:root{--color-bg-primary: #05070A;--color-bg-secondary: #0D1117;--color-bg-tertiary: #161B22;--color-bg-card: rgba(22, 27, 34, .7);--color-bg-code: #010409;--color-bg-inline-code: rgba(247, 147, 26, .12);--color-bg-hover: rgba(247, 147, 26, .08);--color-border: rgba(48, 54, 61, .6);--color-border-light: rgba(48, 54, 61, .3);--color-text-primary: #F0F6FC;--color-text-secondary: #8B949E;--color-text-tertiary: #6E767E;--color-text-link: #F7931A;--color-bitcoin: #F7931A;--color-bitcoin-dark: #D47600;--color-bitcoin-glow: rgba(247, 147, 26, .3);--color-bitcoin-gradient: linear-gradient(135deg, #F7931A 0%, #FFAB40 100%);--color-accent-blue: #58A6FF;--color-accent-green: #3FB950;--color-accent-purple: #BC8CFF;--color-accent-red: #F85149;--color-accent-cyan: #39D2C0;--glass-bg: rgba(13, 17, 23, .8);--glass-border: rgba(255, 255, 255, .1);--glass-blur: blur(12px);--glass-shadow: 0 8px 32px 0 rgba(0, 0, 0, .37);--font-body: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;--font-mono: "JetBrains Mono", "Fira Code", "Cascadia Code", monospace;--text-xs: .75rem;--text-sm: .875rem;--text-base: 1rem;--text-lg: 1.125rem;--text-xl: 1.25rem;--text-2xl: 1.5rem;--text-3xl: 2rem;--text-4xl: 2.75rem;--text-5xl: 3.5rem;--line-height-tight: 1.2;--line-height-normal: 1.6;--line-height-relaxed: 1.8;--space-1: .25rem;--space-2: .5rem;--space-3: .75rem;--space-4: 1rem;--space-5: 1.25rem;--space-6: 1.5rem;--space-8: 2rem;--space-10: 2.5rem;--space-12: 3rem;--space-16: 4rem;--sidebar-width: 300px;--content-max-width: 860px;--radius-sm: 6px;--radius-md: 10px;--radius-lg: 14px;--radius-xl: 20px;--shadow-sm: 0 1px 2px rgba(0, 0, 0, .5);--shadow-md: 0 4px 20px rgba(0, 0, 0, .6);--shadow-lg: 0 12px 40px rgba(0, 0, 0, .7);--shadow-glow: 0 0 25px var(--color-bitcoin-glow);--transition-fast: .15s cubic-bezier(.4, 0, .2, 1);--transition-normal: .3s cubic-bezier(.4, 0, .2, 1);--transition-slow: .5s cubic-bezier(.4, 0, .2, 1)}*,*:before,*:after{box-sizing:border-box;margin:0;padding:0}html{scroll-behavior:smooth;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}body{font-family:var(--font-body);font-size:var(--text-base);line-height:1.7;color:var(--color-text-primary);background:var(--color-bg-primary);overflow-x:hidden}::selection{background:#f7931a4d;color:#fff}.app-layout{display:flex;min-height:100vh}.sidebar{position:fixed;top:0;left:0;bottom:0;width:var(--sidebar-width);background:var(--glass-bg);backdrop-filter:var(--glass-blur);-webkit-backdrop-filter:var(--glass-blur);border-right:1px solid var(--glass-border);overflow-y:auto;z-index:100;display:flex;flex-direction:column;transition:transform var(--transition-normal);box-shadow:var(--glass-shadow)}.sidebar-header{padding:var(--space-8) var(--space-6);flex-shrink:0;background:linear-gradient(to 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var(--space-5);font-size:var(--text-xs);font-weight:600;text-transform:uppercase;letter-spacing:.08em;color:var(--color-text-tertiary);margin-top:var(--space-4)}.nav-section-label:first-child{margin-top:0}.nav-link{display:flex;align-items:center;gap:var(--space-4);padding:var(--space-3) var(--space-6);color:var(--color-text-secondary);text-decoration:none;font-size:var(--text-sm);font-weight:500;transition:all var(--transition-normal);line-height:1.4;margin:2px var(--space-3);border-radius:var(--radius-md)}.nav-link:hover{color:var(--color-text-primary);background:#ffffff0d;transform:translate(4px)}.nav-link.active{color:var(--color-bitcoin);background:#f7931a1a;font-weight:600;box-shadow:inset 0 0 0 1px #f7931a33}.nav-link .nav-number{font-size:var(--text-xs);color:var(--color-text-tertiary);min-width:24px;font-weight:600;font-family:var(--font-mono);opacity:.7}.nav-link.active .nav-number{color:var(--color-bitcoin);opacity:1}.sidebar-footer{padding:var(--space-6) 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var(--space-8)}.mobile-header{display:none;position:fixed;top:0;left:0;right:0;height:56px;background:var(--color-bg-secondary);border-bottom:1px solid var(--color-border);z-index:90;align-items:center;padding:0 var(--space-4)}.menu-toggle{background:none;border:none;color:var(--color-text-primary);font-size:var(--text-xl);cursor:pointer;padding:var(--space-2);display:flex;align-items:center;justify-content:center;width:40px;height:40px;border-radius:var(--radius-md);transition:background var(--transition-fast)}.menu-toggle:hover{background:var(--color-bg-hover)}.mobile-title{font-size:var(--text-sm);font-weight:600;margin-left:var(--space-3);color:var(--color-text-primary)}.sidebar-overlay{display:none;position:fixed;top:0;right:0;bottom:0;left:0;background:#0009;z-index:99}.chapter-header{margin-bottom:var(--space-12);padding-bottom:var(--space-10);border-bottom:1px solid var(--color-border);position:relative}.chapter-header:after{content:"";position:absolute;bottom:-1px;left:0;width:100px;height:3px;background:var(--color-bitcoin-gradient);border-radius:3px}.chapter-number{font-size:var(--text-xs);font-weight:700;color:var(--color-bitcoin);text-transform:uppercase;letter-spacing:.2em;margin-bottom:var(--space-4);font-family:var(--font-mono);display:inline-block;padding:var(--space-1) var(--space-3);background:#f7931a1a;border-radius:20px}h1{font-size:var(--text-4xl);font-weight:800;letter-spacing:-.04em;line-height:var(--line-height-tight);color:var(--color-text-primary);margin-bottom:var(--space-4)}h2{font-size:var(--text-2xl);font-weight:700;letter-spacing:-.02em;line-height:var(--line-height-tight);color:var(--color-text-primary);margin-top:var(--space-16);margin-bottom:var(--space-8);padding-bottom:var(--space-3);border-bottom:2px solid var(--color-border-light)}h3{font-size:var(--text-xl);font-weight:700;letter-spacing:-.01em;color:var(--color-text-primary);margin-top:var(--space-12);margin-bottom:var(--space-6)}h4{font-size:var(--text-lg);font-weight:600;color:var(--color-text-primary);margin-top:var(--space-8);margin-bottom:var(--space-4)}p{margin-bottom:var(--space-6);color:var(--color-text-primary);line-height:var(--line-height-relaxed);opacity:.92}a{color:var(--color-text-link);text-decoration:none;transition:all var(--transition-fast);font-weight:500;border-bottom:1px solid 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.hljs-params{color:var(--color-text-primary)}.code-block-body .hljs-variable{color:#ffa657}.code-block-body .hljs-literal{color:#7ee787}.code-block-body .hljs-meta{color:#8b949e}.code-block-body .hljs-attr{color:#79c0ff}.code-block-body .hljs-selector-class{color:#d2a8ff}.code-block-body .hljs-property{color:#79c0ff}.callout{margin:var(--space-8) 0;padding:var(--space-6);border-radius:var(--radius-lg);border:1px solid var(--color-border);background:var(--color-bg-card);box-shadow:var(--shadow-sm)}.callout-header{display:flex;align-items:center;gap:var(--space-3);font-weight:700;font-size:var(--text-xs);text-transform:uppercase;letter-spacing:.1em;margin-bottom:var(--space-4)}.callout-body p:last-child{margin-bottom:0}.callout.note{border-top:4px solid var(--color-accent-blue);background:linear-gradient(180deg,rgba(88,166,255,.05) 0%,transparent 100%)}.callout.note .callout-header{color:var(--color-accent-blue)}.callout.summary{border-top:4px solid var(--color-accent-purple);background:linear-gradient(180deg,rgba(188,140,255,.05) 0%,transparent 100%)}.callout.summary .callout-header{color:var(--color-accent-purple)}.callout.exercise{border-top:4px solid var(--color-accent-green);background:linear-gradient(180deg,rgba(63,185,80,.05) 0%,transparent 100%)}.callout.exercise .callout-header{color:var(--color-accent-green)}.callout.emphbox{border-left:4px solid var(--color-bitcoin);background:var(--color-bg-code);padding:var(--space-6);box-shadow:var(--shadow-glow)}.callout.emphbox pre{margin:0;font-family:var(--font-mono);font-size:var(--text-sm);line-height:var(--line-height-relaxed);white-space:pre-wrap;color:var(--color-text-primary)}.table-wrapper{margin:var(--space-8) 0;overflow-x:auto;border-radius:var(--radius-lg);border:1px solid var(--color-border);background:var(--color-bg-secondary);box-shadow:var(--shadow-sm)}table{width:100%;border-collapse:collapse;font-size:var(--text-sm)}thead{background:#ffffff08}th{padding:var(--space-4) var(--space-5);text-align:left;font-weight:700;color:var(--color-text-primary);border-bottom:1px solid var(--color-border);white-space:nowrap;letter-spacing:.02em}td{padding:var(--space-4) var(--space-5);border-bottom:1px solid var(--color-border-light);color:var(--color-text-secondary);line-height:1.5}tr:last-child td{border-bottom:none}tr:hover td{background:#f7931a08;color:var(--color-text-primary)}.figure{margin:var(--space-8) 0;text-align:center}.figure img{max-width:100%;height:auto;border-radius:var(--radius-md);border:1px solid var(--color-border)}.figure-caption{margin-top:var(--space-3);font-size:var(--text-sm);color:var(--color-text-secondary);font-style:italic}.stack-visualizer{margin:var(--space-10) 0;border:1px solid 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var(--space-4);background:#f7931a1a;border:1px solid rgba(247,147,26,.3);border-radius:var(--radius-md);color:var(--color-bitcoin);font-weight:600;box-shadow:inset 0 0 10px #f7931a0d;animation:stackPush .4s cubic-bezier(.34,1.56,.64,1)}@keyframes stackPush{0%{opacity:0;transform:scale(.9) translateY(20px)}to{opacity:1;transform:scale(1) translateY(0)}}.stack-empty{font-size:var(--text-sm);color:var(--color-text-tertiary);font-style:italic;display:flex;align-items:center;justify-content:center;height:100%}.stack-explanation-panel{padding:var(--space-4) var(--space-6);background:#f7931a0d;border-top:1px solid var(--color-border);font-size:var(--text-sm);color:var(--color-text-secondary);line-height:1.6;font-weight:500}@media(max-width:1100px){.sidebar{transform:translate(-100%)}.sidebar.open{transform:translate(0)}.sidebar-overlay.visible{display:block}.mobile-header{display:flex;background:var(--glass-bg);backdrop-filter:var(--glass-blur);-webkit-backdrop-filter:var(--glass-blur);border-bottom:1px solid var(--glass-border)}.main-content{margin-left:0;padding-top:56px}}.chapter-nav{display:flex;justify-content:space-between;align-items:stretch;gap:var(--space-6);margin-top:var(--space-16);padding-top:var(--space-8);border-top:1px solid var(--color-border)}.chapter-nav-link{display:flex;flex-direction:column;gap:var(--space-1);padding:var(--space-4) var(--space-5);background:var(--color-bg-secondary);border:1px solid var(--color-border);border-radius:var(--radius-lg);text-decoration:none;transition:all .2s 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