/* How to Live Better — v8 "Blueprint"
   Patterns: see /STUDY_NOTES.md. Blueprint rails (Magic UI), tight display type (Magic UI/Vercel), two-tone lede + split pill (Cult UI),
   CTA pair w/ under-glow (Aceternity/Magic UI), product window hero (Linear/React Bits), tray+tiles (Cult UI), hairline cell grid (Vercel),
   wordmark strip (Aceternity), search + ↳ suggestions (Refero), docs shell w/ numbered inline titles + hatch gutters (Beautiful UI). */
@font-face{font-family:Geist;src:url(fonts/geist.woff2) format('woff2');font-weight:100 900;font-display:swap}
@font-face{font-family:'Geist Mono';src:url(fonts/geist-mono.woff2) format('woff2');font-weight:100 900;font-display:swap}

:root{
  --bg:#fafafa;--surface:#fff;--tray:#f4f4f5;--sunk:#f6f6f7;--dot:#dedee3;
  --line:#e7e7ea;--line-2:#d9d9de;--hatch:rgba(9,9,11,.035);
  --fg:#09090b;--fg-2:#52525b;--fg-3:#8b8b94;--fg-4:#b4b4bc;
  --inv:#09090b;--inv-fg:#fafafa;
  --a:#16a34a;--b:#2563eb;--c:#a1a1aa;--warn:#c2410c;
  --a-bg:rgba(22,163,74,.09);--b-bg:rgba(37,99,235,.08);
  --ring:0 0 0 1px var(--line);
  --sh-1:0 1px 2px rgba(9,9,11,.04),0 1px 1px rgba(9,9,11,.03);
  --sh-2:0 1px 1px rgba(9,9,11,.03),0 4px 8px -2px rgba(9,9,11,.05),0 16px 32px -12px rgba(9,9,11,.10);
  --sh-win:0 0 0 1px rgba(9,9,11,.06),0 2px 4px rgba(9,9,11,.04),0 24px 48px -16px rgba(9,9,11,.16),0 48px 96px -32px rgba(9,9,11,.12);
  --sans:Geist,"PingFang SC","Hiragino Sans GB","Noto Sans SC","Microsoft YaHei",system-ui,sans-serif;
  --mono:"Geist Mono",ui-monospace,SFMono-Regular,Menlo,monospace;
  --ease:cubic-bezier(.22,1,.36,1);
  --max:1200px;--gut:32px;--hh:60px;
  color-scheme:light;
}
[data-theme=dark]{
  --bg:#08090a;--surface:#0f1011;--tray:#121314;--sunk:#141516;--dot:rgba(255,255,255,.07);
  --line:rgba(255,255,255,.08);--line-2:rgba(255,255,255,.13);--hatch:rgba(255,255,255,.025);
  --fg:#f7f8f8;--fg-2:#a1a1aa;--fg-3:#71717a;--fg-4:#4b4b52;
  --inv:#f7f8f8;--inv-fg:#08090a;
  --a:#4ade80;--b:#60a5fa;--c:#71717a;--warn:#fb923c;
  --a-bg:rgba(74,222,128,.09);--b-bg:rgba(96,165,250,.09);
  --sh-1:none;--sh-2:0 0 0 1px rgba(255,255,255,.02),0 16px 32px -12px rgba(0,0,0,.6);
  --sh-win:0 0 0 1px rgba(255,255,255,.09),0 24px 64px -16px rgba(0,0,0,.8),inset 0 1px 0 rgba(255,255,255,.05);
  color-scheme:dark;
}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-padding-top:calc(var(--hh) + 20px)}
body{margin:0;background:var(--bg);color:var(--fg);font:15px/1.65 var(--sans);-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility;line-break:strict;overflow-x:hidden}
a{color:inherit;text-decoration:none}
button{font:inherit;color:inherit;background:none;border:0;padding:0;cursor:pointer}
input,select{font:inherit;color:inherit}
svg{width:16px;height:16px;fill:none;stroke:currentColor;stroke-width:1.6;stroke-linecap:round;stroke-linejoin:round;flex:none}
::selection{background:color-mix(in srgb,var(--b) 22%,transparent)}
:focus-visible{outline:2px solid var(--b);outline-offset:2px;border-radius:6px}
mark{background:color-mix(in srgb,#facc15 40%,transparent);color:inherit;border-radius:3px;padding:0 1px}
code,kbd{font-family:var(--mono);font-size:.86em}
.wrap{width:100%;max-width:var(--max);margin:0 auto;padding:0 var(--gut);position:relative}

/* 1 · Blueprint rails (Magic UI / shadcnblocks) */
.rails{position:fixed;inset:0;pointer-events:none;z-index:0}
.rails::before,.rails::after{content:"";position:absolute;top:0;bottom:0;width:1px;background:var(--line);left:max(0px,calc(50% - var(--max)/2))}
.rails::after{left:auto;right:max(0px,calc(50% - var(--max)/2))}
main,footer{position:relative;z-index:1}
.sec,.strip,.hero{position:relative}
.sec::before,.strip::before{content:"";position:absolute;left:0;right:0;top:0;height:1px;background:var(--line)}
.sec>.wrap::before,.sec>.wrap::after{content:"+";position:absolute;top:-12px;font:300 16px/1 var(--mono);color:var(--fg-4);left:-5px}
.sec>.wrap::after{left:auto;right:-5px}
@media (max-width:1264px){.rails,.sec>.wrap::before,.sec>.wrap::after{display:none}}

/* chrome */
.top{position:sticky;top:0;z-index:40;height:var(--hh);background:color-mix(in srgb,var(--bg) 82%,transparent);backdrop-filter:saturate(1.6) blur(14px);-webkit-backdrop-filter:saturate(1.6) blur(14px);border-bottom:1px solid transparent;transition:border-color .2s}
.top.scrolled{border-bottom-color:var(--line)}
.bar{display:flex;align-items:center;gap:6px;height:100%}
.logo{display:flex;align-items:center;gap:10px;font-weight:600;font-size:15px;letter-spacing:-.01em;margin-right:18px;white-space:nowrap}
.mark{width:26px;height:26px;border-radius:8px;background:var(--inv);color:var(--inv-fg);display:grid;place-items:center;box-shadow:inset 0 1px 0 rgba(255,255,255,.2)}
.mark svg{width:15px;height:15px;stroke-width:2.6}
.mark.sm{width:20px;height:20px;border-radius:6px}.mark.sm svg{width:12px;height:12px}
.tabs{display:flex;gap:2px}
.tabs a{font-size:14px;color:var(--fg-2);padding:6px 11px;border-radius:999px;transition:color .15s,background .15s;white-space:nowrap}
.tabs a:hover{color:var(--fg)}
.tabs a.on{color:var(--fg);background:var(--tray);box-shadow:inset 0 0 0 1px var(--line)}
.sbtn{margin-left:auto;display:flex;align-items:center;gap:8px;height:34px;width:220px;padding:0 6px 0 11px;border-radius:10px;background:var(--surface);box-shadow:inset 0 0 0 1px var(--line),var(--sh-1);color:var(--fg-3);font-size:13.5px;transition:box-shadow .15s}
.sbtn:hover{box-shadow:inset 0 0 0 1px var(--line-2),var(--sh-1)}
.sbtn span{flex:1;text-align:left}
kbd{display:inline-grid;place-items:center;min-width:20px;height:20px;padding:0 5px;border-radius:5px;background:var(--tray);box-shadow:inset 0 0 0 1px var(--line);color:var(--fg-3);font-size:11px}
.icon{width:34px;height:34px;display:grid;place-items:center;border-radius:10px;color:var(--fg-2);transition:background .15s,color .15s}
.icon:hover{background:var(--tray);color:var(--fg)}
[data-theme=dark] .sun,[data-theme=light] .moon{display:none}

/* motion — one orchestrated load (anthropic frontend-design), transform/opacity only */
.ld{animation:ld .8s var(--ease) both;animation-delay:calc(var(--i,0)*70ms + 40ms)}
@keyframes ld{from{opacity:0;transform:translateY(12px);filter:blur(6px)}to{opacity:1;transform:none;filter:none}}
@media (prefers-reduced-motion:reduce){*,*::before,*::after{animation:none!important;transition:none!important}}

/* buttons (Aceternity pair + Magic UI under-glow) */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;height:44px;padding:0 20px;border-radius:999px;font-size:14.5px;font-weight:500;white-space:nowrap;transition:transform .2s var(--ease),box-shadow .2s,background .2s;position:relative}
.btn:active{transform:scale(.98)}
.btn.pri{background:var(--inv);color:var(--inv-fg);padding:0 6px 0 20px;box-shadow:inset 0 1px 0 rgba(255,255,255,.18),0 1px 2px rgba(0,0,0,.2)}
.btn.pri::after{content:"";position:absolute;left:14%;right:14%;bottom:-12px;height:22px;z-index:-1;border-radius:50%;background:linear-gradient(90deg,#22c55e,#3b82f6,#a855f7);filter:blur(16px);opacity:.38;transition:opacity .25s}
.btn.pri:hover::after{opacity:.6}
.btn .bi{width:32px;height:32px;border-radius:50%;background:rgba(255,255,255,.14);display:grid;place-items:center;transition:transform .25s var(--ease)}
[data-theme=dark] .btn .bi{background:rgba(0,0,0,.08)}
.btn.pri:hover .bi{transform:translateX(2px)}
.btn.out{background:var(--surface);box-shadow:inset 0 0 0 1px var(--line-2),var(--sh-1)}
.btn.out:hover{box-shadow:inset 0 0 0 1px var(--fg-4),var(--sh-1)}
.btn.sm{height:34px;padding:0 14px;font-size:13.5px}
.btn.sm svg{width:14px;height:14px}
.btn.ghost{height:36px;padding:0 14px;font-size:13.5px;background:var(--surface);box-shadow:inset 0 0 0 1px var(--line)}

/* hero */
.hero{padding:72px 0 88px;overflow:hidden}
.hero::after{content:"";position:absolute;inset:0;z-index:-1;background-image:radial-gradient(var(--dot) 1px,transparent 1px);background-size:20px 20px;-webkit-mask:radial-gradient(60% 70% at 78% 40%,#000 0,transparent 70%);mask:radial-gradient(60% 70% at 78% 40%,#000 0,transparent 70%)}
.hgrid{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1.05fr);gap:56px;align-items:start}
.hcopy{padding-top:6px}
.lede{margin-top:0!important}
.announce{display:inline-flex;align-items:center;gap:10px;height:30px;padding:0 10px 0 4px;border-radius:999px;background:var(--surface);box-shadow:inset 0 0 0 1px var(--line),var(--sh-1);font-size:13px;color:var(--fg-3);transition:box-shadow .15s}
.announce:hover{box-shadow:inset 0 0 0 1px var(--line-2),var(--sh-1)}
.announce b{font-weight:500;color:var(--fg);background:var(--tray);box-shadow:inset 0 0 0 1px var(--line);padding:2px 9px;border-radius:999px}
.announce svg{width:13px;height:13px}
.hero h1{margin:22px 0 0;font-size:clamp(32px,4.6vw,58px);line-height:1.12;font-weight:600;letter-spacing:-.035em}
.hero h1 span{display:block}
.hero h1 span+span{color:var(--fg-3)}
.hero .hgrid{margin-top:36px}
.lede{margin:20px 0 0;font-size:17px;line-height:1.7;color:var(--fg-3);max-width:34em;text-wrap:pretty}
.lede b{color:var(--fg);font-weight:500}
.cta{display:flex;flex-wrap:wrap;gap:12px;margin-top:30px}
.hsearch{display:flex;align-items:center;gap:10px;height:52px;margin-top:28px;padding:0 10px 0 16px;border-radius:14px;background:var(--surface);box-shadow:inset 0 0 0 1px var(--line),var(--sh-2);max-width:520px;transition:box-shadow .2s}
.hsearch:focus-within{box-shadow:inset 0 0 0 1px var(--fg-4),0 0 0 4px color-mix(in srgb,var(--b) 12%,transparent),var(--sh-2)}
.hsearch svg{color:var(--fg-3)}
.hsearch input{flex:1;min-width:0;height:100%;border:0;outline:0;background:none;font-size:15px}
.hsearch input::placeholder{color:var(--fg-3)}
.hsearch input::-webkit-search-cancel-button{display:none}
.sugg{list-style:none;margin:14px 0 0;padding:0;display:grid;grid-template-columns:minmax(0,1fr);gap:2px;max-width:520px}
.sugg li{min-width:0}
.sugg a{display:flex;gap:10px;font-size:13.5px;color:var(--fg-2);padding:5px 6px;border-radius:8px;transition:background .15s,color .15s;min-width:0}
.sugg em{font-style:normal;overflow:hidden;white-space:nowrap;text-overflow:ellipsis;min-width:0}
.sugg a span{color:var(--fg-4);flex:none}
.sugg a:hover{background:var(--tray);color:var(--fg)}

/* 6 · Product window (Linear / React Bits) */
.hwin{position:relative;padding:22px 0 0 22px}
.sheet{position:absolute;border-radius:18px;background:var(--surface);box-shadow:var(--sh-2),inset 0 0 0 1px var(--line)}
.sheet.s1{inset:10px 10px 30px 12px;transform:rotate(-1.6deg);opacity:.85}
.sheet.s2{inset:0 20px 44px 0;transform:rotate(-3.4deg);opacity:.5}
.win{position:relative;border-radius:16px;background:var(--surface);box-shadow:var(--sh-win);overflow:hidden;display:flex;flex-direction:column;height:500px}
.wbar{display:flex;align-items:center;gap:14px;height:42px;padding:0 14px;border-bottom:1px solid var(--line);background:var(--sunk)}
.dots{display:flex;gap:6px}.dots i{width:10px;height:10px;border-radius:50%;background:var(--line-2)}
.path{font:12px var(--mono);color:var(--fg-3);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.wtabs{display:flex;gap:4px;padding:10px 12px 0;border-bottom:1px solid var(--line)}
.wtabs button{display:flex;align-items:center;gap:7px;font-size:13px;color:var(--fg-3);padding:7px 10px 9px;border-bottom:2px solid transparent;margin-bottom:-1px;transition:color .15s,border-color .2s}
.wtabs button span{font:11.5px var(--mono);color:var(--fg-4)}
.wtabs button:hover{color:var(--fg)}
.wtabs button.on{color:var(--fg);border-bottom-color:var(--fg)}
.wbody{flex:1;overflow:hidden;padding:20px 22px 0;position:relative;-webkit-mask:linear-gradient(#000 78%,transparent);mask:linear-gradient(#000 78%,transparent)}
.wbody .entry{animation:fadein .35s var(--ease)}
@keyframes fadein{from{opacity:0;transform:translateY(4px)}to{opacity:1;transform:none}}
.wopen{position:absolute;right:14px;bottom:14px;display:inline-flex;align-items:center;gap:6px;height:32px;padding:0 12px;border-radius:999px;background:var(--surface);box-shadow:inset 0 0 0 1px var(--line-2),var(--sh-2);font-size:13px;font-weight:500}
.wopen svg{width:14px;height:14px;transition:transform .2s var(--ease)}
.wopen:hover svg{transform:translateX(2px)}

/* 9 · wordmark strip (Aceternity) */
.strip{padding:30px 0 34px}
.strip p{margin:0 0 16px;text-align:center;font-size:13px;color:var(--fg-3)}
.marks{display:flex;flex-wrap:wrap;justify-content:center;gap:8px 34px}
.marks a{display:inline-flex;align-items:baseline;gap:6px;color:var(--fg-3);transition:color .15s}
.marks b{font-size:17px;font-weight:600;letter-spacing:-.02em}
.marks small{font:11px var(--mono);color:var(--fg-4)}
.marks a:hover{color:var(--fg)}

/* sections + headers (Cult UI) */
.sec{padding:76px 0 84px}
.sh{margin-bottom:32px;max-width:640px}
.sh.row{display:flex;align-items:flex-end;justify-content:space-between;gap:24px;max-width:none}
.sh.row>div{max-width:640px}
.kk{margin:0 0 10px;font-size:13px;color:var(--fg-3);font-weight:500}
.sh h2{margin:0;font-size:clamp(26px,3vw,36px);line-height:1.18;font-weight:600;letter-spacing:-.03em}
.sh .sub{margin:12px 0 0;color:var(--fg-3);font-size:15.5px;line-height:1.7}
.sh .sub b{color:var(--fg);font-weight:500}
.sh.sm h2{font-size:22px}
.lg{display:inline-block;width:8px;height:8px;border-radius:2px;margin:0 4px 0 8px;vertical-align:0}
.lg.a{background:var(--a)}.lg.b{background:var(--b)}.lg.c{background:var(--c)}

/* 7 · tray + tiles (Cult UI, double bezel) */
.tray{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:8px;padding:8px;border-radius:22px;background-color:var(--tray);background-image:radial-gradient(var(--dot) 1px,transparent 1px);background-size:8px 8px;box-shadow:inset 0 0 0 1px var(--line)}
.tile{display:flex;flex-direction:column;border-radius:15px;background:var(--surface);box-shadow:0 0 0 1px var(--line),var(--sh-1);overflow:hidden}
.stage{padding:18px 18px 14px;flex:1}
.th{display:flex;align-items:center;gap:9px}
.ti{width:28px;height:28px;border-radius:8px;display:grid;place-items:center;background:var(--tray);box-shadow:inset 0 0 0 1px var(--line);color:var(--fg-2)}
.ti svg{width:15px;height:15px}
.th b{font-size:16px;font-weight:600;letter-spacing:-.01em}
.tn{margin-left:auto;font:500 13px var(--mono);color:var(--fg-3)}
.tv{margin:12px 0 14px;font-size:13.5px;line-height:1.6;color:var(--fg-2);min-height:4.8em;text-wrap:pretty}
.tl{list-style:none;margin:0;padding:12px 0 0;border-top:1px dashed var(--line-2);display:grid;gap:2px}
.tl a{display:flex;gap:7px;font-size:13px;line-height:1.5;color:var(--fg-2);padding:4px 0;transition:color .15s}
.tl a span{color:var(--fg-4);flex:none}
.tl a:hover{color:var(--fg)}
.tf{display:flex;align-items:center;justify-content:space-between;height:42px;padding:0 16px;border-top:1px solid var(--line);font-size:12.5px;color:var(--fg-3);transition:background .15s,color .15s}
.tf .go{display:inline-flex;align-items:center;gap:5px;color:var(--fg-2)}
.tf svg{width:13px;height:13px;transition:transform .2s var(--ease)}
.tf:hover{background:var(--sunk);color:var(--fg)}.tf:hover svg{transform:translateX(2px)}

/* 8 · hairline cell grid (Vercel) */
.cgrid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:1px;background:var(--line);border-radius:16px;overflow:hidden;box-shadow:0 0 0 1px var(--line)}
.cell{display:grid;grid-template-columns:34px 1fr;grid-template-rows:auto 1fr auto;column-gap:8px;padding:20px 22px 18px;background:var(--surface);min-height:148px;transition:background .15s}
.cell:hover{background:var(--sunk)}
.cn{grid-row:1/4;font:500 13px/24px var(--mono);color:var(--fg-4)}
.cell b{font-size:16px;font-weight:600;line-height:24px;letter-spacing:-.01em}
.cell small{margin-top:4px;font-size:13px;line-height:1.6;color:var(--fg-3);display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.cf{display:flex;align-items:center;gap:10px;margin-top:14px}
.cc{font:11.5px var(--mono);color:var(--fg-3);white-space:nowrap}
.ca{margin-left:auto;color:var(--fg-4);transition:transform .2s var(--ease),color .15s}
.ca svg{width:14px;height:14px}
.cell:hover .ca{color:var(--fg);transform:translateX(2px)}
.ev{display:flex;width:64px;height:4px;border-radius:2px;overflow:hidden;background:var(--line);flex:none}
.ev i{display:block;height:100%}.ev .a{background:var(--a)}.ev .b{background:var(--b)}.ev .c{background:var(--c)}

/* lists */
.two{display:grid;grid-template-columns:1fr 1fr;gap:56px}
.dlist{display:flex;flex-direction:column;border-top:1px solid var(--line)}
.drow{display:grid;grid-template-columns:1fr auto;gap:4px 18px;padding:15px 2px;border-bottom:1px solid var(--line);transition:background .15s}
.drow b{font-size:14.5px;font-weight:600;letter-spacing:-.005em}
.drow small{grid-column:1;font-size:13px;line-height:1.6;color:var(--fg-3);display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.drow .dm{grid-column:2;grid-row:1/3;align-self:center;font:11.5px var(--mono);color:var(--fg-3);white-space:nowrap}
.drow:hover b{text-decoration:underline;text-decoration-color:var(--fg-4);text-underline-offset:3px}
.more{display:inline-flex;align-items:center;gap:6px;margin-top:16px;font-size:13.5px;font-weight:500;color:var(--fg-2)}
.more svg{width:14px;height:14px}.more:hover{color:var(--fg)}
.notes{margin-top:28px;border-radius:14px;background:var(--tray);box-shadow:inset 0 0 0 1px var(--line);padding:6px 16px}
.nt{display:grid;grid-template-columns:52px 1fr;gap:12px;padding:12px 0;border-bottom:1px dashed var(--line-2)}
.nt:last-child{border-bottom:0}
.nk{font-size:12.5px;font-weight:600;color:var(--fg-2);line-height:1.7}
.nt p{margin:0;font-size:13px;line-height:1.7;color:var(--fg-2)}
.nt a,.prose a,.intro a,.note a,.cg a,.human a{color:var(--fg);text-decoration:underline;text-decoration-color:var(--fg-4);text-underline-offset:3px}

/* 11 · chapter page — docs shell (Beautiful UI) */
.cpage{display:grid;grid-template-columns:240px minmax(0,1fr);gap:56px;padding-top:36px;padding-bottom:80px}
.side{position:sticky;top:calc(var(--hh) + 20px);align-self:start;max-height:calc(100vh - var(--hh) - 40px);display:flex;flex-direction:column;gap:22px}
.group.grow{min-height:0;display:flex;flex-direction:column}
.gt{display:flex;justify-content:space-between;font-size:12.5px;font-weight:500;color:var(--fg-3);margin-bottom:8px;padding:0 8px}
.gt small{font:11px var(--mono);color:var(--fg-4)}
.snav{overflow:auto;scrollbar-width:thin;display:flex;flex-direction:column;gap:1px;padding-right:4px;margin-right:-4px}
.snav a{display:grid;grid-template-columns:24px 1fr auto;align-items:baseline;gap:6px;padding:6px 8px;border-radius:8px;font-size:13.5px;line-height:1.45;color:var(--fg-2);transition:background .12s,color .12s}
.snav a:hover{background:var(--tray);color:var(--fg)}
.snav a.on{background:var(--surface);color:var(--fg);font-weight:500;box-shadow:0 0 0 1px var(--line),var(--sh-1)}
.sn,.sc{font:11.5px var(--mono);color:var(--fg-4)}
.seg{display:inline-flex;gap:2px;padding:3px;border-radius:11px;background:var(--tray);box-shadow:inset 0 0 0 1px var(--line)}
.seg.col{display:flex;flex-direction:column;width:100%}
.chip{display:inline-flex;align-items:center;gap:7px;height:30px;padding:0 10px;border-radius:8px;font-size:13px;color:var(--fg-2);white-space:nowrap;transition:background .15s,color .15s,box-shadow .15s}
.chip:hover{color:var(--fg)}
.chip .n{font:11px var(--mono);color:var(--fg-4);margin-left:auto}
.chip .ic{display:grid;color:var(--fg-3)}.chip .ic svg{width:14px;height:14px}
.chip.on,.chip[aria-pressed=true]{background:var(--surface);color:var(--fg);box-shadow:0 0 0 1px var(--line-2),var(--sh-1)}
.chip.on .n{color:var(--fg-3)}
.mchap{display:none}
.crumbs{display:flex;gap:8px;margin:0 0 18px;font-size:13px;color:var(--fg-3)}
.crumbs a:hover{color:var(--fg)}.crumbs span:not(:last-child){color:var(--fg-4)}
.chead h1{margin:0;font-size:clamp(30px,3.6vw,44px);line-height:1.15;font-weight:600;letter-spacing:-.03em;display:flex;align-items:baseline;gap:16px}
.chead .no{font:400 .5em var(--mono);color:var(--fg-4);letter-spacing:0}
.chead .q{margin:14px 0 0;font-size:16.5px;line-height:1.7;color:var(--fg-3);max-width:40em;text-wrap:pretty}
.chead .q b{color:var(--fg);font-weight:500}
.cstat{display:flex;flex-wrap:wrap;align-items:center;gap:8px 22px;margin-top:20px;font-size:13px;color:var(--fg-3)}
.cstat b{font:500 13px var(--mono);color:var(--fg)}
.cstat .ev{width:96px}
.intro{margin-top:26px;border-radius:14px;background:var(--tray);box-shadow:inset 0 0 0 1px var(--line)}
.intro summary{display:flex;align-items:center;justify-content:space-between;cursor:pointer;list-style:none;padding:12px 16px;font-size:13.5px;font-weight:500;color:var(--fg-2)}
.intro summary::-webkit-details-marker{display:none}
.intro .chev{transition:transform .2s var(--ease)}.intro[open] .chev{transform:rotate(180deg)}
.intro .body{margin:0 6px 6px;padding:4px 18px 8px;border-radius:10px;background:var(--surface);box-shadow:0 0 0 1px var(--line);font-size:14px;line-height:1.8;color:var(--fg-2)}
.intro .body strong{color:var(--fg)}
.fbar{position:sticky;top:var(--hh);z-index:20;display:flex;flex-wrap:wrap;align-items:center;gap:10px;margin:22px calc(var(--gut)*-1 + 20px) 0;padding:12px calc(var(--gut) - 20px);background:color-mix(in srgb,var(--bg) 88%,transparent);backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px);border-bottom:1px solid var(--line)}
.mini{display:flex;align-items:center;gap:8px;height:36px;padding:0 12px;border-radius:10px;background:var(--surface);box-shadow:inset 0 0 0 1px var(--line);flex:1 1 180px;max-width:260px;color:var(--fg-3)}
.mini:focus-within{box-shadow:inset 0 0 0 1px var(--fg-4)}
.mini input{border:0;outline:0;background:none;min-width:0;flex:1;font-size:13.5px;color:var(--fg)}
.fbar .cnt{margin-left:auto;font:12px var(--mono);color:var(--fg-3)}

/* entries — sections separated by dashed rules, numbered inline titles (Beautiful UI), nested stage for cost/gain */
.elist{display:flex;flex-direction:column}
.entry{padding:30px 0 32px;border-bottom:1px dashed var(--line-2);scroll-margin-top:calc(var(--hh) + 76px)}
.eh{display:flex;align-items:baseline;gap:12px}
.en{font:500 13px var(--mono);color:var(--fg-4);min-width:22px;flex:none}
.eh h3{margin:0;flex:1;font-size:19px;line-height:1.45;font-weight:600;letter-spacing:-.015em;text-wrap:pretty}
.eh h3 a:hover{text-decoration:underline;text-decoration-color:var(--fg-4);text-underline-offset:4px}
.cp{width:30px;height:30px;border-radius:8px;display:grid;place-items:center;color:var(--fg-4);opacity:0;transition:opacity .15s,background .15s,color .15s;align-self:center}
.entry:hover .cp,.cp:focus-visible{opacity:1}.cp:hover{background:var(--tray);color:var(--fg)}
.cp svg{width:15px;height:15px}
.meta-row{display:flex;flex-wrap:wrap;gap:6px;margin:12px 0 0 34px}
.tg,.rate,.gd{display:inline-flex;align-items:center;gap:6px;height:24px;padding:0 9px;border-radius:7px;font-size:12px;white-space:nowrap;color:var(--fg-2);background:var(--surface);box-shadow:inset 0 0 0 1px var(--line)}
.tg.z{color:var(--fg-3)}
.tg.chl{color:var(--fg)}.tg.chl:hover{box-shadow:inset 0 0 0 1px var(--fg-4)}
.tg.warn{color:var(--warn);box-shadow:inset 0 0 0 1px color-mix(in srgb,var(--warn) 30%,transparent)}
.rate{font-weight:500;color:var(--fg)}
.rate.r3{background:var(--inv);color:var(--inv-fg);box-shadow:none}
.rate.r1{color:var(--fg-2);font-weight:400}
.gd i{width:6px;height:6px;border-radius:50%;background:var(--c)}
.gd.gA{color:var(--a);background:var(--a-bg);box-shadow:none;font-weight:500}.gd.gA i{background:var(--a)}
.gd.gB{color:var(--b);background:var(--b-bg);box-shadow:none;font-weight:500}.gd.gB i{background:var(--b)}
.human{position:relative;margin:16px 0 0 34px;padding:13px 16px 13px 18px;border-radius:12px;background:var(--surface);box-shadow:0 0 0 1px var(--line),var(--sh-1);font-size:15px;line-height:1.75;color:var(--fg);text-wrap:pretty}
.human::before{content:"";position:absolute;left:0;top:12px;bottom:12px;width:2px;border-radius:2px;background:linear-gradient(var(--a),var(--b))}
.human .lb{display:inline-block;margin-right:10px;font-size:12px;font-weight:600;color:var(--fg-3)}
.cg{display:grid;grid-template-columns:1fr 1fr;gap:6px;margin:10px 0 0 34px;padding:6px;border-radius:14px;background:var(--tray);box-shadow:inset 0 0 0 1px var(--line)}
.col{padding:12px 14px;border-radius:9px;background:var(--surface);box-shadow:0 0 0 1px var(--line);min-width:0}
.col .k{display:flex;align-items:baseline;gap:8px;font-size:12.5px;font-weight:600;color:var(--fg);margin-bottom:5px}
.col .k span{font-weight:400;color:var(--fg-3);font-size:12px}
.col .v{font-size:14px;line-height:1.75;color:var(--fg-2);overflow-wrap:anywhere;text-wrap:pretty}
.note{display:grid;grid-template-columns:auto 1fr;gap:12px;margin:14px 0 0 34px;font-size:14px;line-height:1.75;color:var(--fg-2)}
.note .k{font-size:12.5px;font-weight:600;color:var(--fg-3);line-height:1.9}
.src{margin:12px 0 0 34px}
.src summary{display:inline-flex;align-items:center;gap:6px;list-style:none;cursor:pointer;font-size:13px;color:var(--fg-3);padding:4px 8px 4px 4px;border-radius:7px;transition:color .15s,background .15s}
.src summary::-webkit-details-marker{display:none}
.src summary:hover{color:var(--fg);background:var(--tray)}
.src summary svg{width:13px;height:13px;transition:transform .2s var(--ease)}
.src[open] summary svg{transform:rotate(90deg)}
.src .cnt{font:11px var(--mono);color:var(--fg-4);margin-left:4px}
.src .body{margin-top:8px;padding:12px 14px;border-radius:10px;background:var(--sunk);box-shadow:inset 0 0 0 1px var(--line);font-size:13px;line-height:1.75;color:var(--fg-2);overflow-wrap:anywhere}
.src-list{margin:0;padding-left:18px}.src-item+.src-item{margin-top:6px}
.src-a{font-family:var(--mono);font-size:12px;color:var(--b)!important;text-decoration:none!important}
.src-a:hover{text-decoration:underline!important}
.entry.flash{animation:flash 1.6s var(--ease)}
@keyframes flash{0%,30%{background:color-mix(in srgb,var(--b) 7%,transparent)}100%{background:transparent}}
/* compact entry inside the hero window */
.entry.compact{padding:0;border:0}
.entry.compact .eh h3{font-size:18px}
.entry.compact .meta-row,.entry.compact .human,.entry.compact .cg{margin-left:0}
.entry.compact .cg{grid-template-columns:1fr}
.entry.compact .col .v{font-size:13.5px}
.empty{padding:56px 0;text-align:center;color:var(--fg-3);font-size:14px}
.pager{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin-top:40px}
.pg{display:flex;flex-direction:column;gap:2px;padding:16px 18px;border-radius:14px;background:var(--surface);box-shadow:0 0 0 1px var(--line),var(--sh-1);transition:box-shadow .15s}
.pg:hover{box-shadow:0 0 0 1px var(--line-2),var(--sh-2)}
.pg small{font-size:12.5px;color:var(--fg-3)}.pg b{font-size:15px;font-weight:600}
.pg.nx{text-align:right;grid-column:2}
.srcline{margin:22px 0 0;font-size:12.5px;color:var(--fg-3)}
.srcline a{text-decoration:underline;text-decoration-color:var(--fg-4);text-underline-offset:3px}
/* hatch gutters on reading pages (Beautiful UI) */
body:has(.cpage,.dpage) .rails{background:repeating-linear-gradient(-45deg,var(--hatch) 0 1px,transparent 1px 9px);-webkit-mask:linear-gradient(90deg,#000 calc(50% - var(--max)/2),transparent calc(50% - var(--max)/2),transparent calc(50% + var(--max)/2),#000 calc(50% + var(--max)/2));mask:linear-gradient(90deg,#000 calc(50% - var(--max)/2),transparent calc(50% - var(--max)/2),transparent calc(50% + var(--max)/2),#000 calc(50% + var(--max)/2))}
body:has(.cpage,.dpage) .rails::before,body:has(.cpage,.dpage) .rails::after{display:none}

/* secondary pages */
.shead{padding-top:56px;padding-bottom:72px}
.eyebrow{margin:0 0 12px;font-size:13px;color:var(--fg-3);font-weight:500}
.shead h1{margin:0;font-size:clamp(30px,3.6vw,44px);line-height:1.15;font-weight:600;letter-spacing:-.03em}
.shead .lede{font-size:16px}
.shead .hsearch{max-width:640px}
.fpanel{margin-top:22px;border-radius:16px;background:var(--surface);box-shadow:0 0 0 1px var(--line),var(--sh-1);overflow:hidden}
.frow{display:grid;grid-template-columns:88px 1fr;align-items:center;gap:12px;padding:8px 14px;border-bottom:1px solid var(--line)}
.frow:last-child{border-bottom:0}
.frow label{font-size:12.5px;font-weight:500;color:var(--fg-3)}
.ops{display:flex;flex-wrap:wrap;gap:4px}
.ops select{height:32px;padding:0 10px;border-radius:8px;border:0;background:var(--tray);box-shadow:inset 0 0 0 1px var(--line);max-width:100%}
.ops .chip.on{background:var(--inv);color:var(--inv-fg);box-shadow:none}
.ops .chip.on .n{color:inherit;opacity:.6}
.sres{margin:26px 0 0}.meta{font-size:13px;color:var(--fg-3);margin:0}.meta b{color:var(--fg);font-family:var(--mono)}
.sgrid{display:flex;flex-direction:column;border-top:1px dashed var(--line-2);margin-top:12px}
.lmore{display:flex;justify-content:center;margin-top:28px}
.lmore .btn{height:40px;background:var(--surface);box-shadow:inset 0 0 0 1px var(--line-2)}
.shead .sh{margin:40px 0 14px}
.rgroup{margin-bottom:36px}
.rgroup h3{font-size:13px;font-weight:500;color:var(--fg-3);margin:0 0 10px}
.rlist{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:1px;background:var(--line);border-radius:14px;overflow:hidden;box-shadow:0 0 0 1px var(--line)}
.rl{display:flex;justify-content:space-between;align-items:baseline;gap:12px;padding:12px 16px;background:var(--surface);font-size:13.5px;transition:background .15s}
.rl b{font-weight:500;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.rl small{font:11px var(--mono);color:var(--fg-4)}
.rl:hover{background:var(--sunk)}
.rl[hidden],.rgroup[hidden],.gl[hidden]{display:none}
.glist{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:1px;background:var(--line);border-radius:16px;overflow:hidden;box-shadow:0 0 0 1px var(--line)}
.gl{margin:0;padding:18px 20px;background:var(--surface)}
.gl dt{font-weight:600;font-size:15px}
.gl dd{margin:6px 0 0;font-size:14px;line-height:1.75;color:var(--fg-2)}

/* long-form reading */
.dpage{display:grid;grid-template-columns:minmax(0,1fr) 220px;gap:64px;padding-top:40px;padding-bottom:88px}
.dpage>article{max-width:720px;min-width:0}
.crumb{display:flex;gap:8px;font:12px var(--mono);color:var(--fg-3);margin-bottom:22px;flex-wrap:wrap}
.crumb a{color:var(--fg-2)}.crumb a:hover{color:var(--fg)}
.prose{font-size:15.5px;line-height:1.85;color:var(--fg-2);overflow-wrap:anywhere}
.prose h1{font-size:clamp(28px,3.4vw,40px);line-height:1.2;letter-spacing:-.03em;color:var(--fg);margin:0 0 20px;font-weight:600}
.prose h2{font-size:22px;letter-spacing:-.02em;color:var(--fg);margin:48px 0 12px;padding-top:24px;border-top:1px dashed var(--line-2);font-weight:600}
.prose h3{font-size:17px;color:var(--fg);margin:30px 0 8px;font-weight:600}
.prose strong{color:var(--fg)}
.prose blockquote{margin:16px 0;padding:12px 16px;border-radius:12px;background:var(--tray);box-shadow:inset 0 0 0 1px var(--line)}
.prose blockquote p{margin:0}
.prose ul,.prose ol{padding-left:22px}.prose li+li{margin-top:4px}
.prose code{background:var(--tray);padding:1px 5px;border-radius:5px;box-shadow:inset 0 0 0 1px var(--line)}
.prose pre{background:var(--sunk);padding:14px;border-radius:12px;overflow:auto;box-shadow:inset 0 0 0 1px var(--line)}
.prose pre code{box-shadow:none;background:none;padding:0}
.tw{overflow:auto;margin:18px 0;border-radius:12px;box-shadow:0 0 0 1px var(--line)}
.prose table{border-collapse:collapse;width:100%;font-size:13.5px;line-height:1.6}
.prose th,.prose td{padding:9px 12px;border-bottom:1px solid var(--line);text-align:left;vertical-align:top}
.prose th{background:var(--sunk);color:var(--fg);font-weight:600;white-space:nowrap}
.prose tr:last-child td{border-bottom:0}
.alist{display:flex;flex-wrap:wrap;gap:8px;margin:12px 0 18px}
.alist .btn,.dmeta .btn{text-decoration:none;color:var(--fg)}
.dmeta{display:flex;gap:8px;margin-top:40px;flex-wrap:wrap}
.dtoc{position:sticky;top:calc(var(--hh) + 24px);align-self:start;max-height:calc(100vh - var(--hh) - 48px);overflow:auto;font-size:13px}
.dtoc .lab{font-weight:500;color:var(--fg-3);margin:0 0 10px}
.dtoc a{display:block;padding:4px 0 4px 12px;border-left:1px solid var(--line);color:var(--fg-3);line-height:1.5;transition:color .15s,border-color .15s}
.dtoc a.h3{padding-left:24px}
.dtoc a:hover{color:var(--fg)}.dtoc a.on{color:var(--fg);border-left-color:var(--fg)}
.loading{display:flex;flex-direction:column;align-items:center;gap:14px;padding:120px 0;color:var(--fg-3);font-size:13.5px}
.spin{width:22px;height:22px;border-radius:50%;border:2px solid var(--line-2);border-top-color:var(--fg);animation:spin .8s linear infinite}
@keyframes spin{to{transform:rotate(360deg)}}
.fade{animation:fadein .4s var(--ease)}

/* footer */
.foot{border-top:1px solid var(--line);padding:40px 0 56px;font-size:13px;color:var(--fg-3);background:var(--bg)}
.fgrid{display:grid;grid-template-columns:minmax(0,1.6fr) 1fr;gap:48px}
.foot p{margin:0 0 8px;line-height:1.75;max-width:60ch}
.foot a{color:var(--fg-2);text-decoration:underline;text-decoration-color:var(--fg-4);text-underline-offset:3px}
.fl{display:flex;align-items:center;gap:9px;color:var(--fg)}.fl b{font-weight:600}
.flinks{display:flex;flex-direction:column;gap:8px;align-items:flex-start}
.flinks a{text-decoration:none}.flinks a:hover{color:var(--fg)}
.toast{position:fixed;left:50%;bottom:28px;transform:translate(-50%,16px);opacity:0;z-index:60;padding:10px 16px;border-radius:999px;background:var(--inv);color:var(--inv-fg);font-size:13px;box-shadow:var(--sh-2);transition:opacity .2s,transform .3s var(--ease);pointer-events:none}
.toast.show{opacity:1;transform:translate(-50%,0)}
.bottom{display:none}

/* responsive */
@media (max-width:1100px){
  .tabs a{padding:6px 8px}.sbtn{width:auto}.sbtn span{display:none}
  .tray{grid-template-columns:repeat(2,minmax(0,1fr))}
  .hgrid{gap:40px}
}
@media (max-width:960px){
  .hgrid{grid-template-columns:minmax(0,1fr)}.hwin{max-width:640px}
  .cgrid{grid-template-columns:repeat(2,minmax(0,1fr))}
  .two{grid-template-columns:1fr;gap:56px}
  .cpage{grid-template-columns:1fr;gap:0}.side{display:none}
  .mchap{display:block;margin-bottom:16px}
  .mchap select{width:100%;height:40px;padding:0 12px;border-radius:10px;border:0;background:var(--surface);box-shadow:inset 0 0 0 1px var(--line)}
  .dpage{grid-template-columns:1fr}.dtoc{display:none}
  .rlist{grid-template-columns:repeat(2,minmax(0,1fr))}
}
@media (max-width:720px){
  :root{--gut:20px;--hh:56px}
  .tabs{display:none}.logo{margin-right:auto}.sbtn{margin-left:0}
  .hero{padding:36px 0 56px}.hero h1{font-size:27px;letter-spacing:-.02em}
  .lede{font-size:15.5px}
  .btn{height:42px}
  .win{height:460px}.hwin{padding:14px 0 0 10px}
  .sec{padding:56px 0 60px}
  .tray,.cgrid,.glist,.rlist{grid-template-columns:1fr}
  .sh.row{flex-direction:column;align-items:flex-start;gap:16px}
  .tv{min-height:0}
  .cell{min-height:0}
  .meta-row,.human,.cg,.note,.src{margin-left:0}
  .cg{grid-template-columns:1fr}
  .eh h3{font-size:17.5px}
  .fbar{position:static;margin:18px 0 0;padding:0 0 14px;gap:8px;background:none;backdrop-filter:none;-webkit-backdrop-filter:none}
  .mini{max-width:none;flex-basis:100%}
  .fbar .seg{overflow-x:auto}
  .pager{grid-template-columns:1fr}.pg.nx{grid-column:auto}
  .fgrid{grid-template-columns:1fr;gap:20px}
  .frow{grid-template-columns:1fr;gap:6px}
  body{padding-bottom:64px}
  .bottom{display:flex;position:fixed;left:0;right:0;bottom:0;z-index:40;height:calc(58px + env(safe-area-inset-bottom));padding-bottom:env(safe-area-inset-bottom);background:color-mix(in srgb,var(--bg) 88%,transparent);backdrop-filter:blur(14px);-webkit-backdrop-filter:blur(14px);border-top:1px solid var(--line)}
  .bottom a{flex:1;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:3px;font-size:11px;color:var(--fg-3)}
  .bottom a.on{color:var(--fg)}
  .bottom svg{width:20px;height:20px}
  .toast{bottom:80px}
}

.cell.fill{grid-column:span 2;display:flex;flex-direction:column;background:var(--sunk);background-image:radial-gradient(var(--dot) 1px,transparent 1px);background-size:8px 8px}
.cell.fill b{font-size:16px}.cell.fill small{-webkit-line-clamp:3;max-width:34em}
.cell.fill .cf{gap:8px;margin-top:auto;padding-top:14px}
.chip:disabled{opacity:.38;cursor:not-allowed}
@media (max-width:960px){.cell.fill{grid-column:1/-1}}

/* ---------- language switcher + notes (v9) ---------- */
.lang-b{position:relative;width:auto;padding:0 6px 0 8px;cursor:pointer}
.lang-v{display:inline-flex;align-items:center;gap:4px;pointer-events:none;font-size:12.5px;font-weight:600;letter-spacing:.01em;color:inherit}
.lang-v svg{width:16px;height:16px;fill:none;stroke:currentColor;stroke-width:1.7;stroke-linecap:round;stroke-linejoin:round}
.lang-v svg.cv{width:12px;height:12px;opacity:.6}
.lang-v b{font-weight:600;min-width:1.2em;text-align:center}
.lang-b select{position:absolute;inset:0;width:100%;height:100%;opacity:0;cursor:pointer;font-size:16px;border:0;-webkit-appearance:none;appearance:none}
.lang-b:focus-within{outline:2px solid var(--fg);outline-offset:1px}
.lnote{margin-top:14px;padding:10px 14px;border-radius:10px;background:var(--tray);box-shadow:inset 0 0 0 1px var(--line);font-size:13px;line-height:1.6;color:var(--fg-2)}
.lnote p{margin:0}
.lnote a{color:var(--fg);text-decoration:underline;text-underline-offset:2px}
.notes .lnote{margin-top:16px}
html:not([lang^="zh"]) .human,html:not([lang^="zh"]) .cg .v{word-break:normal;overflow-wrap:anywhere}
@media (max-width:1100px){ html:not([lang^="zh"]):not([lang="ja"]):not([lang="ko"]) .tabs a{padding:6px 6px;font-size:13px} }
@media (max-width:720px){
  .logo{min-width:0;flex:1 1 auto}.logo .wm{overflow:hidden;text-overflow:ellipsis;min-width:0}
  .top a.icon[href*="github.com"]{display:none}
  .lang-v svg.cv{display:none}.lang-b{padding:0 6px}
}

/* review fixes 2026-10-15: natural-height cost/gain cards, ~68ch measure, hide empty filters, 32px+ tap targets */
.cg{align-items:start}
.entry>.human,.entry>.note{max-width:68ch}
.entry>.cg{max-width:calc(68ch + 34px)}
.entry .src .body{max-width:72ch}
.chip[hidden],.fpanel [hidden]{display:none!important}
@media (max-width:760px){
  .chip{height:auto;min-height:34px}
  .meta-row .tg,.meta-row .rate,.meta-row .gd{min-height:26px;display:inline-flex;align-items:center}
  .meta-row a.tg,.crumbs a,.cp,.ops .chip,.fpanel button{min-height:34px;min-width:34px;display:inline-flex;align-items:center}
  .entry>.cg{max-width:none}
  .src-a,.xr,.flinks a,.srcline a{display:inline-block;padding:6px 0}
  .mini{height:40px}
}