/* ─── mondialisation.css — Thème : Réseau mondial, bleu électrique ──────────── */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@200;300;400;500;600;700&family=Merriweather:ital,wght@0,300;0,400;1,300;1,400&family=Fira+Code:wght@400;500&display=swap');

:root {
  --void:#020912; --deep:#04111e; --surface:#061828; --surface-2:#08223a;
  --electric:#0ea5e9; --el-2:#38bdf8; --el-glow:rgba(14,165,233,.2);
  --el-pale:rgba(14,165,233,.07); --el-mid:rgba(14,165,233,.3);
  --ink:#d8effc; --ink-mid:#6a9fbc; --ink-dim:#2a5070;
  --border:rgba(14,165,233,.14); --border-hi:rgba(14,165,233,.4);
  --violet:#8b5cf6; --vi-pale:rgba(139,92,246,.08);
  --amber:#f59e0b; --amber-pale:rgba(245,158,11,.08);
  --green:#10b981; --green-pale:rgba(16,185,129,.08);
  --red:#f43f5e; --red-pale:rgba(244,63,94,.08);
  --font-display:'Inter',sans-serif;
  --font-body:'Merriweather',Georgia,serif;
  --font-mono:'Fira Code',monospace;
  --sidebar-w:265px; --radius:6px;
}
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0;}
html{scroll-behavior:smooth;}

body{
  font-family:var(--font-body);background:var(--void);color:var(--ink);font-size:16.5px;line-height:1.8;
  background-image:
    radial-gradient(ellipse at 50% 0%, rgba(14,165,233,.08) 0,transparent 60%),
    radial-gradient(circle at 10% 80%, rgba(139,92,246,.05) 0,transparent 40%),
    /* Network grid */
    linear-gradient(rgba(14,165,233,.03) 1px,transparent 1px),
    linear-gradient(90deg,rgba(14,165,233,.03) 1px,transparent 1px);
  background-size:100% 100%,100% 100%,50px 50px,50px 50px;
  background-attachment:fixed;
}

.progress-bar{position:fixed;top:0;left:0;height:2px;width:0%;background:linear-gradient(90deg,var(--electric),var(--el-2),var(--violet));z-index:200;transition:width .08s linear;box-shadow:0 0 8px var(--el-glow);}

.page-layout{display:flex;min-height:100vh;}

.sidebar{width:var(--sidebar-w);flex-shrink:0;background:var(--deep);border-right:1px solid var(--border);position:sticky;top:0;height:100vh;overflow-y:auto;display:flex;flex-direction:column;scrollbar-width:thin;scrollbar-color:var(--surface-2) transparent;}
.sidebar-header{padding:26px 22px 20px;border-bottom:1px solid var(--border);}
.sidebar-site-link{font-family:var(--font-mono);font-size:.6rem;letter-spacing:.15em;color:var(--ink-dim);text-decoration:none;display:block;margin-bottom:12px;}
.sidebar-title{font-family:var(--font-display);font-size:1.2rem;font-weight:700;color:var(--electric);letter-spacing:-.01em;}
.toc-nav{padding:12px 0 16px;flex:1;}
.toc-section-label{font-family:var(--font-mono);font-size:.58rem;letter-spacing:.2em;text-transform:uppercase;color:var(--ink-dim);padding:10px 22px 4px;}
.toc-link{display:block;padding:5px 22px 5px 26px;font-family:var(--font-display);font-size:.82rem;font-weight:300;color:var(--ink-mid);text-decoration:none;border-left:2px solid transparent;transition:all .15s;}
.toc-link:hover,.toc-link.active{color:var(--electric);border-left-color:var(--electric);background:var(--el-pale);}
.toc-link.active{color:var(--el-2);}
.sidebar-subject-nav{padding:14px 22px;border-top:1px solid var(--border);}
.sidebar-subject-nav p{font-family:var(--font-mono);font-size:.58rem;letter-spacing:.18em;text-transform:uppercase;color:var(--ink-dim);margin-bottom:8px;}
.sidebar-subject-nav a{display:block;font-family:var(--font-display);font-size:.8rem;font-weight:300;color:var(--ink-dim);text-decoration:none;padding:3px 0;transition:color .15s;}
.sidebar-subject-nav a:hover{color:var(--electric);}
.sidebar-subject-nav a.current{color:var(--electric);font-weight:600;}

.main{flex:1;min-width:0;padding:0 58px 100px;max-width:840px;}

.page-header{padding:56px 0 38px;margin-bottom:50px;border-bottom:1px solid var(--border);position:relative;}
.page-header::after{content:'';position:absolute;bottom:0;left:0;right:0;height:1px;background:linear-gradient(90deg,var(--electric),var(--violet),transparent);box-shadow:0 0 10px var(--el-glow);}
.subject-tag{font-family:var(--font-mono);font-size:.62rem;letter-spacing:.22em;text-transform:uppercase;color:var(--electric);margin-bottom:12px;}
h1.page-title{font-family:var(--font-display);font-size:3.2rem;font-weight:700;color:var(--ink);line-height:1.0;letter-spacing:-.03em;text-shadow:0 0 30px var(--el-glow);}
.page-intro{margin-top:16px;font-size:1rem;color:var(--ink-mid);font-style:italic;max-width:540px;font-family:var(--font-body);}

.section{margin-bottom:60px;scroll-margin-top:28px;}
h2.section-title{font-family:var(--font-display);font-size:1.45rem;font-weight:700;color:var(--ink);margin-bottom:20px;padding-bottom:10px;border-bottom:1px solid var(--border);display:flex;align-items:center;gap:12px;letter-spacing:-.02em;}
h2.section-title .num{font-family:var(--font-mono);font-size:.7rem;color:var(--void);background:var(--electric);padding:3px 9px;border-radius:20px;font-weight:400;box-shadow:0 0 6px var(--el-glow);}
h3.sub-title{font-family:var(--font-display);font-size:1rem;font-weight:600;color:var(--electric);margin:28px 0 12px;letter-spacing:-.01em;}
p{margin-bottom:.9em;}ul,ol{padding-left:1.4em;margin-bottom:.9em;}li{margin-bottom:.28em;}

.box{padding:16px 20px 14px;margin:18px 0;border-radius:var(--radius);border:1px solid var(--border);background:var(--surface);}
.box-label{font-family:var(--font-mono);font-size:.62rem;font-weight:500;letter-spacing:.15em;text-transform:uppercase;display:block;margin-bottom:8px;}
.box.def{background:var(--el-pale);border-color:var(--border-hi);}
.box.def .box-label{color:var(--electric);}
.box.theorem{background:var(--vi-pale);border-color:rgba(139,92,246,.3);}
.box.theorem .box-label{color:var(--violet);}
.box.prop{background:var(--amber-pale);border-color:rgba(245,158,11,.25);}
.box.prop .box-label{color:var(--amber);}
.box.corollary{background:var(--green-pale);border-color:rgba(16,185,129,.25);}
.box.corollary .box-label{color:var(--green);}
.box.example{background:var(--red-pale);border-color:rgba(244,63,94,.2);}
.box.example .box-label{color:var(--red);}
.box.remark{background:var(--surface-2);border-color:var(--border);}
.box.remark .box-label{color:var(--ink-mid);}

.proof-toggle{display:inline-flex;align-items:center;gap:6px;font-family:var(--font-mono);font-size:.7rem;letter-spacing:.08em;color:var(--electric);border:1px solid var(--border-hi);padding:5px 14px;border-radius:20px;cursor:pointer;background:transparent;margin-top:8px;transition:all .18s;user-select:none;}
.proof-toggle:hover{background:var(--electric);color:var(--void);box-shadow:0 0 10px var(--el-glow);}
.proof-toggle .arrow{transition:transform .2s;}
.proof-toggle.open .arrow{transform:rotate(90deg);}
.proof-content{max-height:0;overflow:hidden;transition:max-height .3s ease;}
.proof-content.open{max-height:900px;}
.proof-inner{margin-top:12px;padding:14px 18px;background:var(--surface-2);border:1px dashed var(--border);border-radius:var(--radius);color:var(--ink-mid);font-size:.93rem;font-style:italic;}
.qed{float:right;color:var(--electric);font-family:var(--font-mono);font-size:.82rem;font-style:normal;}

.formula-block{text-align:center;padding:20px 16px;margin:16px 0;background:var(--void);border:1px solid var(--border);border-radius:var(--radius);overflow-x:auto;box-shadow:0 0 16px rgba(14,165,233,.04);}

.math-table{width:100%;border-collapse:collapse;margin:16px 0;font-size:.9rem;border-radius:var(--radius);overflow:hidden;border:1px solid var(--border);}
.math-table th{background:var(--surface-2);color:var(--electric);padding:10px 14px;text-align:left;font-family:var(--font-mono);font-size:.7rem;letter-spacing:.12em;text-transform:uppercase;border-bottom:1px solid var(--border-hi);}
.math-table td{padding:9px 14px;border-bottom:1px solid var(--border);vertical-align:top;}
.math-table tr:hover td{background:var(--el-pale);}
.math-table td:first-child{font-family:var(--font-mono);font-size:.8rem;color:var(--electric);}
code{font-family:var(--font-mono);font-size:.82em;background:var(--surface-2);color:var(--el-2);padding:2px 6px;border-radius:4px;border:1px solid var(--border);}
.two-col{display:grid;grid-template-columns:1fr 1fr;gap:14px;margin:14px 0;}
.two-col .box{margin:0;}

.mobile-header{display:none;position:sticky;top:0;z-index:50;background:var(--deep);border-bottom:1px solid var(--border);padding:12px 18px;align-items:center;justify-content:space-between;}
.mobile-menu-btn{background:none;border:none;color:var(--electric);font-size:1.3rem;cursor:pointer;}
.mobile-title{font-family:var(--font-display);font-size:1rem;font-weight:700;color:var(--electric);letter-spacing:-.02em;}
.mobile-drawer{display:none;position:fixed;inset:0;z-index:100;}
.mobile-drawer.open{display:flex;}
.drawer-overlay{position:absolute;inset:0;background:rgba(0,0,0,.75);}
.drawer-panel{position:relative;z-index:1;width:265px;background:var(--deep);height:100%;overflow-y:auto;padding:16px 0;border-right:1px solid var(--border);}
@media(max-width:960px){.sidebar{display:none;}.mobile-header{display:flex;}.main{padding:0 20px 70px;}h1.page-title{font-size:2.3rem;}.two-col{grid-template-columns:1fr;}}