:root{--bg-0: #0a0d13;--bg-1: #0e121a;--bg-2: #141a25;--bg-3: #1b2230;--bg-hover: #222b3b;--fg-0: #eef2f8;--fg-1: #c2cbd9;--fg-2: #8a96a8;--fg-3: #5b6678;--rust: #dea584;--rust-deep: #c97e54;--rust-soft: rgba(222, 165, 132, .12);--js: #f0db4f;--js-soft: rgba(240, 219, 79, .12);--ok: #5ad19a;--ok-soft: rgba(90, 209, 154, .12);--warn: #f2b347;--warn-soft: rgba(242, 179, 71, .12);--err: #ef6f6f;--err-soft: rgba(239, 111, 111, .12);--info: #6aa6ff;--info-soft: rgba(106, 166, 255, .12);--line: rgba(255, 255, 255, .08);--line-strong: rgba(255, 255, 255, .16);--font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;--font-mono: "JetBrains Mono", "SF Mono", "Fira Code", ui-monospace, "Cascadia Code", Consolas, monospace;--radius-sm: 6px;--radius: 10px;--radius-lg: 16px;--shadow: 0 8px 30px rgba(0, 0, 0, .4);--shadow-lg: 0 20px 60px rgba(0, 0, 0, .55);--code-bg: #1a1f2b;--code-output-bg: #11151d;--err-term-bg: #1a1015;--err-term-fg: #f0b8b8;--topbar-bg: rgba(10, 13, 19, .8);--selection-fg: #fff;--page-bg: radial-gradient(1200px 800px at 80% -10%, rgba(222, 165, 132, .06), transparent 60%), radial-gradient(1000px 700px at -10% 10%, rgba(106, 166, 255, .05), transparent 55%), var(--bg-0);--sidebar-w: 300px;--content-max: 880px;color-scheme:dark}:root[data-theme=light]{--bg-0: #f7f4ee;--bg-1: #ffffff;--bg-2: #f1ece3;--bg-3: #e7e0d4;--bg-hover: #ded5c6;--fg-0: #1d1a15;--fg-1: #3c382f;--fg-2: #6b6456;--fg-3: #9b9384;--rust: #b1623a;--rust-deep: #8f4a27;--rust-soft: rgba(177, 98, 58, .1);--js: #9a7b00;--js-soft: rgba(154, 123, 0, .12);--ok: #1f9d63;--ok-soft: rgba(31, 157, 99, .12);--warn: #b9791a;--warn-soft: rgba(185, 121, 26, .14);--err: #cf4848;--err-soft: rgba(207, 72, 72, .1);--info: #2f6fd6;--info-soft: rgba(47, 111, 214, .1);--line: rgba(40, 30, 20, .1);--line-strong: rgba(40, 30, 20, .2);--shadow: 0 6px 22px rgba(60, 45, 30, .12);--shadow-lg: 0 18px 50px rgba(60, 45, 30, .18);--code-bg: #f6f2ea;--code-output-bg: #efe9df;--err-term-bg: #fbeaea;--err-term-fg: #9c3a3a;--topbar-bg: rgba(247, 244, 238, .82);--selection-fg: #1d1a15;--page-bg: radial-gradient(1200px 800px at 80% -10%, rgba(177, 98, 58, .07), transparent 60%), radial-gradient(1000px 700px at -10% 10%, rgba(47, 111, 214, .05), transparent 55%), var(--bg-0);color-scheme:light}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;font-family:var(--font-sans);background:var(--page-bg);background-attachment:fixed;color:var(--fg-1);transition:background-color .25s ease,color .25s ease;-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility;line-height:1.7}a{color:var(--rust);text-decoration:none}a:hover{text-decoration:underline}h1,h2,h3,h4{color:var(--fg-0);line-height:1.3;font-weight:700}::selection{background:var(--rust-soft);color:var(--selection-fg)}::-webkit-scrollbar{width:10px;height:10px}::-webkit-scrollbar-thumb{background:var(--bg-3);border-radius:8px;border:2px solid var(--bg-0)}::-webkit-scrollbar-thumb:hover{background:var(--bg-hover)}.prose p{margin:.9em 0;color:var(--fg-1)}.prose h2{font-size:1.6rem;margin:2.2rem 0 1rem;padding-top:.4rem;scroll-margin-top:84px}.prose h3{font-size:1.22rem;margin:1.8rem 0 .8rem;color:var(--fg-0);scroll-margin-top:84px}.prose ul,.prose ol{padding-left:1.4em;color:var(--fg-1)}.prose li{margin:.4em 0}.prose strong{color:var(--fg-0)}.prose code:not(pre code){font-family:var(--font-mono);font-size:.86em;background:var(--bg-2);border:1px solid var(--line);padding:.1em .42em;border-radius:5px;color:var(--rust)}.prose hr{border:none;border-top:1px solid var(--line);margin:2.4rem 0}.prose blockquote{margin:1.2rem 0;padding:.4rem 1.1rem;border-left:3px solid var(--rust-deep);background:var(--rust-soft);border-radius:0 var(--radius-sm) var(--radius-sm) 0;color:var(--fg-1)}.kbd{font-family:var(--font-mono);font-size:.78em;background:var(--bg-3);border:1px solid var(--line-strong);border-bottom-width:2px;border-radius:5px;padding:.1em .45em;color:var(--fg-1)}@media (max-width: 900px){:root{--sidebar-w: 0px}}.layout{min-height:100vh}.topbar{position:sticky;top:0;z-index:50;height:60px;display:flex;align-items:center;gap:16px;padding:0 20px;background:var(--topbar-bg);backdrop-filter:blur(14px);border-bottom:1px solid var(--line)}.brand{display:flex;align-items:center;gap:10px;color:var(--fg-0);font-weight:800;font-size:1.05rem;letter-spacing:.2px}.brand:hover{text-decoration:none}.brand-mark{font-size:1.4rem}.brand-text em{color:var(--rust);font-style:normal;font-weight:600}.topbar-social{display:flex;align-items:center;gap:4px;margin-left:4px;padding-left:12px;border-left:1px solid var(--line)}.social-link{display:grid;place-items:center;width:32px;height:32px;border-radius:8px;color:var(--fg-2);transition:color .15s,background .15s}.social-link:hover{color:var(--fg-0);background:var(--bg-2);text-decoration:none}.topbar-progress{margin-left:auto;position:relative;width:180px;height:8px;background:var(--bg-3);border-radius:99px;overflow:hidden}.topbar-progress-bar{height:100%;background:linear-gradient(90deg,var(--rust-deep),var(--rust));transition:width .4s ease}.topbar-progress-label{position:absolute;top:-22px;right:0;font-size:.72rem;color:var(--fg-2);font-variant-numeric:tabular-nums}.topbar-link{font-size:.85rem;color:var(--fg-2);white-space:nowrap}.topbar-link:hover{color:var(--rust);text-decoration:none}.lang-toggle{display:inline-flex;align-items:center;gap:5px;font-size:.82rem;font-weight:600;color:var(--fg-2);background:var(--bg-2);border:1px solid var(--line);border-radius:8px;padding:5px 10px;cursor:pointer;white-space:nowrap;transition:color .15s,background .15s,border-color .15s}.lang-toggle:hover{color:var(--rust);border-color:var(--rust)}.lang-toggle-ico{font-size:.95rem;line-height:1}.theme-toggle{display:inline-flex;align-items:center;justify-content:center;color:var(--fg-2);background:var(--bg-2);border:1px solid var(--line);border-radius:8px;padding:5px 8px;cursor:pointer;transition:color .15s,background .15s,border-color .15s}.theme-toggle:hover{color:var(--rust);border-color:var(--rust)}.theme-toggle-ico{font-size:1rem;line-height:1}.hamburger{display:none;flex-direction:column;gap:4px;background:none;border:none;cursor:pointer;padding:6px}.hamburger span{width:20px;height:2px;background:var(--fg-1);border-radius:2px}.body{display:grid;grid-template-columns:var(--sidebar-w) 1fr}.sidebar{position:sticky;top:60px;align-self:start;height:calc(100vh - 60px);overflow-y:auto;border-right:1px solid var(--line);padding:18px 12px 24px;display:flex;flex-direction:column}.nav{flex:1}.nav-home{display:block;padding:9px 12px;border-radius:var(--radius-sm);color:var(--fg-1);font-size:.9rem;margin-bottom:8px}.nav-home:hover{background:var(--bg-2);text-decoration:none}.nav-group{margin-top:14px}.nav-group-title{font-size:.72rem;text-transform:uppercase;letter-spacing:.12em;color:var(--fg-3);padding:6px 12px;font-weight:700}.nav-item{display:flex;align-items:flex-start;gap:10px;padding:8px 12px;border-radius:var(--radius-sm);color:var(--fg-1);font-size:.9rem;line-height:1.4;transition:background .15s}.nav-item:hover{background:var(--bg-2);text-decoration:none}.nav-item.active{background:var(--rust-soft);color:var(--fg-0)}.nav-item.active .nav-num{color:var(--rust);border-color:var(--rust-deep)}.nav-num{flex-shrink:0;width:24px;height:22px;display:grid;place-items:center;font-family:var(--font-mono);font-size:.72rem;color:var(--fg-3);border:1px solid var(--line);border-radius:6px;margin-top:1px}.nav-label{display:flex;gap:6px}.nav-icon{opacity:.9}.sidebar-foot{font-size:.74rem;color:var(--fg-3);padding:14px 12px 0;border-top:1px solid var(--line);margin-top:12px}.content{min-width:0;padding:40px clamp(20px,5vw,64px) 120px;animation:fade-in .4s ease}@keyframes fade-in{0%{opacity:0;transform:translateY(8px)}to{opacity:1;transform:none}}.scrim{display:none}@media (max-width: 640px){.topbar-social{display:none}}@media (max-width: 900px){.hamburger{display:flex}.topbar-link{display:none}.topbar-progress{width:90px}.body{grid-template-columns:1fr}.sidebar{position:fixed;top:60px;left:0;width:290px;background:var(--bg-1);transform:translate(-100%);transition:transform .25s ease;z-index:40}.sidebar.open{transform:none;box-shadow:var(--shadow-lg)}.scrim{display:block;position:fixed;inset:60px 0 0;background:#00000080;z-index:30}}.home{max-width:980px;margin:0 auto}.hero{text-align:center;padding:30px 0 50px}.hero-badges{display:flex;gap:10px;justify-content:center;flex-wrap:wrap;margin-bottom:24px}.hero-badge{font-size:.78rem;color:var(--fg-2);border:1px solid var(--line);background:var(--bg-1);padding:4px 12px;border-radius:99px}.hero-title{font-size:clamp(2.2rem,6vw,3.6rem);line-height:1.15;margin:0 0 18px;letter-spacing:-.02em}.hero-title em{font-style:normal;background:linear-gradient(120deg,var(--rust),#f0c9a8);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent}.hero-sub{max-width:660px;margin:0 auto 28px;font-size:1.06rem;color:var(--fg-2)}.hero-sub code{font-family:var(--font-mono);font-size:.88em;color:var(--rust);background:var(--bg-2);padding:.1em .4em;border-radius:5px}.hero-actions{display:flex;gap:14px;justify-content:center;flex-wrap:wrap}.btn-primary{background:linear-gradient(120deg,var(--rust-deep),var(--rust));color:#1a1209;font-weight:700;padding:13px 26px;border-radius:99px;font-size:.98rem;box-shadow:0 8px 24px #dea58440;transition:transform .18s,box-shadow .18s}.btn-primary:hover{text-decoration:none;transform:translateY(-2px);box-shadow:0 12px 30px #dea58459}.btn-ghost{border:1px solid var(--line-strong);color:var(--fg-1);padding:13px 24px;border-radius:99px;font-size:.98rem}.btn-ghost:hover{text-decoration:none;background:var(--bg-2);border-color:var(--rust-deep)}.hero-stats{display:flex;gap:40px;justify-content:center;margin-top:40px}.hero-stats div{display:flex;flex-direction:column}.hero-stats strong{font-size:1.8rem;color:var(--rust);font-variant-numeric:tabular-nums}.hero-stats span{font-size:.8rem;color:var(--fg-3)}.why-cards{display:grid;grid-template-columns:repeat(3,1fr);gap:16px;margin:20px 0 60px}.why-card{border:1px solid var(--line);border-radius:var(--radius-lg);background:var(--bg-1);padding:22px}.why-ico{font-size:1.6rem}.why-card h3{margin:12px 0 8px;font-size:1.05rem}.why-card p{margin:0;color:var(--fg-2);font-size:.92rem}.outline-title{font-size:1.5rem;margin-bottom:20px;text-align:center}.outline-group{margin-bottom:28px}.outline-group-name{font-size:.76rem;text-transform:uppercase;letter-spacing:.12em;color:var(--rust);font-weight:700;margin-bottom:10px}.outline-list{display:flex;flex-direction:column;gap:8px}.outline-item{display:flex;align-items:center;gap:14px;padding:14px 16px;border:1px solid var(--line);border-radius:var(--radius);background:var(--bg-1);transition:all .16s}.outline-item:hover{text-decoration:none;border-color:var(--rust-deep);transform:translate(4px);background:var(--bg-2)}.outline-item.is-done{border-color:#5ad19a66}.outline-num{flex-shrink:0;width:30px;height:30px;display:grid;place-items:center;font-family:var(--font-mono);font-size:.82rem;color:var(--fg-2);border:1px solid var(--line-strong);border-radius:8px}.is-done .outline-num{color:var(--ok);border-color:var(--ok)}.outline-ico{font-size:1.3rem}.outline-text{display:flex;flex-direction:column;min-width:0}.outline-text strong{color:var(--fg-0);font-size:.98rem}.outline-text span{color:var(--fg-3);font-size:.84rem;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.outline-min{margin-left:auto;flex-shrink:0;font-family:var(--font-mono);font-size:.8rem;color:var(--fg-3)}.home-foot{text-align:center;color:var(--fg-3);font-size:.86rem;padding:40px 0 20px;border-top:1px solid var(--line);margin-top:40px}.home-foot-gh{display:inline-flex;align-items:center;gap:8px;padding:9px 18px;border:1px solid var(--line-strong);border-radius:99px;color:var(--fg-1);font-size:.9rem;font-weight:600;transition:all .18s}.home-foot-gh:hover{text-decoration:none;color:var(--fg-0);border-color:var(--rust-deep);background:var(--bg-2);transform:translateY(-1px)}.home-foot-meta{margin-top:16px;color:var(--fg-3)}@media (max-width: 760px){.why-cards{grid-template-columns:1fr}.hero-stats{gap:28px}}.chapter{max-width:var(--content-max);margin:0 auto}.chapter-meta{display:flex;justify-content:space-between;align-items:center;font-size:.8rem}.chapter-kicker{color:var(--rust);font-weight:700;letter-spacing:.04em}.chapter-mins{color:var(--fg-3)}.chapter-title{font-size:clamp(1.8rem,4vw,2.6rem);margin:.6rem 0 .4rem;display:flex;align-items:center;gap:14px}.chapter-title-icon{font-size:.9em}.chapter-subtitle{font-size:1.1rem;color:var(--fg-2);margin:0}.chapter-loading{padding:40px;text-align:center;color:var(--fg-3)}.chapter-done{margin:3rem 0 1rem;text-align:center}.done-btn{font-size:.95rem;font-weight:600;padding:12px 28px;border-radius:99px;border:1px solid var(--rust-deep);background:var(--rust-soft);color:var(--rust);cursor:pointer;transition:all .2s}.done-btn:hover{background:#dea58433}.done-btn.is-done{background:var(--ok-soft);border-color:var(--ok);color:var(--ok)}.chapter-nav{display:grid;grid-template-columns:1fr 1fr;gap:16px;margin-top:2rem}.chapter-nav a{display:flex;flex-direction:column;gap:4px;padding:16px 18px;border:1px solid var(--line);border-radius:var(--radius);background:var(--bg-1);transition:all .18s}.chapter-nav a:hover{border-color:var(--rust-deep);background:var(--bg-2);text-decoration:none;transform:translateY(-2px)}.nav-next{text-align:right}.nav-dir{font-size:.78rem;color:var(--fg-3)}.nav-name{color:var(--fg-0);font-weight:600}@media (max-width: 600px){.chapter-nav{grid-template-columns:1fr}}