:root{--paper:#fff;--ink:#202833;--muted:#596575;--line:#dce2e8;--accent:#225a75;--soft:#f3f6f8;--code:#192734}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:2rem}body{margin:0;background:var(--paper);color:var(--ink);font:18px/1.7 'Segoe UI',system-ui,sans-serif}a{color:var(--accent);text-underline-offset:4px}button,input{font:inherit}button{cursor:pointer;border:1px solid var(--line);border-radius:5px;background:#fff;color:var(--ink);padding:.5rem .85rem}button:hover{border-color:var(--accent);background:var(--soft)}button:disabled{opacity:.5;cursor:default}:focus-visible{outline:3px solid var(--accent);outline-offset:4px}.skip{position:absolute;top:-100px;left:20px;background:#fff;padding:12px;z-index:5}.skip:focus{top:8px}header{display:flex;align-items:center;gap:2rem;border-bottom:1px solid var(--line);padding:20px 5vw}header .brand{font-size:24px;color:var(--ink);text-decoration:none;letter-spacing:-.7px}header span{color:var(--muted);font-size:15px}.print{margin-left:auto;font-size:14px}.layout{display:grid;grid-template-columns:225px minmax(0,850px);gap:clamp(35px,6vw,100px);max-width:1250px;margin:0 auto;padding:55px 35px}.sidebar{position:sticky;top:30px;align-self:start;font-size:15px}.sidebar nav{display:grid;gap:4px}.sidebar a{padding:8px 12px;color:var(--muted);text-decoration:none;border-left:3px solid transparent}.sidebar a:hover{color:var(--accent);background:var(--soft)}.sidebar a[aria-current]{color:var(--accent);border-left-color:var(--accent);background:var(--soft);font-weight:600}.home{display:block;margin-bottom:15px}.toc{margin-top:30px;padding-top:22px;border-top:1px solid var(--line)}.toc strong{padding-left:15px;margin-bottom:8px}main{min-width:0}h1{font-size:clamp(42px,5vw,64px);line-height:1.12;font-weight:650;letter-spacing:-2px;margin:10px 0 20px}h2{font-size:30px;line-height:1.25;letter-spacing:-.65px;margin:0 0 25px}h3{font-size:21px;line-height:1.4;margin:30px 0 12px}p{max-width:74ch;margin:0 0 20px}.intro-label{color:var(--muted);font-size:15px;margin:0}.lead{font-size:23px;color:var(--muted);line-height:1.5}.goal{margin-top:32px;padding-left:22px;border-left:3px solid var(--accent);font-size:17px}.lesson-intro{padding-bottom:38px}section{border-top:1px solid var(--line);padding:38px 0 22px}blockquote{margin:30px 0;padding:20px 24px;background:var(--soft);border-left:3px solid var(--accent);font-size:22px;line-height:1.5}.prompt{font-size:16px;color:var(--muted)}code,samp{font-family:Consolas,'Liberation Mono',monospace;font-size:.9em}p code,dd code,li code{background:var(--soft);padding:2px 5px;border-radius:3px}.code-head{display:flex;justify-content:space-between;align-items:center;background:var(--code);color:#ced8e1;font-size:13px;padding:10px 18px;border-radius:6px 6px 0 0;margin-top:24px}.code-head button{font-size:12px;background:transparent;color:#fff;border-color:#8193a5;padding:4px 10px}pre{margin:0 0 24px;background:var(--code);color:#f0f4f7;padding:22px;overflow:auto;line-height:1.65;border-radius:0 0 6px 6px;font-size:16px;tab-size:4}pre code{font-size:inherit}.result{font-size:16px;padding:12px 0;color:var(--muted)}dl{display:grid;grid-template-columns:110px 1fr;gap:15px 20px;margin:25px 0}dt{font-weight:650}dd{margin:0}.note{border-left:3px solid #a0aeb9;background:var(--soft);padding:20px 24px;margin:28px 0}.note p{font-size:16px;margin:8px 0 0}.exercise{margin:0 0 28px;padding-bottom:26px;border-bottom:1px solid var(--line)}.exercise h3{margin-top:0}.exercise p{margin-bottom:12px}details{margin-top:10px}summary{cursor:pointer;color:var(--accent);font-size:16px;padding:7px 0}details>div{padding:14px 18px;border-left:2px solid var(--line);margin:8px 0;font-size:16px}details pre{font-size:14px}.closing{margin-top:6px}.lesson-nav{display:flex;flex-wrap:wrap;justify-content:space-between;gap:20px;padding:30px 0;border-top:1px solid var(--line);font-size:16px}.course-list{padding:0;list-style:none;counter-reset:lesson}.course-list li{counter-increment:lesson;border-bottom:1px solid var(--line)}.course-list a{display:grid;grid-template-columns:35px 1fr auto;align-items:center;padding:22px 0;text-decoration:none;column-gap:16px}.course-list a:before{content:counter(lesson);grid-row:span 2;color:var(--muted)}.course-list h3{margin:0;color:var(--ink)}.course-list p{grid-column:2;margin:2px 0 0;color:var(--muted);font-size:16px}.course-list span{grid-column:3;grid-row:1/3;font-size:14px}.course-list a:hover h3{text-decoration:underline;text-underline-offset:5px}.table-wrap{overflow:auto}table{width:100%;border-collapse:collapse;font-size:16px;text-align:left}caption{text-align:left;color:var(--muted);font-size:14px;margin-bottom:12px}th,td{padding:13px 12px;border-bottom:1px solid var(--line)}thead{background:var(--soft)}.demo{border:1px solid var(--line);padding:25px;border-radius:6px;margin-bottom:32px}.demo h3{margin:0 0 12px}.demo p,.demo label{font-size:16px}.input-row{display:flex;gap:10px;margin:8px 0}input{min-width:0;width:100%;border:1px solid #8a99a8;border-radius:4px;padding:8px 12px;font-family:Consolas,monospace}.input-row button{white-space:nowrap;font-size:14px}.array{display:flex;flex-wrap:wrap;gap:10px;padding:0;list-style:none;margin:25px 0}.array li{background:var(--soft);border-bottom:4px solid transparent;min-width:55px;text-align:center;padding:12px;font:24px Consolas,monospace}.array li.active{border-color:var(--accent);font-weight:bold}.step{min-height:65px}.controls{display:flex;flex-wrap:wrap;gap:10px}.controls button{font-size:15px}.demo-caption{color:var(--muted);margin:18px 0 0}.error{color:#9b2525;margin:8px 0}.error:empty{display:none}footer{max-width:1250px;padding:25px 35px;margin:auto;border-top:1px solid var(--line);color:var(--muted);font-size:14px}.status{position:fixed;bottom:20px;right:20px;background:var(--code);color:#fff;padding:10px 20px;border-radius:5px;font-size:14px}.status:empty{display:none}@media(max-width:850px){.layout{grid-template-columns:1fr;padding:25px 22px;gap:25px}.sidebar{position:static}.sidebar nav:not(.toc){display:flex;overflow:auto;gap:6px;padding-bottom:8px}.sidebar nav:not(.toc) a{white-space:nowrap;border-left:0;border-bottom:3px solid transparent}.sidebar nav:not(.toc) a[aria-current]{border-bottom-color:var(--accent)}.sidebar .toc{display:flex;flex-wrap:wrap;gap:4px;margin-top:15px;padding-top:15px}.toc strong{width:100%}.home{margin:0}.sidebar a{padding:6px 9px}.lesson-intro{padding-bottom:20px}header{padding:18px 22px;gap:15px}header span{display:none}body{font-size:17px}.course-list span{display:none}.course-list a{grid-template-columns:28px 1fr}.input-row{flex-wrap:wrap}.input-row button{width:100%}dl{grid-template-columns:90px 1fr}pre{font-size:14px}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}@media print{header,.sidebar,footer,.status,.copy,.lesson-nav,.controls,.input-row{display:none!important}.layout{display:block;padding:0;max-width:none}body{font-size:11pt;color:#000}h1{font-size:28pt}h2{font-size:19pt}section{padding:20px 0}pre,.code-head{background:#f2f2f2;color:#000;white-space:pre-wrap;font-size:10pt}.exercise{break-inside:avoid}details:not([open])>div{display:none}.demo{break-inside:avoid}}

.sidebar{min-width:0}

/* ===== Destaques de conteúdo ===== */
:root{--accent-soft:#e9f2f6;--warn:#9a5a00;--warn-soft:#fdf5e8;--ok:#2d7550;--ok-soft:#ebf5ef;--hack-bg:#0e1620;--hack-panel:#152230;--hack-ink:#d6e2ea;--hack-muted:#8fa3b3;--hack-accent:#5fd3a5}
.key{background:var(--accent-soft);border-left:4px solid var(--accent);padding:18px 24px;margin:28px 0;border-radius:0 6px 6px 0}
.key>strong:first-child,.pitfall>strong:first-child,.tip>strong:first-child{display:block;font-size:13px;letter-spacing:.08em;text-transform:uppercase;margin-bottom:6px}
.key>strong:first-child{color:var(--accent)}
.key p,.pitfall p,.tip p{font-size:16px;margin:6px 0 0}
.key ul,.pitfall ul,.tip ul,.key ol,.pitfall ol,.tip ol{font-size:16px;margin:8px 0 0;padding-left:22px}
.pitfall{background:var(--warn-soft);border-left:4px solid var(--warn);padding:18px 24px;margin:28px 0;border-radius:0 6px 6px 0}
.pitfall>strong:first-child{color:var(--warn)}
.tip{background:var(--ok-soft);border-left:4px solid var(--ok);padding:18px 24px;margin:28px 0;border-radius:0 6px 6px 0}
.tip>strong:first-child{color:var(--ok)}
.key pre,.pitfall pre,.tip pre{font-size:14px}
mark{background:#fff1b8;color:inherit;padding:0 3px;border-radius:2px}
.formula{font:17px Consolas,'Liberation Mono',monospace;background:var(--soft);padding:12px 18px;border-radius:5px;display:inline-block;margin:4px 0 20px}
.level{display:inline-block;vertical-align:middle;font-size:12px;font-weight:600;letter-spacing:.04em;text-transform:uppercase;padding:2px 9px;border-radius:20px;margin-left:10px;border:1px solid currentColor}
.level.basico{color:var(--ok)}
.level.medio{color:var(--accent)}
.level.avancado{color:var(--warn)}
.checklist{list-style:none;padding:0;margin:20px 0}
.checklist li{position:relative;padding:6px 0 6px 32px;font-size:17px}
.checklist li:before{content:"✓";position:absolute;left:4px;top:6px;color:var(--ok);font-weight:700}
.steps{counter-reset:passo;list-style:none;padding:0;margin:24px 0}
.steps li{counter-increment:passo;position:relative;padding:4px 0 16px 52px}
.steps li:before{content:counter(passo);position:absolute;left:0;top:2px;width:34px;height:34px;border-radius:50%;background:var(--accent);color:#fff;font-weight:700;display:grid;place-items:center;font-size:16px}
.steps strong{display:block}
.grid-2{display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:18px;margin:24px 0}
.grid-4{grid-template-columns:repeat(4,1fr)}
@media(max-width:1100px){.grid-4{grid-template-columns:repeat(2,1fr)}}
@media(max-width:520px){.grid-4{grid-template-columns:1fr}}
.card{border:1px solid var(--line);border-radius:6px;padding:18px 20px}
.card h3{margin:0 0 8px;font-size:18px}
.card p{font-size:16px;margin:0}
.badge-hack{display:inline-block;font:600 12px Consolas,monospace;letter-spacing:.06em;color:var(--hack-accent);background:var(--hack-bg);padding:3px 10px;border-radius:4px}
.course-list .badge-hack{margin-left:8px;font-size:11px;vertical-align:middle}

.io-plain{background:var(--soft);border-left:3px solid #a0aeb9;padding:12px 18px;border-radius:0 5px 5px 0;margin:0 0 16px;overflow-x:auto}
.io-plain samp{white-space:pre;font-size:15px}
.exercise ol{font-size:17px;margin:0 0 12px}
.exercise details>div p{margin:10px 0 0}

/* ===== Aprofundamento, glossário e rótulos ===== */
.tag-opcional{display:inline-block;vertical-align:middle;font-size:12px;font-weight:600;letter-spacing:.04em;text-transform:uppercase;color:var(--muted);border:1px dashed var(--muted);border-radius:20px;padding:1px 10px;margin-left:10px}
h2 .tag-opcional{font-size:13px}
.palavras{font-size:15px;color:var(--muted);margin:18px 0 0;padding:12px 16px;background:var(--soft);border-radius:6px}
.palavras a{white-space:nowrap}
.glossario{display:block;margin:0}
.glossario dt{font-size:19px;font-weight:700;margin:26px 0 6px;scroll-margin-top:20px}
.glossario dt:target{color:var(--accent)}
.glossario dt:target+dd{background:var(--accent-soft);border-radius:6px}
.glossario dd{margin:0;padding:6px 10px 10px 0;border-bottom:1px solid var(--line)}
.glos-aula{display:inline-block;font-size:14px;margin-left:6px}
.code-head span code{background:transparent;color:#fff;padding:0}

/* ===== Figuras ===== */
.reveal{margin:4px 0 0}
.reveal>summary{font-weight:600}
.reveal>div{border-left:0;padding:6px 0 0;margin:0}
.figure{margin:12px 0 28px}
.table-wrap{margin-bottom:20px}
.figure-scroll{overflow-x:auto}
.figure svg{display:block;width:100%;min-width:620px;height:auto;font:14px 'Segoe UI',system-ui,sans-serif}
.figure figcaption{font-size:15px;color:var(--muted);margin-top:12px;max-width:74ch}
.fig-panel{fill:var(--soft)}
.fig-title{font-size:16px;font-weight:700;fill:var(--ink)}
.fig-label{font-size:13px;fill:var(--muted);letter-spacing:.03em}
.fig-mono,.fig-code{font-family:Consolas,'Liberation Mono',monospace;fill:var(--muted)}
.fig-mono{font-size:13px}
.fig-code{font-size:12px}
.fig-idx{font:13px Consolas,'Liberation Mono',monospace;fill:var(--muted)}
.fig-row text{fill:var(--ink)}
.fig-row .fig-idx{fill:var(--muted)}
.fig-box{fill:#fff;stroke:#b8c4cf}
.fig-box-bad{fill:#fdecea;stroke:#b3261e}
.fig-link{stroke:#8a99a8;stroke-width:1.5;stroke-dasharray:4 4}
.fig-bad{stroke:#b3261e;stroke-width:2}
.fig-bad-dot{fill:#fff;stroke:#b3261e;stroke-width:1.5}
.fig-row .fig-mark{fill:#b3261e;font-weight:700;text-anchor:middle}
.fig-bad-text{fill:#b3261e;font-weight:600}
.fig-card{fill:#fff;stroke:var(--accent);stroke-width:1.5}
.fig-card-ok{stroke:var(--ok);fill:var(--ok-soft)}
.fig-split{stroke:#c9d3dc}
.fig-row .fig-strong{font-weight:700}
.fig-row .fig-field{fill:var(--muted);font-family:Consolas,'Liberation Mono',monospace;font-size:13px}
.fig-move{stroke:var(--ok);stroke-width:2}
.fig-ok-fill{fill:var(--ok)}
.fig-ok-text{fill:var(--ok);font-weight:600}
.fig-cell{fill:#fff;stroke:#8a99a8;stroke-width:1.5}
.fig-cell-hl{fill:#fff8d6;stroke:var(--accent);stroke-width:2.5}
.fig-cell-end{fill:none;stroke:var(--warn);stroke-width:1.5;stroke-dasharray:6 5}
.fig-val{font:600 24px Consolas,'Liberation Mono',monospace;fill:var(--ink);text-anchor:middle}
.fig-idx2{font:15px Consolas,'Liberation Mono',monospace;fill:var(--ink);text-anchor:middle}
.fig-addr{font:13px Consolas,'Liberation Mono',monospace;fill:var(--muted);text-anchor:middle}
.fig-ptr{font:600 16px Consolas,'Liberation Mono',monospace;fill:var(--accent)}
.fig-ptr-line{stroke:var(--accent);stroke-width:2}
.fig-ptr-fill{fill:var(--accent)}
.fig-note{font-size:14px;fill:var(--ink)}
.fig-warn{font:600 16px Consolas,'Liberation Mono',monospace;fill:var(--warn)}
.fig-warn-small{font-size:13px;fill:var(--warn);text-anchor:middle}
.fig-warn-line{stroke:var(--warn);stroke-width:2;stroke-dasharray:5 4}
.fig-warn-fill{fill:var(--warn)}
.fig-brace{stroke:var(--muted);stroke-width:1.5}
.fig-c{text-anchor:middle}
.fig-bold{font-size:15px;font-weight:700;fill:var(--ink)}
.fig-small{font-size:13px;fill:var(--muted)}
.fig-text{font-size:14px;fill:var(--ink)}
.fig-code-t{font:14px Consolas,'Liberation Mono',monospace;fill:var(--ink)}
.fig-ret{font-size:15px;font-weight:700;fill:var(--ok)}
.fig-ret-small{font-size:13px;fill:var(--ok)}
.fig-ret-line{stroke:var(--ok);stroke-width:2}
.fig-folder{fill:#fff;stroke:var(--accent);stroke-width:1.5}
.fig-folder-tab{fill:var(--accent-soft);stroke:var(--accent);stroke-width:1.5}
.fig-frame{fill:#fff;stroke:var(--accent);stroke-width:1.5}
.fig-frame-base{fill:var(--ok-soft);stroke:var(--ok);stroke-width:1.5}
.fig-cell-off{fill:#eef1f4;stroke:#d5dce3}
.fig-val-s{font:600 16px Consolas,'Liberation Mono',monospace;fill:var(--ink);text-anchor:middle}
.fig-val-s.fig-cell-off-t{fill:#a9b4bf;font-weight:400}
.fig-cell-found{fill:var(--ok-soft);stroke:var(--ok);stroke-width:2.5}
.fig-node{fill:#fff;stroke:#8a99a8;stroke-width:1.5}
.fig-node-rep3{fill:var(--warn-soft);stroke:var(--warn);stroke-width:2}
.fig-node-rep2{fill:var(--accent-soft);stroke:var(--accent);stroke-width:2}
.fig-node-base{fill:#eef1f4;stroke:#c3ccd5}
.fig-edge{stroke:#a6b2be;stroke-width:1.5}
.fig-path{stroke:var(--accent);stroke-width:3.5}
.fig-dot{fill:var(--accent)}
.fig-leaf{fill:#fff;stroke:#8a99a8}
.fig-leaf-hl{fill:#fff8d6;stroke:var(--accent);stroke-width:2.5}
.fig-edge-label{font-size:12px;fill:var(--muted)}
.fig-cell-done{fill:var(--ok-soft);stroke:var(--ok);stroke-width:1.5}
.fig-lbl-troca{font-size:14px;font-weight:600;fill:var(--warn)}
.fig-lbl-ok{font-size:14px;fill:var(--muted)}
.fig-lbl-done{font-size:14px;font-weight:600;fill:var(--ok)}
.fig-arc{stroke:var(--warn);stroke-width:2}
.fig-arc-tag{fill:#fff;stroke:var(--warn);stroke-width:1}
.fig-arc-lbl{font:600 12px Consolas,'Liberation Mono',monospace;fill:var(--warn);text-anchor:middle}
.fig-big{font-size:26px;font-weight:700;fill:var(--warn)}
.fig-chip{fill:#fff;stroke:#b8c4cf}
.fig-chip-a{fill:var(--accent-soft);stroke:var(--accent);stroke-width:2}
.fig-chip-c{fill:var(--warn-soft);stroke:var(--warn);stroke-width:2}
.fig-chip-pos{font-weight:700;fill:var(--muted)}
.fig-arrow{stroke:var(--muted);stroke-width:2}
.fig-arrow-fill{fill:var(--muted)}
.fig-warn-small2{font-size:13px;fill:var(--warn)}
.fig-cell-r{fill:var(--warn-soft);stroke:var(--warn);stroke-width:1.5}
.fig-merge-r{stroke:var(--warn);stroke-width:1.8}
.fig-merge-l{stroke:var(--muted);stroke-width:1.5;stroke-dasharray:4 4}
.fig-cnt-r{font:700 18px Consolas,'Liberation Mono',monospace;fill:var(--warn);text-anchor:middle}
.fig-cnt-l{font:18px Consolas,'Liberation Mono',monospace;fill:var(--muted);text-anchor:middle}
.fig-hole{fill:#fff;stroke:#8a99a8;stroke-width:1.5;stroke-dasharray:5 4}
.fig-cell-moved{fill:var(--accent-soft);stroke:var(--accent);stroke-width:1.5}
.fig-cell-pre{fill:var(--accent-soft);stroke:#8fb3c6;stroke-width:1.5}
.fig-key{fill:#fff8d6;stroke:var(--accent);stroke-width:2}
.fig-divider{stroke:var(--accent);stroke-width:2.5}
.fig-big-warn{font-size:22px;font-weight:700;fill:var(--warn)}
.fig-big-ok{font-size:22px;font-weight:700;fill:var(--ok)}
.fig-brace-ok{stroke:var(--ok);stroke-width:2}
.fig-brace-warn{stroke:var(--warn);stroke-width:2}
.fig-warn-b{font-size:15px;font-weight:700;fill:var(--warn)}
.fig-cell-scan{fill:#fff;stroke:#8a99a8;stroke-width:1.5}
.fig-scan-box{fill:none;stroke:var(--accent);stroke-width:1.5;stroke-dasharray:6 4}
.fig-swap{stroke:var(--warn);stroke-width:2}
.fig-axis{stroke:#8a99a8;stroke-width:1}
.fig-bar{fill:var(--accent)}
.fig-bar-lbl{font:600 14px Consolas,'Liberation Mono',monospace;fill:var(--ink)}
.fig-node-c{fill:#fff;stroke:var(--accent);stroke-width:2}
@media print{.figure svg{min-width:0}}

/* ===== Desafio hacker ===== */
.hacker{background:var(--hack-bg);color:var(--hack-ink);border:0;border-radius:8px;padding:34px clamp(20px,4vw,40px) 26px;margin:20px 0 38px;position:relative;overflow:hidden}
.hacker:before{content:"";position:absolute;inset:0 0 auto 0;height:4px;background:linear-gradient(90deg,var(--hack-accent),#4aa3df)}
.hacker h2{color:#fff;margin-bottom:10px}
.hacker h3{color:#fff;font-size:18px;margin:26px 0 10px}
.hacker .prompt-line{font:14px Consolas,monospace;color:var(--hack-accent);margin:0 0 8px}
.hacker .prompt-line:before{content:"$ "}
.hacker p,.hacker li{color:var(--hack-ink)}
.hacker ul,.hacker ol{font-size:17px}
.hacker a{color:var(--hack-accent)}
.hacker strong{color:#fff}
.hacker p code,.hacker li code,.hacker dd code{background:var(--hack-panel);color:#e8f0f5}
.hacker .meta{display:flex;flex-wrap:wrap;gap:10px;margin:0 0 22px;padding:0;list-style:none}
.hacker .meta li{font:13px Consolas,monospace;border:1px solid #2c4256;color:var(--hack-muted);padding:3px 10px;border-radius:4px}
.hacker .meta li b{color:var(--hack-accent);font-weight:600}
.hacker pre,.hacker .code-head{background:#0a1118}
.hacker .code-head{border:1px solid #22364a;border-bottom:0}
.hacker pre{border:1px solid #22364a;border-top:0}
.hacker .io{display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:14px;margin:16px 0}
.hacker .io div{background:var(--hack-panel);border-radius:5px;padding:12px 16px}
.hacker .io span{display:block;font:12px Consolas,monospace;color:var(--hack-muted);text-transform:uppercase;letter-spacing:.06em}
.hacker .io samp{white-space:pre;color:#fff;font-size:15px}
.hacker details{border-top:1px solid #22364a;margin:0}
.hacker details:last-of-type{border-bottom:1px solid #22364a}
.hacker summary{color:var(--hack-accent);font:600 15px Consolas,monospace;padding:14px 0}
.hacker summary:hover{color:#fff}
.hacker details>div{border-left:2px solid var(--hack-accent);color:var(--hack-ink);padding:6px 0 10px 20px;margin:0 0 18px}
.hacker details>div p{font-size:16px}
.hacker .table-wrap table{color:var(--hack-ink)}
.hacker .figure figcaption{color:var(--hack-muted)}
.hacker .formula{background:var(--hack-panel);color:#fff;border:1px solid #2c4256}
.hacker .figure figcaption code{background:var(--hack-panel);color:#e8f0f5}
.hacker th,.hacker td{border-color:#22364a}
.hacker thead{background:var(--hack-panel)}
.hacker :focus-visible{outline-color:var(--hack-accent)}
.hacker .code-head button{border-color:#3d566c}

/* ===== Laboratório ===== */
.array li.done{background:var(--ok-soft);color:var(--ok)}
.array li.prefix{background:var(--accent-soft)}
.array li.active{border-color:var(--accent);font-weight:bold;background:#fff8d6;color:var(--ink)}
.stats{display:flex;flex-wrap:wrap;gap:10px;margin:0 0 12px;font-size:15px}
.stats span{background:var(--soft);border-radius:4px;padding:4px 12px}
.stats b{font-family:Consolas,monospace}
.legend{display:flex;flex-wrap:wrap;gap:16px;font-size:14px;color:var(--muted);margin:14px 0 0;padding:0;list-style:none}
.legend li:before{content:"";display:inline-block;width:14px;height:14px;border-radius:3px;margin-right:6px;vertical-align:-2px;background:var(--sw)}

@media(max-width:850px){.hacker{margin-left:-6px;margin-right:-6px}.steps li{padding-left:46px}}
@media print{.hacker{background:#fff;color:#000;border:2px solid #000}.hacker *{color:#000!important}.hacker pre,.hacker .code-head{background:#f2f2f2}.hacker details:not([open])>div{display:none}.key,.pitfall,.tip{break-inside:avoid}}