:root{--primary:#4f46e5;--primary-dark:#4338ca;--violet:#7c3aed;--sky:#0ea5e9;--ink:#0f172a;--ink-soft:#334155;--muted:#64748b;--line:#e2e8f0;--bg:#ffffff;--bg-soft:#f8fafc;--grad:linear-gradient(120deg,#4f46e5 0%,#7c3aed 55%,#0ea5e9 110%);--radius:16px;--shadow:0 10px 40px -12px rgba(79,70,229,.18);--shadow-lg:0 24px 60px -16px rgba(79,70,229,.25);--font:"HarmonyOS Sans SC","PingFang SC","Microsoft YaHei","Source Han Sans SC",sans-serif;--mono:"JetBrains Mono","Cascadia Mono",Consolas,monospace}*{margin:0;padding:0;box-sizing:border-box}html{scroll-behavior:smooth}body{font-family:var(--font);color:var(--ink);background:var(--bg);line-height:1.75;-webkit-font-smoothing:antialiased}a{color:inherit;text-decoration:none}img{max-width:100%;display:block}.wrap{max-width:1180px;margin:0 auto;padding:0 24px}.wrap-sm{max-width:920px;margin:0 auto;padding:0 24px} .booknav{position:sticky;top:0;z-index:200;background:rgba(255,255,255,.92);backdrop-filter:blur(14px);border-bottom:1px solid var(--line)}.booknav-inner{display:flex;align-items:center;justify-content:space-between;height:64px}.booknav-logo{display:flex;align-items:center;gap:10px;font-weight:800;font-size:17px;letter-spacing:.4px}.logo-mark{width:32px;height:32px;border-radius:9px;background:var(--grad);color:#fff;display:grid;place-items:center;font-size:16px;font-weight:800}.booknav-links{display:flex;gap:26px;align-items:center;font-size:14.5px;color:var(--ink-soft)}.booknav-links a:hover{color:var(--primary)}.booknav-links a.is-active{color:var(--primary);font-weight:700}.nav-cta{padding:8px 18px;border-radius:10px;background:var(--grad);color:#fff !important;font-weight:600;box-shadow:var(--shadow);font-size:14px} .pill{display:inline-flex;align-items:center;gap:7px;padding:6px 15px;border-radius:999px;font-size:13.5px;font-weight:600;background:#eef2ff;color:var(--primary);border:1px solid #e0e7ff}.pill-int{background:#ecfdf5;color:#047857;border-color:#a7f3d0}.tag{display:inline-block;font-size:13px;font-weight:700;color:var(--primary);background:#eef2ff;border-radius:999px;padding:5px 15px;letter-spacing:1px}.sec-head{text-align:center;max-width:760px;margin:0 auto 52px}.sec-head h2{font-size:34px;font-weight:800;letter-spacing:-.5px;margin:14px 0 12px}.sec-head p{color:var(--muted);font-size:16.5px}section.bk{padding:88px 0}.bk-soft{background:var(--bg-soft)}.btn{display:inline-block;padding:13px 30px;border-radius:12px;font-size:15.5px;font-weight:600;transition:.2s;cursor:pointer;border:none}.btn-primary{background:var(--grad);color:#fff;box-shadow:var(--shadow)}.btn-primary:hover{transform:translateY(-2px);box-shadow:var(--shadow-lg)}.btn-ghost{background:#fff;color:var(--ink);border:1px solid var(--line)}.btn-ghost:hover{border-color:var(--primary);color:var(--primary)}.btn-sm{padding:9px 20px;font-size:14px} .bk-hero{position:relative;padding:104px 0 84px;overflow:hidden;border-bottom:1px solid var(--line)}.blob{position:absolute;border-radius:50%;filter:blur(90px);opacity:.34;pointer-events:none}.blob.b1{width:520px;height:520px;background:#c7d2fe;top:-170px;right:-130px}.blob.b2{width:420px;height:420px;background:#ddd6fe;bottom:-190px;left:-120px}.bk-hero-inner{position:relative;max-width:880px}.bk-hero h1{font-size:46px;line-height:1.25;font-weight:800;letter-spacing:-1.2px;margin:22px 0 18px}.bk-hero h1 .grad{background:var(--grad);-webkit-background-clip:text;background-clip:text;color:transparent}.bk-hero p.sub{font-size:18px;color:var(--muted);max-width:660px}.bk-hero-actions{display:flex;gap:14px;flex-wrap:wrap;margin-top:32px}.bk-stat{display:grid;grid-template-columns:repeat(4,1fr);gap:18px;margin-top:52px}.bk-stat .item{background:#fff;border:1px solid var(--line);border-radius:14px;padding:20px 22px}.bk-stat b{display:block;font-size:30px;font-weight:800;letter-spacing:-1px;background:var(--grad);-webkit-background-clip:text;background-clip:text;color:transparent;font-variant-numeric:tabular-nums}.bk-stat span{font-size:13.5px;color:var(--muted)} .ladder{display:grid;grid-template-columns:repeat(3,1fr);gap:22px}.ladder .card{position:relative;background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:30px 26px;overflow:hidden;transition:.25s;display:flex;flex-direction:column}.ladder .card::before{content:"";position:absolute;top:0;left:0;right:0;height:4px}.ladder .card.pa::before{background:linear-gradient(90deg,#3b82f6,#60a5fa)}.ladder .card.pb::before{background:linear-gradient(90deg,#f97316,#fb923c)}.ladder .card.pc::before{background:linear-gradient(90deg,#dc2626,#f87171)}.ladder .card:hover{transform:translateY(-4px);box-shadow:var(--shadow);border-color:#c7d2fe}.ladder .lv{font-size:12.5px;font-weight:800;letter-spacing:1px;color:var(--primary);background:#eef2ff;border-radius:7px;padding:4px 10px;align-self:flex-start}.ladder .card.pb .lv{color:#c2410c;background:#fff7ed}.ladder .card.pc .lv{color:#b91c1c;background:#fef2f2}.ladder h3{font-size:21px;font-weight:800;margin:14px 0 6px}.ladder p.goal{color:var(--muted);font-size:14.5px;min-height:44px}.ladder ul{list-style:none;margin:16px 0 20px;display:grid;gap:7px}.ladder ul li{font-size:13.8px;color:var(--ink-soft);padding-left:20px;position:relative;line-height:1.62}.ladder ul li::before{content:"▸";position:absolute;left:2px;color:var(--primary)}.ladder .foot{margin-top:auto;border-top:1px dashed var(--line);padding-top:14px;display:flex;gap:8px;flex-wrap:wrap;align-items:center;font-size:12.5px;color:var(--muted)}.ladder .foot .chip{background:var(--bg-soft);border:1px solid var(--line);border-radius:7px;padding:3px 9px} .ch-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(258px,1fr));gap:18px}.ch-card{background:#fff;border:1px solid var(--line);border-radius:14px;padding:22px 22px 20px;transition:.22s;display:flex;flex-direction:column;gap:9px}.ch-card:hover{transform:translateY(-3px);box-shadow:var(--shadow);border-color:#c7d2fe}.ch-card .no{font-size:12px;font-weight:800;color:var(--primary);background:#eef2ff;border-radius:7px;padding:3px 9px;align-self:flex-start;letter-spacing:.5px}.ch-card h4{font-size:16.5px;font-weight:750;line-height:1.45}.ch-card p{font-size:13.2px;color:var(--muted);line-height:1.66;min-height:44px}.ch-card .meta{font-size:12px;color:#94a3b8;display:flex;gap:10px;flex-wrap:wrap;margin-top:auto;padding-top:10px;border-top:1px solid #f1f5f9} .plan-note{background:#fffbeb;border:1px solid #fde68a;border-radius:13px;padding:16px 20px;color:#92400e;font-size:14px;line-height:1.7;margin-bottom:34px}.plan-note b{color:#78350f}.plan-block{background:#fff;border:1px solid var(--line);border-radius:16px;padding:8px 30px 26px;margin-bottom:26px;box-shadow:0 1px 0 rgba(15,23,42,.03)}.plan-block h3{font-size:19px;font-weight:800;margin:22px 0 10px}.plan-block ul,.plan-block ol{margin:8px 0 8px 20px;display:grid;gap:7px}.plan-block li{font-size:14.6px;color:var(--ink-soft)}.plan-block blockquote{margin:16px 0;padding:12px 18px;border-left:3px solid var(--primary);background:var(--bg-soft);border-radius:0 10px 10px 0;color:var(--ink-soft);font-size:14.3px}.plan-block h2{font-size:25px;font-weight:800;margin:26px 0 10px;padding-bottom:10px;border-bottom:1px solid var(--line)}.plan-block p{margin:10px 0;font-size:14.8px;color:var(--ink-soft)}.plan-block table{width:100%;border-collapse:collapse;margin:16px 0;font-size:13.8px;background:#fff}.plan-block th{background:var(--bg-soft);text-align:left;padding:11px 13px;border-bottom:1px solid var(--line);color:var(--ink-soft);font-size:13px;white-space:nowrap}.plan-block td{padding:11px 13px;border-bottom:1px solid #f1f5f9;vertical-align:top;color:var(--ink-soft)}.plan-block strong{color:var(--ink)}.plan-block code{background:#f1f5f9;border-radius:5px;padding:1px 6px;font-family:var(--mono);font-size:13px}.plan-block hr{border:none;border-top:1px dashed var(--line);margin:22px 0} .cat-table{width:100%;border-collapse:collapse;font-size:14px;background:#fff;border:1px solid var(--line);border-radius:14px;overflow:hidden}.cat-table th{background:var(--bg-soft);text-align:left;padding:13px 16px;font-size:13px;color:var(--ink-soft);border-bottom:1px solid var(--line);white-space:nowrap}.cat-table td{padding:13px 16px;border-bottom:1px solid #f1f5f9;vertical-align:top;color:var(--ink-soft)}.cat-table tr:last-child td{border-bottom:none}.cat-table tr:hover td{background:#fcfdff}.cat-table a.t{font-weight:700;color:var(--ink)}.cat-table a.t:hover{color:var(--primary)}.cat-table .secs{font-size:12.8px;color:var(--muted);line-height:1.7} .rd-toolbar{position:sticky;top:64px;z-index:150;background:rgba(255,255,255,.95);backdrop-filter:blur(12px);border-bottom:1px solid var(--line)}.rd-toolbar-inner{display:flex;align-items:center;gap:14px;height:56px;flex-wrap:nowrap;overflow-x:auto}.rd-select{border:1px solid var(--line);border-radius:10px;padding:7px 12px;font-size:14px;font-family:var(--font);color:var(--ink);background:#fff;max-width:280px}.rd-chip{border:1px solid var(--line);background:#fff;border-radius:999px;padding:5px 14px;font-size:13px;color:var(--ink-soft);cursor:pointer;white-space:nowrap;transition:.15s}.rd-chip:hover{border-color:#c7d2fe;color:var(--primary)}.rd-chip.is-on{background:#eef2ff;border-color:#c7d2fe;color:var(--primary);font-weight:700}.rd-spacer{flex:1}.rd-prog-label{font-size:13px;color:#64748b;white-space:nowrap}.rd-prog{height:3px;background:#f1f5f9}.rd-prog i{display:block;height:100%;width:0;background:var(--grad);transition:width .12s}.rd-body{display:grid;grid-template-columns:278px minmax(0,1fr);gap:40px;max-width:1180px;margin:0 auto;padding:34px 24px 90px;align-items:start}.rd-side{position:sticky;top:132px;max-height:calc(100vh - 160px);overflow-y:auto;font-size:13.6px;padding-right:6px}.rd-side::-webkit-scrollbar{width:6px}.rd-side::-webkit-scrollbar-thumb{background:#e2e8f0;border-radius:3px}.rd-side h5{font-size:12px;letter-spacing:1px;color:#94a3b8;font-weight:800;margin:16px 0 8px}.rd-side a{display:block;padding:5px 9px;border-radius:8px;color:var(--ink-soft);line-height:1.55;border-left:2px solid transparent}.rd-side a:hover{background:var(--bg-soft);color:var(--primary)}.rd-side a.h2{font-weight:650;margin-top:6px}.rd-side a.h3{padding-left:20px;font-size:12.8px;color:var(--muted);display:none}.rd-side .grp.open a.h3{display:block}.rd-side a.h3.is-active{color:var(--primary)}.rd-side a.is-active{background:#eef2ff;color:var(--primary);border-left-color:var(--primary);font-weight:700}.rd-main{min-width:0}.rd-crumb{font-size:13px;color:var(--muted);display:flex;gap:8px;align-items:center;flex-wrap:wrap;margin-bottom:6px}.rd-crumb .lvb{font-size:11.5px;font-weight:700;border-radius:999px;padding:2px 9px}.rd-main h1.rd-title{font-size:33px;font-weight:800;letter-spacing:-.6px;line-height:1.35;margin:6px 0 18px;padding-bottom:18px;border-bottom:2px solid var(--line)}p.rd-note{margin:-8px 0 22px;font-size:12.8px;color:#7c8798;background:var(--bg-soft);border:1px dashed var(--line);border-radius:9px;padding:9px 13px;line-height:1.62}.rd-navbottom{display:flex;justify-content:space-between;gap:14px;margin-top:56px;padding-top:26px;border-top:1px solid var(--line)}.rd-navbottom a{flex:1;border:1px solid var(--line);border-radius:12px;padding:16px 20px;font-size:14.5px;color:var(--ink-soft);transition:.2s}.rd-navbottom a:hover{border-color:#c7d2fe;box-shadow:var(--shadow)}.rd-navbottom a b{display:block;font-size:12.5px;color:#94a3b8;font-weight:700;margin-bottom:4px}.rd-navbottom a.next{text-align:right}.rd-loading{color:var(--muted);padding:60px 0;text-align:center;font-size:15px} .md{font-size:15.7px;color:#1e293b;line-height:1.92;word-break:break-word}.md h2{font-size:23.5px;font-weight:800;letter-spacing:-.3px;margin:46px 0 16px;padding:0 0 10px 14px;border-left:4px solid var(--primary);border-bottom:1px solid var(--line);scroll-margin-top:150px}.md h3{font-size:18.5px;font-weight:750;margin:34px 0 12px;color:var(--ink);scroll-margin-top:150px}.md h4{font-size:16.5px;font-weight:700;margin:26px 0 10px;color:var(--ink-soft)}.md p{margin:14px 0}.md strong{color:var(--ink);font-weight:750}.md ul,.md ol{margin:14px 0 14px 24px;display:grid;gap:7px}.md li{padding-left:2px}.md li>p{margin:4px 0}.md blockquote{margin:20px 0;padding:15px 20px;background:var(--bg-soft);border-left:4px solid #a5b4fc;border-radius:0 12px 12px 0;color:var(--ink-soft);font-size:15.2px}.md blockquote p{margin:6px 0}.md blockquote strong{color:var(--primary-dark)}.md table{width:100%;border-collapse:collapse;margin:20px 0;font-size:14.2px;background:#fff;border:1px solid var(--line);border-radius:12px;overflow:hidden;display:table}.md th{background:linear-gradient(180deg,#f8fafc,#f1f5f9);text-align:left;padding:11px 14px;font-size:13.4px;color:var(--ink);font-weight:700;border-bottom:1px solid var(--line)}.md td{padding:11px 14px;border-bottom:1px solid #f1f5f9;vertical-align:top;color:var(--ink-soft)}.md tbody tr:last-child td{border-bottom:none}.md tbody tr:hover td{background:#fcfdff}.md code{background:#f1f5f9;border-radius:6px;padding:2px 7px;font-family:var(--mono);font-size:13.4px;color:#be185d}.md pre{background:#0f172a;color:#e2e8f0;border-radius:12px;padding:18px 20px;overflow-x:auto;margin:20px 0}.md pre code{background:none;color:inherit;padding:0;font-size:13.4px}.md hr{border:none;border-top:1px dashed var(--line);margin:34px 0}.md .lvl{display:inline-block;font-size:12px;font-weight:700;border-radius:999px;padding:1px 8px;vertical-align:middle;margin-left:6px;background:#f1f5f9;color:#475569}.md .rd-h2-chip{display:inline-block;font-size:12px;font-weight:700;border-radius:999px;padding:2px 9px;margin-left:9px;vertical-align:middle}.md a{color:var(--primary);border-bottom:1px solid #c7d2fe}.md em{font-style:normal;background:#fef9c3;padding:0 2px;border-radius:3px}.md mark{background:#fef08a;padding:0 3px;border-radius:3px} @media(max-width:1200px){.rd-prog-label{display:none}}@media(max-width:980px){.bk-stat{grid-template-columns:repeat(2,1fr)}.ladder{grid-template-columns:1fr}.rd-body{grid-template-columns:1fr;padding-top:22px;gap:20px}.rd-side{position:static;max-height:none;border:1px solid var(--line);border-radius:12px;padding:12px;background:#fff}.rd-side a.h3{display:block}.bk-hero h1{font-size:34px}.booknav-links{gap:16px;font-size:13.5px}.booknav-links a:not(.nav-cta){display:none}}