padding:0 12px 12px}.global-search-state{min-height:220px;display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;color:var(--muted)}.global-search-state b{color:var(--text)}.global-search-state p{max-width:430px;margin:4px 0 0;font-size:13px}.global-search-retry{margin-top:14px;padding:7px 12px;border:1px solid var(--line);border-radius:8px}.global-search-results{list-style:none;margin:0;padding:0;display:flex;flex-direction:column;gap:6px}.global-search-result{display:grid;grid-template-columns:auto minmax(0,1fr) auto;gap:12px;align-items:start;padding:12px;border:1px solid transparent;border-radius:10px;text-decoration:none}.global-search-result:hover,.global-search-result:focus-visible{border-color:var(--accent-line);background:var(--panel)}.global-search-kind{margin-top:2px;padding:2px 7px;border:1px solid var(--line);border-radius:99px;color:var(--muted);font-size:10px}.global-search-kind.kind-glossary{color:var(--shell)}.global-search-kind.kind-exercise{color:var(--amrex)}.global-search-kind.kind-lesson{color:var(--cpp)}.global-search-result-copy{display:flex;flex-direction:column;min-width:0}.global-search-result-copy b{font-size:14.5px}.global-search-result-copy>span{color:var(--muted);font-size:12.5px;line-height:1.4}.global-search-result-copy small{margin-top:3px;color:var(--faint);font-size:10.5px}.global-search-arrow{color:var(--faint)}.global-search-foot{display:flex;gap:18px;padding:9px 22px;border-top:1px solid var(--line);color:var(--faint);font-size:10.5px}.global-search-foot span{display:flex;align-items:center;gap:4px}.global-search-foot kbd{padding:1px 5px;border:1px solid var(--line);border-radius:4px;background:var(--panel);color:var(--muted);font-family:var(--mono)}@media(max-width:520px){.global-search-layer{padding:8px}.global-search-dialog{max-height:calc(100dvh - 16px);border-radius:14px}.global-search-head{padding:15px 15px 0}.global-search-help{margin:3px 15px 11px}.global-search-field{margin:0 15px}.global-search-status{padding-left:15px}.global-search-result{grid-template-columns:minmax(0,1fr) auto}.global-search-kind{grid-column:1 / -1;justify-self:start}.global-search-foot{display:none}}.hero{position:relative;padding:72px 0 56px;text-align:center;overflow:hidden}.hero .mesh{position:absolute;top:-40px;right:0;bottom:0;left:0;opacity:.3;pointer-events:none}.hero .mesh:after{content:"";position:absolute;top:0;right:0;bottom:0;left:0;background:radial-gradient(ellipse 70% 90% at 50% 0%,transparent 30%,var(--bg) 75%)}.hero h1{position:relative;font-size:clamp(38px,6vw,58px);letter-spacing:-.03em;line-height:1.06;margin:18px 0 14px;font-weight:800}.hero h1 .grad{color:var(--muted)}.hero p.sub{position:relative;color:var(--muted);font-size:18px;max-width:560px;margin:0 auto}.hero .badge{position:relative;display:inline-flex;align-items:center;gap:8px;font-size:13px;font-weight:600;color:var(--muted);border:1px solid var(--line);border-radius:999px;padding:5px 14px;background:var(--panel)}.tracks-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(280px,1fr));gap:18px;margin-top:34px}.track-card{position:relative;display:flex;flex-direction:column;gap:10px;text-align:left;text-decoration:none;background:var(--panel);border:1px solid var(--line);border-radius:var(--radius);padding:24px;transition:border-color .18s ease}.track-card:hover{border-color:var(--accent-line)}.track-card .track-num{font-family:var(--mono);font-size:12px;color:var(--faint);letter-spacing:.06em;font-weight:600}.track-card h3{margin:0;font-size:21px;letter-spacing:-.01em}.track-card p{margin:0;color:var(--muted);font-size:14.5px;flex:1}.track-card .card-foot{display:flex;align-items:center;justify-content:space-between;margin-top:10px;font-size:13px;color:var(--faint)}.ring{width:40px;height:40px}.ring .bg{stroke:var(--line)}.ring .fg{stroke:var(--accent);transition:stroke-dashoffset .4s ease}.ring text{fill:var(--muted);font-size:10.5px;font-family:var(--sans);font-weight:600}.continue-strip{display:flex;align-items:center;gap:14px;margin:26px 0 0;padding:14px 18px;background:var(--panel);border:1px solid var(--accent-line);border-radius:var(--radius);text-decoration:none;transition:background .15s}.continue-strip:hover{background:var(--panel-2)}.continue-strip .go{margin-left:auto;color:var(--accent);font-weight:600;font-size:14px;white-space:nowrap}.continue-strip .what{font-size:14.5px}.continue-strip .what b{display:block;font-size:15px}.continue-strip .what span{color:var(--muted);font-size:13px}.home-section-title{margin:56px 0 6px;font-size:13.5px;letter-spacing:.02em;color:var(--faint);font-weight:650}.how-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:16px;margin-top:16px}.how-card{background:var(--panel);border:1px solid var(--line-soft);border-radius:var(--radius);padding:20px}.how-card h4{margin:0 0 6px;font-size:15.5px}.how-card p{margin:0;color:var(--muted);font-size:14px}.how-card .ico{font-size:20px;margin-bottom:10px}.today-hero{padding-bottom:38px}.today-grid{display:grid;grid-template-columns:minmax(0,1.65fr) minmax(260px,.75fr);gap:18px}.today-primary,.today-card,.home-path-preview,.path-phase,.progress-transfer{border:1px solid var(--line);border-radius:var(--radius);background:var(--panel)}.today-primary{padding:26px}.today-primary .eyebrow,.home-path-preview .eyebrow,.progress-transfer .eyebrow{color:var(--faint);font-size:12.5px;letter-spacing:.02em;font-weight:650}.today-primary h2{margin:3px 0 6px;font-size:27px;letter-spacing:-.02em}.today-primary>p:not(.today-phase){color:var(--muted);margin:0;max-width:640px}.today-phase{margin:10px 0 0;color:var(--muted);font-size:13px;font-weight:600}.today-actions{display:flex;flex-wrap:wrap;gap:9px;margin-top:22px}.today-actions .btn{text-decoration:none}.today-progress{display:grid;grid-template-columns:1fr auto;gap:7px 14px;margin-top:26px;padding-top:18px;border-top:1px solid var(--line-soft);color:var(--muted);font-size:12.5px}.today-progress span:last-of-type{font-variant-numeric:tabular-nums}.today-progress i{grid-column:1 / -1;height:6px;border-radius:99px;background:var(--line);overflow:hidden}.today-progress i b{display:block;height:100%;border-radius:inherit;background:var(--accent)}.today-side{display:grid;gap:18px}.today-card{display:flex;flex-direction:column;padding:20px;text-decoration:none;transition:border-color .15s,background .15s}.today-card:hover{border-color:var(--accent-line);background:var(--panel-2)}.today-card .eyebrow{color:var(--faint);font-size:12px;letter-spacing:.02em;font-weight:650}.today-card strong{margin:6px 0 5px;font-size:17px}.today-card>span:last-child{color:var(--muted);font-size:13px;line-height:1.5}.home-path-preview{margin-top:38px;padding:24px}.home-path-preview h2{margin:5px 0 2px;font-size:23px}.home-path-preview>div:first-child>p{margin:0;color:var(--muted);font-size:14px}.phase-strip{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:10px;margin-top:20px}.phase-strip a{display:flex;flex-direction:column;min-width:0;padding:14px;border:1px solid var(--line-soft);border-radius:10px;text-decoration:none;background:var(--bg-raise)}.phase-strip a:hover{border-color:var(--accent-line)}.phase-strip a>span{color:var(--faint);font-family:var(--mono);font-size:11px}.phase-strip a b{margin:5px 0;font-size:13.5px;line-height:1.35}.phase-strip a small{color:var(--faint);font-size:11.5px;line-height:1.4}.path-summary{display:flex;align-items:center;gap:15px;max-width:620px;color:var(--muted);font-size:13px}.path-summary .track-progress{flex:1}.path-phases{display:flex;flex-direction:column;gap:24px;margin-top:30px}.path-phase{padding:22px;scroll-margin-top:76px}.path-phase.highlighted{border-color:var(--accent-line);box-shadow:0 0 0 3px var(--accent-soft)}.path-phase-head{display:grid;grid-template-columns:auto minmax(0,1fr) auto;gap:14px;align-items:start}.path-phase-num{color:var(--faint);font-family:var(--mono);font-size:11.5px;letter-spacing:.04em;padding-top:5px}.path-phase-head h2{margin:0;font-size:21px}.path-phase-head p{margin:3px 0 0;color:var(--muted);font-size:13.5px}.path-phase-toggle{display:inline-flex;align-items:center;gap:8px;padding:4px 10px;border-radius:99px;border:1px solid var(--line);color:var(--muted);font-size:12px}.path-phase-toggle:hover{color:var(--text);border-color:var(--accent-line)}.path-phase.open .path-phase-toggle{color:var(--accent);border-color:var(--accent-line)}.path-items{display:flex;flex-direction:column;gap:7px;margin-top:18px}.path-item{display:grid;grid-template-columns:30px minmax(0,1fr) auto;gap:13px;align-items:center;padding:13px;border:1px solid var(--line-soft);border-radius:10px;background:var(--bg-raise);text-decoration:none}.path-item:hover{border-color:var(--accent-line)}.path-item-state{width:28px;height:28px;display:grid;place-items:center;border:1px solid var(--line);border-radius:50%;color:var(--faint);font-size:12px}.path-item.done .path-item-state{color:var(--accent);border-color:var(--accent);background:var(--accent-soft)}.path-item-copy{display:flex;flex-direction:column;min-width:0}.path-item-copy b{font-size:14.5px}.path-item-copy small{margin-top:1px;color:var(--muted);font-size:12.5px;line-height:1.45}.path-item-copy em{margin-top:5px;color:var(--warn);font-size:11.5px;font-style:normal}.path-item-meta{display:flex;gap:7px}.path-item-meta span{padding:2px 7px;border:1px solid var(--line);border-radius:99px;color:var(--muted);font-size:10.5px;white-space:nowrap}.milestone-card{margin-top:15px;padding:17px;border-left:3px solid var(--accent);border-radius:9px;background:color-mix(in srgb,var(--accent) 6%,var(--bg-raise))}.milestone-card .eyebrow{color:var(--faint);font-size:12px;letter-spacing:.02em;font-weight:650}.milestone-card h3{margin:3px 0 2px;font-size:16px}.milestone-card p,.milestone-card li{color:var(--muted);font-size:12.5px}.milestone-card p{margin:0}.milestone-card ul{margin:9px 0 0;padding-left:19px}.progress-transfer{display:grid;grid-template-columns:minmax(0,1fr) auto;gap:20px;margin-top:34px;padding:22px}.progress-transfer h2{margin:4px 0 2px;font-size:19px}.progress-transfer>div:first-child p{margin:0;color:var(--muted);font-size:13.5px}.progress-transfer-actions{display:flex;align-items:center;flex-wrap:wrap;gap:8px}.progress-file-label{display:inline-flex;align-items:center;cursor:pointer}.progress-import-confirm{grid-column:1 / -1;display:flex;align-items:center;flex-wrap:wrap;gap:8px;padding-top:14px;border-top:1px solid var(--line)}.progress-import-confirm p{margin:0 auto 0 0;color:var(--muted);font-size:13px}.progress-transfer-message{grid-column:1 / -1;margin:0;color:var(--ok);font-size:13px}.sr-only{position:absolute!important;width:1px!important;height:1px!important;padding:0!important;margin:-1px!important;overflow:hidden!important;clip:rect(0,0,0,0)!important;white-space:nowrap!important;border:0!important}.library-grid{margin-bottom:8px}@media(max-width:820px){.today-grid{grid-template-columns:1fr}.today-side,.phase-strip{grid-template-columns:1fr 1fr}}@media(max-width:600px){.today-hero{padding-top:46px}.today-side,.phase-strip{grid-template-columns:1fr}.path-phase{padding:16px}.path-phase-head{grid-template-columns:1fr auto}.path-phase-num{grid-column:1 / -1}.path-item{grid-template-columns:28px minmax(0,1fr)}.path-item-meta{grid-column:2}.progress-transfer{grid-template-columns:1fr}}.track-hero{padding:26px 0 8px}.track-hero .eyebrow{font-size:13px;color:var(--faint);letter-spacing:.02em;font-weight:600}.track-hero h1{margin:8px 0;font-size:34px;letter-spacing:-.02em}.track-hero p{color:var(--muted);max-width:640px;margin:0 0 18px}.track-progress{height:6px;background:var(--line-soft);border-radius:99px;overflow:hidden;max-width:380px}.track-progress i{display:block;height:100%;background:var(--accent);border-radius:99px;transition:width .4s ease}.unit{margin-top:40px}.unit-head{display:flex;align-items:baseline;gap:12px;margin-bottom:4px}.unit-head .unit-num{font-family:var(--mono);color:var(--faint);font-size:13px;font-weight:600}.unit-head h2{margin:0;font-size:21px;letter-spacing:-.01em}.unit>p.blurb{color:var(--muted);font-size:14.5px;margin:2px 0 14px;max-width:640px}.lesson-list{display:flex;flex-direction:column;gap:8px}.lesson-row{display:flex;align-items:center;gap:14px;padding:13px 16px;background:var(--panel);border:1px solid var(--line-soft);border-radius:var(--radius-sm);text-decoration:none;transition:border-color .15s,background .15s}.lesson-row:hover{border-color:var(--accent-line);background:var(--panel-2)}.lesson-row .status{width:26px;height:26px;border-radius:50%;border:1.5px solid var(--line);display:grid;place-items:center;font-size:13px;color:var(--faint);flex-shrink:0;font-variant-numeric:tabular-nums}.lesson-row .status.done{background:var(--accent-soft);border-color:var(--accent);color:var(--accent);font-weight:700}.lesson-row .l-title{font-size:15px;font-weight:550}.lesson-row .l-sub{color:var(--faint);font-size:12.5px;margin-top:1px}.catalog-core{color:var(--accent)}.catalog-optional{color:var(--faint)}.lesson-row .meta{margin-left:auto;display:flex;gap:8px;align-items:center}.pill{font-size:11.5px;font-weight:600;color:var(--muted);background:var(--bg-raise);border:1px solid var(--line-soft);padding:2.5px 9px;border-radius:999px;white-space:nowrap}.pill.lvl-Beginner{color:#8fc6ab}.pill.lvl-Intermediate{color:#cdb384}.pill.lvl-Advanced{color:#cf9ba5}.project-row{border-style:dashed;border-color:var(--accent-line)}.project-row .status{border-radius:8px}.lesson-col{max-width:820px}.lesson-topbar{display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:10px 18px;margin-bottom:26px}.lesson-topbar .crumbs{margin-bottom:0}.lesson-topbar .mode-toggle{margin:0}.crumbs{display:flex;gap:8px;align-items:center;font-size:13.5px;color:var(--faint);margin-bottom:22px}.crumbs a{color:var(--muted);text-decoration:none}.crumbs a:hover{color:var(--text)}.crumbs .sep{opacity:.5}.lesson-head h1{font-size:30px;letter-spacing:-.02em;margin:0 0 8px}.lesson-head .meta-row{display:flex;gap:8px;margin-bottom:30px}.lesson-meta{margin:0 0 32px;color:var(--faint);font-size:13.5px}.lesson-body{max-width:720px}.lesson-body p{color:#c9d3e3;font-size:16px;margin:14px 0}.lesson-body p code,.lesson-body li code,.note code,.ex-instructions code,.quiz-q code,td code,th code,.step-md code{font-family:var(--mono);font-size:.88em;background:var(--code-bg);border:1px solid var(--line-soft);padding:1.5px 6px;border-radius:6px;color:#d3b795;white-space:nowrap}.t-shell .lesson-body code,.t-shell .note code,.t-shell .ex-instructions code,.t-shell .quiz-q code,.t-shell td code,.t-shell .step-md code{color:#a5cdba}.t-cpp .lesson-body code,.t-cpp .note code,.t-cpp .ex-instructions code,.t-cpp .quiz-q code,.t-cpp td code,.t-cpp .step-md code{color:#b0c4e2}.lesson-body h2{font-size:21px;letter-spacing:-.01em;margin:40px 0 4px;padding-top:8px}.lesson-body h2:before{content:"";display:block;width:26px;height:3px;border-radius:2px;background:var(--accent);margin-bottom:12px}.lesson-body ul{color:#c9d3e3;padding-left:22px;margin:12px 0}.lesson-body li{margin:6px 0}.note{display:flex;gap:12px;margin:18px 0;padding:14px 16px;border-radius:var(--radius-sm);font-size:14.5px;border:1px solid var(--line);background:var(--panel);color:#c9d3e3}.note .n-ico{flex-shrink:0}.note.tip{border-color:color-mix(in srgb,var(--ok) 35%,transparent);background:color-mix(in srgb,var(--ok) 6%,var(--panel))}.note.warn{border-color:color-mix(in srgb,var(--warn) 35%,transparent);background:color-mix(in srgb,var(--warn) 5%,var(--panel))}.note.info{border-color:color-mix(in srgb,var(--cpp) 30%,transparent);background:color-mix(in srgb,var(--cpp) 5%,var(--panel))}table.tbl{width:100%;border-collapse:collapse;margin:16px 0;font-size:14px;border:1px solid var(--line);border-radius:var(--radius-sm);overflow:hidden}table.tbl th{text-align:left;padding:9px 14px;background:var(--panel-2);color:var(--muted);font-weight:600;font-size:13px;letter-spacing:.01em}table.tbl td{padding:9px 14px;border-top:1px solid var(--line-soft);color:#c9d3e3}.codeblock{margin:18px 0;border:1px solid var(--line);border-radius:var(--radius-sm);overflow:hidden;background:var(--code-bg)}.codeblock .cb-head{display:flex;align-items:center;gap:10px;padding:7px 14px;background:var(--panel);border-bottom:1px solid var(--line-soft);font-size:12px;color:var(--faint);font-family:var(--mono)}.codeblock .cb-head .dot{width:9px;height:9px;border-radius:50%;background:var(--line)}.codeblock .cb-head .dot.a{background:color-mix(in srgb,var(--accent) 70%,transparent)}.codeblock pre{margin:0;padding:15px 17px;overflow-x:auto;font-family:var(--mono);font-size:13.3px;line-height:1.62;color:#dde5f1}.tok-kw{color:#b3a0d4}.tok-str{color:#9dcbac}.tok-num{color:#d4b28b}.tok-cmt{color:#66718a;font-style:italic}.tok-fn{color:#8fb0da}.tok-pre{color:#cf99a3}.tok-type{color:#8dc3be}.tok-prompt{color:var(--ok);font-weight:600}.tok-out{color:#93a0b4}.ex-divider{display:flex;align-items:center;gap:14px;margin:52px 0 20px;color:var(--faint);font-size:13.5px;font-weight:650;letter-spacing:.02em}.ex-divider:after{content:"";flex:1;height:1px;background:var(--line)}.ex-card{border:1px solid var(--line);border-radius:var(--radius);background:var(--panel);margin:26px 0;overflow:hidden}.ex-card.done{border-color:color-mix(in srgb,var(--ok) 45%,transparent)}.ex-head{display:flex;align-items:center;gap:12px;padding:16px 18px 2px}.ex-head .ex-kind{font-size:11.5px;letter-spacing:.02em;color:var(--muted);border:1px solid var(--line);background:var(--panel-2);border-radius:6px;padding:3px 9px;font-weight:600}.ex-head h3{margin:0;font-size:16px;flex:1}.ex-head .ex-check{color:var(--ok);font-weight:700;font-size:14px;display:flex;gap:6px;align-items:center}.ex-instructions{padding:14px 18px 4px;font-size:14.5px;color:#c9d3e3}.ex-instructions p{margin:0 0 10px}.ex-instructions ol,.ex-instructions ul{margin:4px 0 10px;padding-left:22px}.ex-instructions li{margin:4px 0}.ex-actions{display:flex;gap:10px;align-items:center;padding:12px 18px 16px;flex-wrap:wrap}.btn{font-size:13.5px;font-weight:600;padding:8px 16px;border-radius:9px;border:1px solid var(--line);background:var(--panel-2);color:var(--text);transition:border-color .15s,background .15s,transform .05s}.btn:hover{border-color:var(--accent-line)}.btn:active{transform:translateY(1px)}.btn.primary{background:var(--accent);color:#08110c;border-color:transparent}.btn.primary:hover{background:color-mix(in srgb,var(--accent) 90%,white)}.btn.ghost{background:transparent;color:var(--muted)}.btn.ghost:hover{color:var(--text)}.hint-box,.solution-box{margin:0 18px 14px;padding:12px 15px;border-radius:var(--radius-sm);font-size:14px;border:1px dashed var(--line);background:var(--bg-raise);color:#c9d3e3}.solution-box pre{margin:8px 0 0;font-family:var(--mono);font-size:13px;white-space:pre-wrap;color:#dde5f1}.check-cap{margin:2px 18px 0;font-size:12px;color:var(--muted);opacity:.85}.check-list{list-style:none;margin:0;padding:4px 18px 8px;display:flex;flex-direction:column;gap:6px}.check-list li{display:flex;gap:10px;align-items:baseline;font-size:13.5px;color:var(--muted)}.check-list li .mark{font-weight:700;width:16px;flex-shrink:0;text-align:center}.check-list li.pass{color:#9bc9b1}.check-list li.pass .mark{color:var(--ok)}.check-list li.fail .mark{color:var(--bad)}.pass-banner{margin:0 18px 16px;padding:11px 15px;border-radius:var(--radius-sm);background:color-mix(in srgb,var(--ok) 10%,transparent);border:1px solid color-mix(in srgb,var(--ok) 40%,transparent);color:#9bc9b1;font-size:14px;font-weight:600}.pass-honest{display:block;margin-top:6px;font-weight:400;font-size:12.5px;opacity:.82}.machine-loop{margin:4px 18px 16px;padding:13px 15px;border-radius:var(--radius-sm);border:1px solid var(--line);background:var(--bg-raise)}.ml-head{font-weight:700;font-size:14px;letter-spacing:.01em;color:var(--text)}.ml-lead{margin:5px 0 10px;font-size:12.8px;color:var(--muted);line-height:1.5}.ml-lead code,.ml-steps code{font-family:var(--mono);font-size:.92em;color:var(--text);background:var(--code-bg);padding:1px 5px;border-radius:5px}.ml-steps{margin:0 0 12px;padding-left:20px;display:flex;flex-direction:column;gap:4px;font-size:12.8px;color:#c9d3e3;line-height:1.5}.ml-cmd{padding:9px 12px;border-radius:8px;overflow-x:auto;background:var(--code-bg);border:1px solid var(--line)}.ml-cmd code{font-family:var(--mono);font-size:12.5px;white-space:pre;color:#bfcde2}.ml-actions{display:flex;gap:8px;flex-wrap:wrap;margin-top:10px}.copy-btn{font-size:12.5px}.ml-verify{margin-top:12px}.ml-verify label{display:block;font-size:12.5px;color:var(--muted);margin-bottom:5px}.ml-verify textarea{width:100%;box-sizing:border-box;resize:vertical;min-height:62px;font-family:var(--mono);font-size:12.5px;padding:8px 10px;border-radius:8px;border:1px solid var(--line);background:var(--term-bg);color:var(--text)}.ml-noreason{margin:10px 0 0;font-size:12.8px;color:var(--muted);line-height:1.5}.hint-title{font-weight:650;font-size:13.5px;color:var(--text);margin-bottom:4px}.hint-box .hint-prose{font-size:13.5px}.hint-box .hint-prose p{margin:4px 0}.hint-code,.solution-box pre.lang-cpp,.solution-box pre.lang-bash{margin:8px 0 0;padding:10px 12px;border-radius:8px;background:var(--code-bg);border:1px solid var(--line);font-family:var(--mono);font-size:12.5px;white-space:pre-wrap;color:#dde5f1;overflow-x:auto}.sol-note{margin-top:9px;font-size:12.5px;color:var(--warn);opacity:.92}.check-list li .check-body{display:flex;flex-direction:column;gap:3px}.check-list li.fail .check-why{font-size:12.5px;color:var(--muted);line-height:1.45;border-left:2px solid color-mix(in srgb,var(--bad) 45%,transparent);padding-left:9px}.check-list li.fail .check-why p{margin:2px 0}.check-list li.fail .check-why code{font-family:var(--mono);font-size:.92em;color:#d3b8ab}.compiler-lab{margin:0 18px 12px;padding:13px 15px;border-radius:var(--radius-sm);border:1px solid color-mix(in srgb,var(--bad) 34%,transparent);background:color-mix(in srgb,var(--bad) 7%,transparent)}.cl-head{font-weight:650;font-size:13.5px;color:#d4a4ad}.cl-error{margin:9px 0;padding:10px 12px;border-radius:8px;background:var(--term-bg);border:1px solid var(--line);font-family:var(--mono);font-size:12px;white-space:pre-wrap;color:#cf99a3;overflow-x:auto}.cl-lead{margin:0;font-size:12.8px;color:var(--muted);line-height:1.5}.fail-note{margin:0 18px 14px;padding:10px 15px;border-radius:var(--radius-sm);background:color-mix(in srgb,var(--warn) 7%,transparent);border:1px solid color-mix(in srgb,var(--warn) 30%,transparent);color:#d3c39c;font-size:13.5px}.term{margin:4px 18px 14px;background:var(--term-bg);border:1px solid var(--line);border-radius:var(--radius-sm);overflow:hidden;font-family:var(--mono);font-size:13.2px}.term-head{display:flex;align-items:center;gap:7px;padding:8px 13px;background:var(--panel);border-bottom:1px solid var(--line-soft)}.term-head .td{width:10px;height:10px;border-radius:50%;background:var(--line)}.term-head .term-title{margin-left:8px;color:var(--faint);font-size:11.5px}.term-head .term-reset{margin-left:auto;color:var(--faint);font-size:11.5px;font-family:var(--sans);font-weight:600}.term-head .term-reset:hover{color:var(--text)}.term-scroll{padding:12px 14px;height:300px;overflow-y:auto;cursor:text;line-height:1.55}.term-scroll.tall{height:380px}.term-line{white-space:pre-wrap;word-break:break-all;color:#cfd8d3}.term-line .prompt{color:var(--ok);font-weight:600}.term-line .branch{color:#8fb0da}.term-line.term-err{color:#cf99a3}.term-line.term-dim{color:#7c8ba1}.term-input-row{display:flex;align-items:baseline}.term-input-row .prompt{color:var(--ok);font-weight:600;white-space:pre}.term-input-row .branch{color:#8fb0da}.term-input{flex:1;background:none;border:none;outline:none;color:#e8f4ee;font-family:var(--mono);font-size:13.2px;padding:0 0 0 2px;caret-color:var(--ok)}.editor{margin:4px 18px 14px;border:1px solid var(--line);border-radius:var(--radius-sm);overflow:hidden;background:var(--code-bg)}.editor-head{display:flex;align-items:center;padding:8px 14px;background:var(--panel-2);border-bottom:1px solid var(--line-soft);font-family:var(--mono);font-size:11.5px;color:var(--faint)}.editor textarea{display:block;width:100%;min-height:220px;resize:vertical;background:transparent;color:#dde5f1;border:none;outline:none;padding:14px 16px;font-family:var(--mono);font-size:13.3px;line-height:1.6;-moz-tab-size:4;tab-size:4}.quiz-q{padding:4px 18px 8px;font-size:15px;color:#dde5f1}.quiz-opts{display:flex;flex-direction:column;gap:8px;padding:4px 18px 16px}.quiz-opt{text-align:left;padding:11px 15px;border-radius:var(--radius-sm);border:1px solid var(--line);background:var(--bg-raise);font-size:14.5px;color:#c9d3e3;transition:border-color .12s,background .12s}.quiz-opt:hover:not(:disabled){border-color:var(--accent-line)}.quiz-opt.sel-right{border-color:var(--ok);background:color-mix(in srgb,var(--ok) 8%,transparent);color:#abd3bd}.quiz-opt.sel-wrong{border-color:var(--bad);background:color-mix(in srgb,var(--bad) 8%,transparent);color:#d5adb4}.quiz-opt:disabled{cursor:default;opacity:.85}.quiz-explain{margin:0 18px 16px;padding:11px 15px;font-size:13.5px;color:var(--muted);border-left:3px solid var(--accent);background:var(--bg-raise);border-radius:0 var(--radius-sm) var(--radius-sm) 0}.proj-layout{display:grid;grid-template-columns:230px 1fr;gap:32px;align-items:start}.proj-layout>*{min-width:0}.proj-steps{position:sticky;top:80px;display:flex;flex-direction:column;gap:2px}.proj-steps button{text-align:left;padding:9px 12px;border-radius:8px;font-size:13.5px;color:var(--muted);display:flex;gap:10px;align-items:center}.proj-steps button:hover{background:var(--panel);color:var(--text)}.proj-steps button.cur{background:var(--panel-2);color:var(--text);font-weight:600}.proj-steps .snum{width:20px;height:20px;border-radius:50%;border:1.5px solid var(--line);font-size:11px;display:grid;place-items:center;flex-shrink:0;font-variant-numeric:tabular-nums}.proj-steps button.done .snum{border-color:var(--accent);color:var(--accent);background:var(--accent-soft)}@media(max-width:860px){.proj-layout{grid-template-columns:1fr;gap:16px}.proj-steps{position:static;flex-direction:row;overflow-x:auto;gap:2px 6px;padding-bottom:4px;min-width:0;max-width:100%}.proj-steps button{flex-shrink:0;white-space:nowrap}}.step-md{font-size:15px;color:#c9d3e3}.step-md p{margin:12px 0}.step-md ol,.step-md ul{padding-left:22px}.step-md li{margin:6px 0}.lesson-nav{display:flex;justify-content:space-between;gap:14px;margin-top:60px;padding-top:24px;border-top:1px solid var(--line-soft)}.lesson-nav a{text-decoration:none;padding:14px 18px;border:1px solid var(--line);border-radius:var(--radius);max-width:46%;transition:border-color .15s}.lesson-nav a:hover{border-color:var(--accent-line)}.lesson-nav .dir{font-size:12px;color:var(--faint);display:block}.lesson-nav .to{font-size:14.5px;font-weight:600}.lesson-nav .next{margin-left:auto;text-align:right}.complete-cta{margin-top:40px;display:flex;align-items:center;gap:14px;font-size:14.5px;color:var(--muted)}.complete-cta.all-done{color:#9bc9b1}@media(max-width:900px){.topbar{gap:12px}.topbar .desktop-nav,.topbar .desktop-settings{display:none}.mobile-menu-button{display:inline-flex}.topbar .spacer{min-width:0}}@media(max-width:640px){.topbar{padding:0 16px;gap:10px}.topbar .xp .xp-label{display:none}.topbar .xp b:after{content:" ✓";color:var(--ok)}.topbar-search{padding:0}.topbar-search .search-label{display:none}.page{padding:24px 16px 90px}.lesson-row .meta .pill.mins{display:none}}@media(max-width:520px){.topbar .brand span{font-size:14px}.topbar .xp{display:none}}@media(max-width:380px){.topbar .brand span{display:none}}.evidence-panel{padding:4px 18px 8px}.evidence-note{font-size:13px;color:var(--muted);border:1px dashed var(--line);border-radius:var(--radius-sm);padding:10px 14px;margin-bottom:14px}.evidence-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(260px,1fr));gap:14px}.evidence-field{display:flex;flex-direction:column;gap:6px}.evidence-field>span{font-size:13px;font-weight:600;color:#c9d3e3}.evidence-field small{font-size:12px;color:var(--faint)}.evidence-field input,.evidence-field textarea{font-family:var(--mono);font-size:12.5px;line-height:1.5;color:#dde5f1;background:var(--bg-raise);border:1px solid var(--line);border-radius:var(--radius-sm);padding:8px 10px;resize:vertical}.evidence-field input:focus,.evidence-field textarea:focus{outline:none;border-color:var(--accent-line)}.evidence-field ::placeholder{color:var(--faint);opacity:.8}@media(prefers-reduced-motion:reduce){*,*:before,*:after{transition-duration:.01ms!important;animation-duration:.01ms!important;animation-iteration-count:1!important;scroll-behavior:auto!important}.track-card:hover,.btn:active{transform:none}}.start-here{display:inline-block;margin-top:20px;padding:10px 16px;border-radius:999px;background:var(--accent-soft);border:1px solid var(--accent-line);color:var(--text);font-size:14px;text-decoration:none}.start-here b{color:var(--accent)}.start-here:hover{background:color-mix(in srgb,var(--accent) 20%,transparent)}.nav-badge{display:inline-block;margin-left:6px;min-width:16px;padding:0 5px;border-radius:999px;background:var(--accent);color:#0a0e16;font-size:11px;font-weight:700;line-height:16px;text-align:center;vertical-align:middle}.lesson-intro{margin:0 0 30px;padding:0 0 26px;border-bottom:1px solid var(--line-soft)}.lesson-intro .li-summary{margin:0 0 14px;font-size:16.5px;line-height:1.65;color:var(--text);max-width:68ch}.lesson-intro .li-cols{display:flex;gap:28px;flex-wrap:wrap}.lesson-intro .li-col{flex:1 1 240px;min-width:220px}.lesson-intro h4{margin:0 0 7px;font-size:13px;letter-spacing:.01em;color:var(--faint);font-weight:650}.lesson-intro ul{margin:0;padding-left:18px}.lesson-intro li{font-size:13.5px;color:#c9d3e3;margin:4px 0;line-height:1.45}.lesson-intro code{font-family:var(--mono);font-size:.9em;color:var(--text);background:var(--code-bg);padding:1px 5px;border-radius:5px}.lesson-wrapup{margin:26px 0 8px;display:flex;flex-direction:column;gap:18px}.lesson-wrapup h3{margin:0 0 10px;font-size:17px;letter-spacing:-.01em}.lesson-wrapup code{font-family:var(--mono);font-size:.9em;color:var(--text);background:var(--code-bg);padding:1px 5px;border-radius:5px}.lw-mistakes .mistake{padding:12px 15px;margin-bottom:10px;border-radius:var(--radius-sm);border:1px solid var(--line);background:var(--bg-raise)}.lw-mistakes .m-bad{font-size:14px;font-weight:600;color:#cf99a3}.lw-mistakes .m-why{font-size:13.5px;color:var(--muted);margin:5px 0;line-height:1.5}.lw-mistakes .m-fix{font-size:13.5px;color:#9bc9b1;font-weight:550}.lw-amrex{padding:14px 16px;border-radius:var(--radius-sm);border:1px solid var(--line);background:var(--bg-raise)}.lw-amrex p{margin:0;font-size:14px;line-height:1.55;color:#d4ddec}.lw-checklist ul{margin:0;padding-left:20px}.lw-checklist li{font-size:14px;color:#c9d3e3;margin:6px 0;line-height:1.45}.review-empty{margin:24px 0;padding:26px;text-align:center;border-radius:var(--radius);border:1px dashed var(--line);background:var(--bg-raise)}.review-empty p{margin:6px 0;font-size:16px}.review-empty .muted{color:var(--muted);font-size:13.5px;max-width:520px;margin:8px auto 0;line-height:1.5}.concept-chips{display:flex;flex-wrap:wrap;gap:8px}.concept-chip{display:inline-flex;align-items:center;gap:7px;padding:6px 10px 6px 12px;border-radius:999px;background:var(--bg-raise);border:1px solid var(--line);font-size:13px;color:#d4ddec}.concept-chip b{min-width:18px;padding:0 5px;border-radius:999px;background:color-mix(in srgb,var(--warn) 22%,transparent);color:var(--warn);font-size:11.5px;text-align:center}.lesson-row .status.review{background:color-mix(in srgb,var(--warn) 18%,transparent);color:var(--warn)}.review-row:hover{border-color:color-mix(in srgb,var(--warn) 40%,transparent)}.mode-toggle{display:flex;align-items:center;flex-wrap:wrap;gap:8px 14px;margin:0 0 26px;padding:0}.mt-label{font-size:12.5px;letter-spacing:.02em;color:var(--faint);font-weight:600}.mt-seg{display:inline-flex;border:1px solid var(--line);border-radius:999px;overflow:hidden}.mt-seg.full{display:flex;width:100%;border-radius:10px}.mt-seg button{padding:5px 14px;font-size:13px;font-weight:600;color:var(--muted);background:transparent;border-right:1px solid var(--line)}.mt-seg.full button{flex:1}.mt-seg button:last-child{border-right:none}.mt-seg button.on{background:var(--panel-2);color:var(--text);box-shadow:inset 0 -2px 0 0 var(--accent)}.mt-seg button:not(.on):hover{color:var(--text);background:var(--panel)}.mt-blurb{flex:1 1 260px;min-width:220px;font-size:12.5px;color:var(--faint);line-height:1.45}.settings-wrap{position:relative}.settings-gear{width:34px;height:34px;border-radius:9px;font-size:17px;color:var(--muted);border:1px solid var(--line);background:var(--panel)}.settings-gear.labelled{width:100%;height:auto;justify-content:flex-start;display:flex;align-items:center;gap:10px;padding:10px 12px;font-size:14px}.settings-gear:hover{color:var(--text);border-color:var(--accent-line)}.settings-scrim{position:fixed;top:0;right:0;bottom:0;left:0;z-index:60}.settings-panel{position:absolute;right:0;top:42px;z-index:61;width:320px;max-width:88vw;padding:16px;border-radius:var(--radius);border:1px solid var(--line);background:var(--panel);box-shadow:0 20px 60px -20px #000000b3}.sp-title-row{display:flex;align-items:center;gap:12px;margin-bottom:12px}.sp-title{font-weight:700;font-size:15px}.sp-close{margin-left:auto;width:30px;height:30px;display:grid;place-items:center;border:1px solid var(--line);border-radius:8px;color:var(--muted);font-size:21px;line-height:1}.sp-close:hover{color:var(--text);border-color:var(--accent-line)}.sp-section{margin-bottom:16px}.sp-h{font-size:12.5px;letter-spacing:.02em;color:var(--faint);font-weight:650;margin-bottom:8px}.sp-blurb{margin:8px 0 0;font-size:12.5px;color:var(--muted);line-height:1.5}.sp-toggle{display:flex;align-items:flex-start;gap:9px;padding:6px 0;font-size:13.5px;color:#c9d3e3;cursor:pointer}.sp-toggle input{margin-top:2px;accent-color:var(--accent);width:15px;height:15px}.sp-custom{color:var(--accent);font-style:normal;font-size:11px}.sp-foot{margin:4px 0 0;font-size:11.5px;color:var(--faint);line-height:1.45}.plain-card{margin:22px 0;padding:4px 18px 14px;border-radius:var(--radius);border:1px solid var(--line);background:var(--bg-raise)}.pc-tag{display:inline-block;margin:12px 0 6px;padding:3px 11px;border-radius:999px;font-size:12px;font-weight:600;letter-spacing:.02em;color:var(--muted);background:var(--panel-2)}.pc-row{display:flex;gap:13px;padding:8px 0}.pc-ico{font-size:18px;line-height:1.5;flex-shrink:0}.pc-label{font-size:12px;letter-spacing:.02em;color:var(--faint);font-weight:650;margin-bottom:3px}.pc-text{font-size:15.5px;line-height:1.6;color:var(--text)}.pc-row:last-child .pc-text{font-style:italic;color:#cdd8ea}.takeaway{display:flex;gap:12px;align-items:baseline;margin:20px 0;padding:13px 16px;border-radius:var(--radius-sm);border-left:3px solid var(--ok);background:color-mix(in srgb,var(--ok) 7%,var(--bg-raise))}.tk-label{font-size:12px;letter-spacing:.02em;font-weight:650;color:var(--ok);flex-shrink:0}.takeaway>div{font-size:15.5px;color:var(--text);line-height:1.55}.recall{margin:20px 0;padding:14px 16px;border-radius:var(--radius);border:1px dashed var(--line);background:var(--bg-raise)}.rc-head{font-weight:650;font-size:13px;color:var(--muted);margin-bottom:7px}.rc-prompt{font-size:15.5px;color:var(--text);line-height:1.55}.rc-btn{margin-top:10px}.rc-answer{margin-top:10px;padding:10px 13px;border-radius:8px;background:var(--panel);font-size:14.5px;color:#cdd8ea;line-height:1.55}.breakdown{margin:16px 0;padding:12px 15px;border-radius:var(--radius-sm);border:1px solid var(--line);background:var(--bg-raise)}.bd-sentence{font-size:15px;font-style:italic;color:#cdd8ea;line-height:1.55}.bd-body{margin-top:10px}.bd-row{display:flex;gap:12px;padding:5px 0;font-size:14.5px}.bd-row b{flex:0 0 92px;color:var(--faint);font-weight:600}.bd-row span{color:var(--text)}.bd-remember{margin:8px 0;padding:9px 12px;border-radius:8px;background:color-mix(in srgb,var(--ok) 8%,transparent);color:#9bc9b1;font-size:14.5px}.bd-btn{margin-top:6px}.speak{margin:20px 0;padding:14px 16px;border-radius:var(--radius);border:1px solid var(--line);background:var(--bg-raise)}.sp-head{font-weight:650;font-size:13.5px;color:var(--muted);margin-bottom:8px}.speak ul{margin:0;padding-left:20px}.speak li{font-size:15px;color:var(--text);margin:6px 0;line-height:1.5}.sp-recover{margin-top:10px;font-size:13px;color:var(--muted);font-style:italic}.gloss-inline{display:flex;flex-direction:column;gap:12px;margin:20px 0}.gloss-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(320px,1fr));gap:14px;margin-top:18px}.gloss-card{padding:15px 16px;border-radius:var(--radius);border:1px solid var(--line);background:var(--bg-raise)}.gc-term{font-size:17px;font-weight:700;color:var(--text);margin-bottom:9px;letter-spacing:-.01em}.gc-row{display:flex;gap:10px;padding:5px 0;font-size:14px;line-height:1.55}.gc-k{flex:0 0 96px;font-size:12px;letter-spacing:.01em;color:var(--faint);font-weight:650;padding-top:2px}.gc-row span:last-child{color:#cdd8ea}.gc-code{margin:10px 0 0;padding:9px 12px;border-radius:8px;background:var(--code-bg);border:1px solid var(--line);font-family:var(--mono);font-size:12.5px;white-space:pre-wrap;color:#bfcde2;overflow-x:auto}.gloss-search{width:100%;box-sizing:border-box;margin-top:6px;padding:11px 15px;border-radius:10px;border:1px solid var(--line);background:var(--panel);color:var(--text);font-family:var(--sans);font-size:15px}.gloss-search::placeholder{color:var(--faint)}.one-concept{border:1px solid var(--line);border-radius:var(--radius);padding:4px 22px 18px;background:var(--bg-raise)}.oc-bar{display:flex;align-items:baseline;gap:12px;padding:14px 0 4px;flex-wrap:wrap}.oc-count{font-size:12.5px;letter-spacing:.02em;color:var(--faint);font-weight:650}.oc-title{font-size:15px;color:var(--muted)}.oc-track{display:flex;gap:5px;margin:8px 0 4px}.oc-track i{flex:1;height:4px;border-radius:999px;background:var(--line)}.oc-track i.on{background:var(--accent)}.oc-nav{display:flex;align-items:center;gap:14px;margin-top:18px;padding-top:14px;border-top:1px solid var(--line-soft);flex-wrap:wrap}.oc-mid{flex:1 1 200px;font-size:12.5px;color:var(--faint);text-align:center}.oc-done{font-size:13.5px;color:var(--ok);font-weight:600}.ml-details>summary,.lesson-wrapup.collapsed>summary{cursor:pointer;list-style:none;font-weight:600;font-size:14px;color:var(--text);padding:4px 0}.ml-details>summary::-webkit-details-marker,.lesson-wrapup.collapsed>summary::-webkit-details-marker{display:none}.ml-details[open]>summary,.lesson-wrapup.collapsed[open]>summary{margin-bottom:8px;color:var(--muted)}.lesson-wrapup.collapsed{display:block;margin:26px 0 8px;padding:12px 15px;border:1px solid var(--line);border-radius:var(--radius);background:var(--bg-raise)}.lesson-wrapup.collapsed>:not(summary){margin-top:18px}.check-more{margin:2px 18px 6px;font-size:12.5px}.status-meter{height:8px;border-radius:999px;background:var(--line);overflow:hidden;max-width:460px;margin:6px 0}.status-meter i{display:block;height:100%;background:var(--ok)}.status-num{font-size:14px;color:var(--muted)}.status-num b{color:var(--text)}.status-unit{margin:6px 0 16px}.status-unit-title{font-size:13px;color:var(--faint);letter-spacing:.02em;font-weight:650;margin:10px 0 8px}.status-rows{display:flex;flex-direction:column;gap:5px}.status-row{display:flex;align-items:center;gap:12px;padding:9px 13px;border-radius:var(--radius-sm);border:1px solid var(--line);background:var(--bg-raise);text-decoration:none}.status-row:hover{border-color:var(--accent-line)}.status-tier{flex:0 0 auto;font-size:11.5px;font-weight:700;padding:3px 9px;border-radius:999px}.status-tier.accessible{color:#9bc9b1;background:color-mix(in srgb,var(--ok) 14%,transparent)}.status-tier.legacy{color:var(--faint);background:var(--panel)}.status-lname{flex:1;font-size:14.5px;color:var(--text)}.status-flag{font-size:11px;color:var(--amrex);background:color-mix(in srgb,var(--amrex) 12%,transparent);padding:2px 8px;border-radius:999px}:root[data-large-text=true] .lesson-body{max-width:66ch}:root[data-large-text=true] .lesson-body p,:root[data-large-text=true] .lesson-body li{font-size:17.5px;line-height:1.72}:root[data-large-text=true] .lesson-body p{margin:18px 0}:root[data-large-text=true] .lesson-body h2{margin-top:40px}:root[data-large-text=true] .ex-instructions{font-size:16px;line-height:1.6}:root[data-large-text=true] .pc-text,:root[data-large-text=true] .rc-prompt,:root[data-large-text=true] .takeaway>div{font-size:17px}:root[data-calm=true] .hero .mesh{display:none}:root[data-calm=true] .continue-strip,:root[data-calm=true] .start-here{border-color:var(--line)}:root[data-calm=true] .lesson-body h2:before{opacity:.5}:root[data-calm=true] .codeblock{box-shadow:none}@media(max-width:640px){.settings-panel{position:fixed;right:8px;left:8px;width:auto;top:60px}.mode-toggle{gap:8px 10px}}:root[data-theme=light]{--bg: #f6f7f9;--bg-raise: #ffffff;--panel: #ffffff;--panel-2: #eef1f5;--line: #d7dce4;--line-soft: #e6e9ef;--text: #18202c;--muted: #566072;--faint: #808a99;--code-bg: #0c1119;--term-bg: #070a10;color-scheme:light}:root[data-theme=light] body{background:var(--bg);color:var(--text)}:root[data-theme=light] .lesson-body p,:root[data-theme=light] .lesson-body ul,:root[data-theme=light] .lesson-body li,:root[data-theme=light] table.tbl td,:root[data-theme=light] .pc-text,:root[data-theme=light] .rc-prompt,:root[data-theme=light] .rc-answer,:root[data-theme=light] .bd-sentence,:root[data-theme=light] .bd-row span,:root[data-theme=light] .gc-row span:last-child,:root[data-theme=light] .takeaway>div,:root[data-theme=light] .speak li,:root[data-theme=light] .lesson-intro li,:root[data-theme=light] .lesson-intro .li-summary,:root[data-theme=light] .lw-checklist li,:root[data-theme=light] .lw-amrex p,:root[data-theme=light] .lw-mistakes .m-why,:root[data-theme=light] .ex-instructions,:root[data-theme=light] .status-lname,:root[data-theme=light] .check-list li{color:#232c3a}:root[data-theme=light] .lw-mistakes .m-bad{color:#b0344a}:root[data-theme=light] .lw-mistakes .m-fix,:root[data-theme=light] .pass-banner{color:#157347}:root[data-theme=light] .pass-banner{background:color-mix(in srgb,var(--ok) 14%,white);border-color:color-mix(in srgb,var(--ok) 45%,white)}:root[data-theme=light] .lesson-body p code,:root[data-theme=light] .lesson-body li code,:root[data-theme=light] .note code,:root[data-theme=light] .ex-instructions code,:root[data-theme=light] .quiz-q code,:root[data-theme=light] td code,:root[data-theme=light] th code,:root[data-theme=light] .step-md code,:root[data-theme=light] .pc-text code,:root[data-theme=light] .ml-lead code,:root[data-theme=light] .ml-steps code,:root[data-theme=light] .lesson-intro code,:root[data-theme=light] .lesson-wrapup code{background:#eef1f6;color:#1c3d5a;border:1px solid #dfe4ec}:root[data-theme=light] .t-shell .lesson-body code,:root[data-theme=light] .t-cpp .lesson-body code,:root[data-theme=light] .t-amrex .lesson-body code{color:#1c3d5a}:root[data-theme=light] .plain-card{background:#fff}:root[data-theme=light] .recall{background:#fff}:root[data-theme=light] .speak{background:#fff}:root[data-theme=light] .machine-loop{background:#fff}:root[data-theme=light] .lw-amrex{background:#fff}:root[data-theme=light] .takeaway{background:#eefaf2}:root[data-theme=light] .breakdown,:root[data-theme=light] .gloss-card,:root[data-theme=light] .status-row{background:#fff}:root[data-theme=light] .note.tip{background:#eefaf2}:root[data-theme=light] .note.warn{background:#fdf6e3}:root[data-theme=light] .note.info{background:#eef4ff}:root[data-theme=light] .compiler-lab{background:#fdeef0}:root[data-theme=light] .settings-panel{box-shadow:0 18px 50px -20px #1e283c59}:root[data-theme=light] .topbar{border-bottom-color:var(--line)}:root[data-theme=light] .nav-badge{color:#fff}:root[data-theme=light] .mt-seg button.on{background:var(--panel-2);color:var(--text)}.ex-card.folded{background:var(--bg-raise)}.ex-card.folded .ex-head{margin:0;padding:13px 18px}.ex-start{margin-left:auto;font-size:13px;padding:6px 14px;white-space:nowrap}.ossu-group{margin-top:34px}.ossu-group .unit-head h2{font-size:15px;color:var(--muted);font-weight:500}.ossu-section .path-phase-num{min-width:44px}.ossu-course{align-items:start}.ossu-course .path-item-copy b a{color:var(--text);text-decoration:none}.ossu-course .path-item-copy b a:hover{color:var(--accent);text-decoration:underline}.ossu-course.done .path-item-copy b a{color:var(--muted)}.ossu-check{width:28px;height:28px;display:grid;place-items:center;border:1px solid var(--line);border-radius:50%;color:var(--accent);font-size:13px;background:transparent;cursor:pointer}.ossu-check:hover{border-color:var(--accent-line);background:var(--accent-soft)}.ossu-course.done .ossu-check{border-color:var(--accent);background:var(--accent-soft)}.ossu-hpc{margin-left:8px;padding:1.5px 7px;border-radius:99px;border:1px solid color-mix(in srgb,var(--ok) 45%,transparent);color:var(--ok);font-size:10px;font-weight:700;text-transform:uppercase;letter-spacing:.06em;white-space:nowrap;vertical-align:2px}.ossu-note-pill{margin-left:8px;padding:1.5px 7px;border-radius:99px;border:1px solid var(--line);color:var(--muted);font-size:10.5px;white-space:nowrap;vertical-align:2px}.ossu-academy-note{margin-top:5px;color:var(--accent);font-size:11.5px;font-style:normal}.ossu-rule{margin-top:7px!important;color:var(--warn)!important;font-size:12.5px!important}.ossu-topics{display:flex;flex-wrap:wrap;gap:5px;margin:9px 0 0!important}.ossu-topics span{padding:2px 8px;border:1px solid var(--line-soft);border-radius:99px;color:var(--faint);font-size:10.5px}.ossu-fit{margin-top:26px}.ossu-attribution{margin:30px 0 8px;color:var(--faint);font-size:12px;max-width:640px}.ossu-teaser{margin-top:30px}.ossu-teaser .today-actions{margin-top:12px;display:flex;align-items:center;gap:14px;flex-wrap:wrap}.ossu-teaser-count{color:var(--muted);font-size:12.5px}@media(max-width:640px){.ossu-course{grid-template-columns:30px minmax(0,1fr)}.ossu-course .path-item-meta{grid-column:2;justify-content:flex-start}}.shell-pane{margin:12px 0 4px}.wasm-runner .shell-pane{margin:12px 0 8px}.shell-scroll{height:auto;min-height:90px;max-height:380px;white-space:pre-wrap;word-break:break-word;cursor:default}.sh-status{color:var(--faint)}.sh-diag{color:#b9c2d0}.sh-stdout{color:#cfd8d3}.sh-stderr{color:#cf99a3}.playground{max-width:860px}.playground .track-hero p{max-width:68ch}.pg-editor textarea{min-height:320px}.pg-stdin{margin:12px 0 0;border:1px solid var(--line);border-radius:var(--radius-sm);background:var(--bg-raise);padding:10px 14px}.pg-stdin>summary{cursor:pointer;font-size:13.5px;font-weight:600;color:var(--muted);list-style:none}.pg-stdin>summary::-webkit-details-marker{display:none}.pg-stdin textarea{width:100%;box-sizing:border-box;margin-top:10px;min-height:70px;resize:vertical;font-family:var(--mono);font-size:12.5px;padding:8px 10px;border:1px solid var(--line);border-radius:8px;background:var(--term-bg);color:var(--text)}.pg-actions{padding:12px 0}.pg-tip{color:var(--faint);font-size:12px;margin-left:auto}.pg-credit{margin-top:22px;color:var(--faint);font-size:12.5px;max-width:68ch}.pg-credit a{color:var(--muted)}.online-runner{border-left:3px solid color-mix(in srgb,var(--ok) 55%,transparent)}.runner-output{margin-top:12px}.runner-output-label{color:var(--muted);font-size:12.5px;letter-spacing:.02em;font-weight:600;margin:10px 0 5px}.runner-output pre{margin:0;padding:11px 13px;border:1px solid var(--line);border-radius:9px;background:var(--bg);color:var(--text);font-family:var(--mono);font-size:12.5px;line-height:1.55;overflow-x:auto;white-space:pre-wrap;word-break:break-word}.runner-exit{margin:8px 0 0;color:var(--warn);font-size:12.5px}.runner-diagnostics{margin-top:12px}
