:root {
  --bg: #ffffff; --bg2: #f6f8fa; --bg3: #eaeef2; --border: #d0d7de;
  --text: #1f2328; --text2: #656d76;
  --accent: #0969da; --accent2: #0550ae;
  --green: #75b287; --red: #cf222e; --orange: #9a6700; --purple: #8250df; --pink: #cf222e;
  --font-mono: 'JetBrains Mono','Fira Code',monospace;
  --font-sans: 'Inter',system-ui,sans-serif;
  --font-title: 'Syne',var(--font-sans);
  --radius: 8px; --shadow: 0 4px 24px rgba(0,0,0,.08); --nav-h: 60px;
}
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;scroll-padding-top:calc(var(--nav-h) + 16px)}
body{background:var(--bg);color:var(--text);font-family:var(--font-sans);font-size:16px;line-height:1.7;min-height:100vh}
h1,h2,h3,h4{font-family:var(--font-title);line-height:1.25}
h1{font-size:clamp(2rem,5vw,3.5rem)}
h2{font-size:clamp(1.4rem,3vw,2rem);margin:2rem 0 1rem}
h3{font-size:1.25rem;margin:1.5rem 0 .75rem;color:var(--accent2)}
h4{font-size:.9rem;color:var(--text2);text-transform:uppercase;letter-spacing:.08em;margin:1rem 0 .5rem}
p{margin-bottom:1rem}
a{color:var(--accent);text-decoration:none}
a:hover{color:var(--accent2);text-decoration:underline}
strong{color:var(--text);font-weight:700}
em{color:var(--orange);font-style:normal;font-weight:600}
code{font-family:var(--font-mono);font-size:.85em;background:#fff0f3;color:#cf222e;padding:.15em .4em;border-radius:4px;border:1px solid var(--border)}
pre{background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius);padding:1.25rem 1.5rem;overflow-x:auto;margin:1rem 0 1.5rem;position:relative}
pre code{background:none;border:none;padding:0;color:var(--text);font-size:.9rem;line-height:1.6}
::-webkit-scrollbar{width:6px;height:6px}
::-webkit-scrollbar-track{background:var(--bg2)}
::-webkit-scrollbar-thumb{background:var(--border);border-radius:3px}
nav{position:sticky;top:0;z-index:100;height:var(--nav-h);background:rgba(255,255,255,.95);backdrop-filter:blur(12px);border-bottom:1px solid var(--border);display:flex;align-items:center;padding:0 2rem;gap:2rem}
.nav-brand{font-family:var(--font-mono);font-size:1.1rem;font-weight:700;color:var(--accent);white-space:nowrap}
.nav-brand span{color:var(--green)}
.nav-links{display:flex;gap:.25rem;align-items:center;flex:1}
.nav-links a{color:var(--text2);padding:.4rem .75rem;border-radius:6px;font-size:.9rem;transition:.2s}
.nav-links a:hover,.nav-links a.active{color:var(--text);background:var(--bg3);text-decoration:none}
.nav-badge{margin-left:auto;background:var(--green);color:#000;font-size:.72rem;font-weight:700;padding:.2rem .6rem;border-radius:20px;font-family:var(--font-mono)}
.burger{display:none;background:none;border:none;color:var(--text);font-size:1.5rem;cursor:pointer;margin-left:auto}
.hero{position:relative;padding:5rem 2rem 4rem;text-align:center;overflow:hidden}
.hero-grid{position:absolute;inset:0;z-index:0;background-image:linear-gradient(rgba(9,105,218,.07) 1px,transparent 1px),linear-gradient(90deg,rgba(9,105,218,.07) 1px,transparent 1px);background-size:40px 40px;mask-image:radial-gradient(ellipse at center,black 30%,transparent 80%)}
.hero-content{position:relative;z-index:1;max-width:800px;margin:0 auto}
.hero-label{display:inline-flex;align-items:center;gap:.5rem;font-family:var(--font-mono);font-size:.8rem;color:var(--accent);border:1px solid var(--accent);padding:.3rem .8rem;border-radius:20px;margin-bottom:1.5rem}
.hero h1{margin-bottom:1rem}
.hero h1 span{color:var(--accent)}
.hero>p,.hero .hero-content>p{color:var(--text2);font-size:1.15rem;max-width:600px;margin:0 auto 2rem}
.hero-stats{display:flex;justify-content:center;gap:2rem;flex-wrap:wrap;margin:2rem 0}
.hero-stat{text-align:center}
.hero-stat-n{font-family:var(--font-mono);font-size:2rem;font-weight:700;color:var(--accent);display:block}
.hero-stat-l{font-size:.8rem;color:var(--text2)}
.hero-cta{display:flex;gap:1rem;justify-content:center;flex-wrap:wrap}
.btn{display:inline-flex;align-items:center;gap:.5rem;padding:.7rem 1.5rem;border-radius:var(--radius);font-weight:600;font-size:.95rem;cursor:pointer;transition:.2s;border:none;text-decoration:none}
.btn-primary{background:var(--accent);color:#000}
.btn-primary:hover{background:var(--accent2);color:#000;text-decoration:none}
.btn-outline{background:transparent;color:var(--text);border:1px solid var(--border)}
.btn-outline:hover{background:var(--bg3);text-decoration:none}
.chapter-layout{display:grid;grid-template-columns:220px 1fr;gap:2rem;max-width:1200px;margin:2rem auto;padding:0 1.5rem;align-items:start}
.toc{position:sticky;top:calc(var(--nav-h) + 16px);background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius);padding:1rem;max-height:calc(100vh - 100px);overflow-y:auto}
.toc h4{margin-top:0;font-size:.72rem;color:var(--text2);margin-bottom:.75rem}
.toc ul{list-style:none}
.toc li a{display:block;padding:.3rem .5rem;font-size:.82rem;color:var(--text2);border-radius:4px;transition:.15s;border-left:2px solid transparent}
.toc li a:hover,.toc li a.active{color:var(--accent);background:rgba(88,166,255,.08);border-left-color:var(--accent);text-decoration:none}
.chapter-content{min-width:0}
.chapter-header{background:linear-gradient(135deg,var(--bg2),var(--bg3));border:1px solid var(--border);border-radius:var(--radius);padding:2rem;margin-bottom:2rem;display:flex;align-items:center;gap:1.5rem}
.chapter-icon{font-size:3rem}
.chapter-header h1{font-size:clamp(1.5rem,3vw,2.2rem);margin:0 0 .5rem}
.chapter-meta{display:flex;gap:.75rem;flex-wrap:wrap}
.chapter-badge{font-family:var(--font-mono);font-size:.72rem;padding:.2rem .6rem;border-radius:4px;font-weight:600}
.badge-blue{background:rgba(88,166,255,.15);color:var(--accent);border:1px solid rgba(88,166,255,.3)}
.badge-green{background:rgba(63,185,80,.15);color:var(--green);border:1px solid rgba(63,185,80,.3)}
.badge-orange{background:rgba(210,153,34,.15);color:var(--orange);border:1px solid rgba(210,153,34,.3)}
.callout{border-radius:var(--radius);padding:1rem 1.25rem;margin:1.25rem 0;border-left:4px solid;display:flex;gap:.75rem}
.callout-icon{font-size:1.2rem;flex-shrink:0;margin-top:.1rem}
.callout-body h4{margin:0 0 .4rem;font-size:.9rem}
.callout-body p,.callout-body ul{margin:0;font-size:.9rem}
.callout-body ul{padding-left:1.25rem}
.callout-danger{background:rgba(248,81,73,.08);border-color:var(--red)}
.callout-danger .callout-icon,.callout-danger h4{color:var(--red)}
.callout-warning{background:rgba(210,153,34,.08);border-color:var(--orange)}
.callout-warning .callout-icon,.callout-warning h4{color:var(--orange)}
.callout-success{background:rgba(63,185,80,.08);border-color:var(--green)}
.callout-success .callout-icon,.callout-success h4{color:var(--green)}
.callout-info{background:rgba(88,166,255,.08);border-color:var(--accent)}
.callout-info .callout-icon,.callout-info h4{color:var(--accent)}
.callout-purple{background:rgba(188,140,255,.08);border-color:var(--purple)}
.callout-purple .callout-icon,.callout-purple h4{color:var(--purple)}
.must-know{background:linear-gradient(135deg,rgba(88,166,255,.06),rgba(63,185,80,.06));border:1px solid rgba(88,166,255,.2);border-radius:var(--radius);padding:1.25rem 1.5rem;margin:1.5rem 0}
.must-know h3{color:var(--green);margin:0 0 .75rem;font-size:1rem}
.must-know ul{list-style:none;padding:0}
.must-know li{padding:.3rem 0 .3rem 1.5rem;position:relative;font-size:.92rem}
.must-know li::before{content:'✓';position:absolute;left:0;color:var(--green);font-weight:700}
.section-card{background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius);padding:1.75rem;margin:1.5rem 0}
.section-card h2{margin-top:0}
.tabs{border:1px solid var(--border);border-radius:var(--radius);margin:1.5rem 0;overflow:hidden}
.tab-list{display:flex;background:var(--bg3);border-bottom:1px solid var(--border);overflow-x:auto}
.tab-btn{padding:.7rem 1.25rem;font-size:.875rem;font-family:var(--font-mono);background:none;border:none;color:var(--text2);cursor:pointer;border-bottom:2px solid transparent;white-space:nowrap;transition:.2s}
.tab-btn.active{color:var(--accent);border-bottom-color:var(--accent);background:var(--bg2)}
.tab-btn:hover{color:var(--text);background:var(--bg2)}
.tab-panel{display:none;padding:1.5rem}
.tab-panel.active{display:block}
.accordion{border:1px solid var(--border);border-radius:var(--radius);margin:1rem 0}
.accordion-item{border-bottom:1px solid var(--border)}
.accordion-item:last-child{border-bottom:none}
.accordion-header{width:100%;text-align:left;padding:1rem 1.25rem;background:none;border:none;color:var(--text);font-size:.95rem;font-weight:600;cursor:pointer;display:flex;justify-content:space-between;align-items:center;transition:.2s}
.accordion-header:hover{background:var(--bg3)}
.accordion-chevron{color:var(--text2);transition:transform .3s;font-style:normal}
.accordion-item.open .accordion-chevron{transform:rotate(180deg)}
.accordion-body{padding:0 1.25rem;max-height:0;overflow:hidden;transition:max-height .35s ease}
.accordion-body-inner{padding:1rem 0}
table{width:100%;border-collapse:collapse;margin:1rem 0 1.5rem;font-size:.9rem}
th{background:var(--bg3);color:var(--text);padding:.7rem 1rem;text-align:left;border:1px solid var(--border)}
td{padding:.6rem 1rem;border:1px solid var(--border);color:var(--text2)}
tr:hover td{background:rgba(255,255,255,.02)}
td:first-child{font-family:var(--font-mono);color:var(--pink)}
.exercise{border:1px solid var(--border);border-radius:var(--radius);margin:1.25rem 0;overflow:hidden}
.exercise-header{display:flex;align-items:center;gap:.75rem;padding:.9rem 1.25rem;background:var(--bg3);border-bottom:1px solid var(--border)}
.exercise-level{font-family:var(--font-mono);font-size:.72rem;font-weight:700;padding:.2rem .6rem;border-radius:4px}
.level-facile{background:rgba(63,185,80,.15);color:var(--green)}
.level-intermediaire{background:rgba(210,153,34,.15);color:var(--orange)}
.level-bac{background:rgba(248,81,73,.15);color:var(--red)}
.exercise-title{font-weight:600;font-size:.95rem}
.exercise-body{padding:1.25rem}
.exercise-body p{font-size:.9rem}
.toggle-correction{background:var(--bg3);border:1px solid var(--border);color:var(--text2);padding:.5rem 1rem;border-radius:6px;cursor:pointer;font-size:.85rem;margin-top:.75rem;transition:.2s;display:inline-flex;align-items:center;gap:.5rem}
.toggle-correction:hover{background:var(--accent);color:#000;border-color:var(--accent)}
.correction{display:none;margin-top:1rem}
.correction.visible{display:block}
.correction-box{background:rgba(63,185,80,.06);border:1px solid rgba(63,185,80,.2);border-radius:var(--radius);padding:1rem 1.25rem}
.correction-box h5{color:var(--green);font-size:.85rem;margin:0 0 .5rem}
.synthese{background:linear-gradient(135deg,var(--bg2),var(--bg3));border:1px solid var(--accent);border-radius:var(--radius);padding:1.75rem;margin:2rem 0}
.synthese h2{color:var(--accent);margin-top:0}
.synthese-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:1rem;margin-top:1rem}
.synthese-card{background:var(--bg);border:1px solid var(--border);border-radius:var(--radius);padding:1rem}
.synthese-card h4{color:var(--accent);font-size:.8rem;margin:0 0 .5rem}
.synthese-card ul{list-style:none;padding:0}
.synthese-card li{font-size:.78rem;color:var(--text2);padding:.15rem 0;font-family:var(--font-mono)}
.quiz-section{border:1px solid var(--border);border-radius:var(--radius);overflow:hidden;margin:2rem 0}
.quiz-header{background:var(--bg3);padding:1.25rem 1.5rem;border-bottom:1px solid var(--border);display:flex;justify-content:space-between;align-items:center}
.quiz-header h2{margin:0;font-size:1.2rem}
.quiz-body{padding:1.5rem}
.quiz-question{margin-bottom:2rem}
.q-text{font-size:1rem;font-weight:600;margin-bottom:1rem}
.q-opts{display:flex;flex-direction:column;gap:.5rem}
.q-opt{display:flex;align-items:flex-start;gap:.75rem;padding:.75rem 1rem;border-radius:var(--radius);border:1px solid var(--border);cursor:pointer;transition:.2s;background:var(--bg2);font-size:.9rem}
.q-opt:hover{border-color:var(--accent);background:rgba(88,166,255,.06)}
.q-opt.correct{border-color:var(--green);background:rgba(63,185,80,.1)}
.q-opt.wrong{border-color:var(--red);background:rgba(248,81,73,.1)}
.q-opt.disabled{cursor:default}
.q-opt input{margin-top:.15rem;accent-color:var(--accent);flex-shrink:0}
.q-explication{display:none;margin-top:.75rem;padding:.75rem 1rem;background:rgba(88,166,255,.06);border:1px solid rgba(88,166,255,.2);border-radius:var(--radius);font-size:.85rem;color:var(--text2)}
.q-explication.visible{display:block}
.quiz-score-box{text-align:center;padding:2rem;background:var(--bg3);border-radius:var(--radius);border:1px solid var(--border)}
.score-n{font-size:3rem;font-family:var(--font-mono);font-weight:700}
.score-n.great{color:var(--green)}.score-n.ok{color:var(--orange)}.score-n.bad{color:var(--red)}
.quiz-progress{margin-bottom:1.5rem}
.progress-bar-track{height:4px;background:var(--bg3);border-radius:2px}
.progress-bar-fill{height:100%;background:var(--accent);border-radius:2px;transition:width .3s}
.quiz-progress-text{font-size:.8rem;color:var(--text2);margin-bottom:.5rem;font-family:var(--font-mono)}
.container{max-width:1200px;margin:0 auto;padding:2rem 1.5rem}
.section-title{text-align:center;margin-bottom:2.5rem}
.section-title h2{font-size:clamp(1.5rem,3vw,2.2rem)}
.section-title p{color:var(--text2);font-size:1.05rem}
.chapters-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:1.25rem;margin-bottom:4rem}
.chapter-card{background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius);padding:1.5rem;text-decoration:none;transition:.2s;display:flex;flex-direction:column;gap:.75rem;position:relative;overflow:hidden}
.chapter-card::before{content:'';position:absolute;top:0;left:0;right:0;height:3px;background:var(--card-color,var(--accent))}
.chapter-card:hover{border-color:var(--card-color,var(--accent));background:var(--bg3);transform:translateY(-2px);box-shadow:var(--shadow);text-decoration:none}
.chapter-card-icon{font-size:2.5rem}
.chapter-card-title{font-family:var(--font-title);font-size:1.15rem;color:var(--text);font-weight:700}
.chapter-card-desc{font-size:.85rem;color:var(--text2);line-height:1.5;flex:1}
.chapter-card-footer{display:flex;gap:.5rem;flex-wrap:wrap}
.chapter-tag{font-family:var(--font-mono);font-size:.7rem;padding:.15rem .5rem;border-radius:4px;background:var(--bg3);color:var(--text2);border:1px solid var(--border)}
.features{background:var(--bg2);border-top:1px solid var(--border);border-bottom:1px solid var(--border);padding:2.5rem 1.5rem;margin:2rem 0}
.features-grid{max-width:1200px;margin:0 auto;display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:2rem;text-align:center}
.feature-icon{font-size:2rem;margin-bottom:.5rem}
.feature-title{font-weight:700;margin-bottom:.25rem}
.feature-desc{font-size:.85rem;color:var(--text2)}
.chapter-selector{display:grid;grid-template-columns:repeat(auto-fill,minmax(160px,1fr));gap:.75rem;margin:1.5rem 0}
.ch-sel-btn{background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius);padding:1rem;cursor:pointer;transition:.2s;text-align:center;color:var(--text)}
.ch-sel-btn:hover{border-color:var(--accent)}
.ch-sel-btn.selected{border-color:var(--accent);background:rgba(88,166,255,.1)}
.ch-sel-btn .cs-icon{font-size:1.75rem;display:block;margin-bottom:.35rem}
.ch-sel-btn .cs-name{font-size:.8rem;font-weight:600}
.quiz-config{background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius);padding:1.5rem;margin:1.5rem 0}
.quiz-config label{display:block;color:var(--text2);font-size:.85rem;margin-bottom:.4rem}
.quiz-config select{background:var(--bg3);border:1px solid var(--border);color:var(--text);padding:.6rem .9rem;border-radius:6px;font-size:.9rem;width:100%;max-width:300px}
footer{border-top:1px solid var(--border);padding:2rem 1.5rem;text-align:center;color:var(--text2);font-size:.85rem;margin-top:4rem}
footer a{color:var(--text2)}
.kw{color:#ff7b72}.fn{color:#d2a8ff}.str{color:#a5d6ff}.cm{color:#8b949e;font-style:italic}.num{color:#79c0ff}
@media(max-width:900px){.chapter-layout{grid-template-columns:1fr}.toc{display:none}}
@media(max-width:640px){nav{padding:0 1rem;gap:1rem}.nav-links{display:none;flex-direction:column;position:fixed;top:var(--nav-h);left:0;right:0;background:var(--bg2);border-bottom:1px solid var(--border);padding:1rem;gap:.25rem;z-index:99}.nav-links.open{display:flex}.burger{display:block}.nav-badge{display:none}.hero{padding:3rem 1rem 2rem}.container,.chapter-layout{padding:1rem}.chapter-header{flex-direction:column;text-align:center}}