:root{--bg:#fff;--header-bg:#ffffffc7;--text:#172019;--muted:#55605a;--subtle:#69716b;--line:#e1e5e1;--surface:#f3f4f1;--surface-alt:#edf0ec;--surface-hover:#e5e9e4;--accent:#187252;--accent-soft:#85c5a8;--inverse-bg:#172019;--inverse-text:#fff;--card-border:#17201914;--menu-shadow:0 16px 42px #17201929;--shell-width:1200px;--content-width:800px;background:var(--bg);color:var(--text);color-scheme:light;font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif}:root[data-theme=dark]{--bg:#101310;--header-bg:#101310c7;--text:#f1f4f1;--muted:#b3bcb6;--subtle:#929c95;--line:#2d342f;--surface:#1a1f1b;--surface-alt:#1f2520;--surface-hover:#273029;--accent:#72c99f;--accent-soft:#8bd8b2;--inverse-bg:#edf1ed;--inverse-text:#101310;--card-border:#ffffff14;--menu-shadow:0 18px 48px #00000070;color-scheme:dark}@media (prefers-color-scheme:dark){:root:not([data-theme=light]){--bg:#101310;--header-bg:#101310c7;--text:#f1f4f1;--muted:#b3bcb6;--subtle:#929c95;--line:#2d342f;--surface:#1a1f1b;--surface-alt:#1f2520;--surface-hover:#273029;--accent:#72c99f;--accent-soft:#8bd8b2;--inverse-bg:#edf1ed;--inverse-text:#101310;--card-border:#ffffff14;--menu-shadow:0 18px 48px #00000070;color-scheme:dark}}*{box-sizing:border-box}:root:lang(zh){font-family:PingFang SC,Hiragino Sans GB,Microsoft YaHei,Inter,ui-sans-serif,system-ui,sans-serif}::view-transition-old(root),::view-transition-new(root){mix-blend-mode:normal;animation:none}:root[data-theme-transition=expand]::view-transition-new(root){z-index:2;animation:.92s cubic-bezier(.65,0,.35,1) both theme-expand}:root[data-theme-transition=contract]::view-transition-old(root){z-index:2;animation:.92s cubic-bezier(.65,0,.35,1) both theme-contract}:root[data-theme-transition] *,:root[data-theme-transition] :before,:root[data-theme-transition] :after{transition:none!important}@keyframes theme-expand{0%{clip-path:circle(0 at var(--theme-x) var(--theme-y))}to{clip-path:circle(var(--theme-radius) at var(--theme-x) var(--theme-y))}}@keyframes theme-contract{0%{clip-path:circle(var(--theme-radius) at var(--theme-x) var(--theme-y))}to{clip-path:circle(0 at var(--theme-x) var(--theme-y))}}body{background:var(--bg);min-width:320px;margin:0;padding-top:72px;transition:background-color .2s,color .2s}a{color:inherit;text-underline-offset:4px;text-decoration-thickness:1px}a:focus-visible{outline:2px solid var(--accent);outline-offset:3px}.site-header,.mobile-menu-inner,main,footer{width:min(var(--shell-width), calc(100% - 56px));margin:0 auto}.site-header-shell{background:var(--header-bg);z-index:20;backdrop-filter:blur(14px);position:fixed;top:0;left:0;right:0}.site-header{border-bottom:1px solid var(--line);grid-template-columns:minmax(180px,1fr) auto minmax(180px,1fr);align-items:center;gap:24px;min-height:72px;display:grid}.wordmark{letter-spacing:-.02em;white-space:nowrap;justify-self:start;align-items:center;gap:10px;font-size:.94rem;font-weight:750;text-decoration:none;display:inline-flex}.wordmark-mark{background:var(--surface);border:1px solid var(--line);color:var(--text);letter-spacing:-.06em;border-radius:50%;justify-content:center;align-items:center;width:27px;height:27px;font-family:Georgia,Times New Roman,serif;font-size:.59rem;font-weight:400;transition:background-color .18s,border-color .18s;display:inline-flex}.wordmark:hover .wordmark-mark{background:var(--surface-hover);border-color:var(--subtle)}.desktop-navigation{justify-content:center;align-items:center;gap:24px;display:flex}.desktop-navigation a{color:var(--subtle);letter-spacing:.015em;font-size:.83rem;font-weight:600;text-decoration:none;transition:color .16s;position:relative}.desktop-navigation a:hover{color:var(--text);text-decoration:underline}.desktop-navigation a[aria-current=page]{color:var(--text);font-weight:750;text-decoration:none}.desktop-navigation a[aria-current=page]:after{background:var(--accent);content:"";width:16px;height:2px;position:absolute;bottom:-10px;left:50%;transform:translate(-50%)}.header-utilities{justify-self:end;align-items:center;gap:10px;display:flex}.header-divider{background:var(--line);width:1px;height:18px;margin-right:2px;display:block}.language-switch{border:1px solid var(--line);color:var(--subtle);white-space:nowrap;border-radius:999px;justify-content:center;align-items:center;min-width:38px;height:34px;padding:0 10px;font-size:.72rem;font-weight:750;text-decoration:none;transition:background-color .16s,border-color .16s,color .16s;display:inline-flex}.language-switch:hover{background:var(--surface);border-color:var(--subtle);color:var(--text)}.theme-menu-root{position:relative}.theme-menu-trigger{appearance:none;background:var(--bg);border:1px solid var(--line);color:var(--text);cursor:pointer;border-radius:50%;justify-content:center;align-items:center;width:34px;height:34px;padding:0;transition:background-color .16s,border-color .16s,transform .16s;display:flex;position:relative;overflow:hidden}.theme-menu-trigger:hover,.theme-menu-trigger[aria-expanded=true]{background:var(--surface);border-color:var(--subtle)}.theme-menu-trigger:active{transform:scale(.94)}.theme-menu-trigger:focus-visible,.theme-menu button:focus-visible,.mobile-menu-trigger:focus-visible,.mobile-theme-options button:focus-visible{outline:2px solid var(--accent);outline-offset:2px}.theme-menu-trigger svg{width:17px;height:17px}.theme-menu-trigger [data-theme-trigger-icon]{opacity:0;justify-content:center;align-items:center;transition:opacity .22s,transform .34s cubic-bezier(.2,.8,.2,1);display:flex;position:absolute;transform:rotate(70deg)scale(.45)}:root[data-theme=light] .theme-menu-trigger [data-theme-trigger-icon=light],:root[data-theme=dark] .theme-menu-trigger [data-theme-trigger-icon=dark],:root[data-theme=system] .theme-menu-trigger [data-theme-trigger-icon=system]{opacity:1;transform:rotate(0)scale(1)}.theme-menu{background:var(--bg);border:1px solid var(--line);box-shadow:var(--menu-shadow);opacity:0;pointer-events:none;transform-origin:100% 0;border-radius:10px;min-width:156px;padding:6px;transition:opacity .14s,transform .18s cubic-bezier(.2,.8,.2,1);position:absolute;top:calc(100% + 9px);right:0;transform:translateY(-7px)scale(.96)}.theme-menu[data-state=open]{opacity:1;pointer-events:auto;transform:translateY(0)scale(1)}.theme-menu button{appearance:none;color:var(--text);cursor:pointer;font:inherit;opacity:0;text-align:left;background:0 0;border:0;border-radius:6px;grid-template-columns:18px 1fr 16px;align-items:center;gap:10px;width:100%;padding:9px 10px;font-size:.82rem;transition:background-color .13s,opacity .14s,transform .16s;display:grid;transform:translateY(-3px)}.theme-menu[data-state=open] button{opacity:1;transform:translateY(0)}.theme-menu[data-state=open] button:first-child{transition-delay:20ms}.theme-menu[data-state=open] button:nth-child(2){transition-delay:40ms}.theme-menu[data-state=open] button:nth-child(3){transition-delay:60ms}.theme-menu button:hover,.theme-menu button:focus-visible{background:var(--surface)}.theme-menu svg,.theme-menu-trigger svg,.mobile-menu-trigger svg,.mobile-theme-options svg{fill:none;stroke:currentColor;stroke-linecap:round;stroke-linejoin:round;stroke-width:1.8px}.theme-menu svg{width:17px;height:17px}.theme-option-check{color:var(--accent);opacity:0;transition:opacity .15s,transform .2s cubic-bezier(.2,.8,.2,1);transform:scale(.65)}.theme-menu button[aria-checked=true] .theme-option-check{opacity:1;transform:scale(1)}.mobile-menu-trigger{appearance:none;background:var(--bg);border:1px solid var(--line);color:var(--text);cursor:pointer;border-radius:50%;justify-content:center;align-items:center;width:34px;height:34px;padding:0;transition:background-color .16s,border-color .16s,transform .16s;display:none;position:relative}.mobile-menu-trigger:hover,.mobile-menu-trigger[aria-expanded=true]{background:var(--surface);border-color:var(--subtle)}.mobile-menu-trigger:active{transform:scale(.94)}.mobile-menu-trigger svg{width:18px;height:18px;transition:opacity .18s,transform .22s cubic-bezier(.2,.8,.2,1);position:absolute}.mobile-menu-trigger [data-mobile-menu-icon=open]{opacity:1;transform:rotate(0)scale(1)}.mobile-menu-trigger [data-mobile-menu-icon=close]{opacity:0;transform:rotate(-55deg)scale(.6)}.mobile-menu-trigger[aria-expanded=true] [data-mobile-menu-icon=open]{opacity:0;transform:rotate(55deg)scale(.6)}.mobile-menu-trigger[aria-expanded=true] [data-mobile-menu-icon=close]{opacity:1;transform:rotate(0)scale(1)}.mobile-menu{display:none}.sr-only{clip:rect(0, 0, 0, 0);white-space:nowrap;width:1px;height:1px;margin:-1px;padding:0;position:absolute;overflow:hidden}main{min-height:calc(100vh - 183px)}footer{color:var(--subtle);border-top:1px solid var(--line);justify-content:space-between;align-items:center;min-height:97px;font-size:.81rem;display:flex}.footer-links{gap:18px;display:flex}.footer-links a{align-items:center;text-decoration:none;display:inline-flex}.footer-links a:hover{color:var(--text);text-decoration:underline}.footer-links a svg{stroke-width:1.8px;width:14px;height:14px}.footer-links a .footer-github-icon{fill:currentColor;stroke:none;margin-right:5px}.footer-links a .footer-external-icon{margin-left:4px}.eyebrow{color:var(--accent);letter-spacing:.13em;text-transform:uppercase;font-size:.72rem;font-weight:750}.page{max-width:var(--content-width);padding:clamp(52px,7vw,88px) 0}.page h1,.display{letter-spacing:-.025em;margin:14px 0 22px;font-family:DM Serif Display,Georgia,Times New Roman,serif;font-size:clamp(2.35rem,3.5vw,3.6rem);font-weight:400;line-height:1.04}:root:lang(zh) .page h1,:root:lang(zh) .display{letter-spacing:-.03em;font-family:LXGW WenKai,Songti SC,STSong,SimSun,Georgia,serif;font-size:clamp(2.25rem,3.4vw,3.2rem);line-height:1.18}.page h2{letter-spacing:-.015em;margin:0 0 12px;font-family:DM Serif Display,Georgia,Times New Roman,serif;font-size:clamp(1.55rem,2.25vw,2.15rem);font-weight:400;line-height:1.18}:root:lang(zh) .page h2{letter-spacing:-.02em;font-family:LXGW WenKai,Songti SC,STSong,SimSun,Georgia,serif;line-height:1.26}.page h3{margin:0;font-size:1rem;line-height:1.35}.page p{color:var(--muted);max-width:670px;font-size:1.06rem;line-height:1.8}.page p+p{margin-top:16px}.page-intro{grid-template-columns:1fr minmax(260px,.8fr);align-items:end;gap:48px;display:grid}.page-intro h1{margin:14px 0 0;font-size:clamp(2rem,4vw,3.1rem)}.page-intro .lead{margin:0;font-size:.88rem;line-height:1.7}.button-link{background:var(--text);border:1px solid var(--text);color:var(--bg);border-radius:6px;justify-content:center;align-items:center;gap:6px;min-height:44px;margin-top:17px;padding:0 16px;font-size:.9rem;font-weight:700;text-decoration:none;transition:background-color .18s,border-color .18s,color .18s,transform .18s;display:inline-flex}.button-link svg{stroke-width:1.8px;width:16px;height:16px;margin-left:0;transition:transform .18s}.button-link:hover{background:var(--accent);border-color:var(--accent);color:var(--bg);transform:translateY(-1px)}.button-link:hover svg{transform:translate(2px)}.button-link:active{transform:translateY(0)}.button-link:focus-visible{outline:2px solid var(--accent);outline-offset:3px}.button-link--quiet{border-color:var(--line);color:var(--text);background:0 0;margin-left:8px}.button-link--quiet:hover{background:var(--surface);border-color:var(--subtle);color:var(--text)}.rule{border:0;border-top:1px solid var(--line);margin:70px 0 0}.section-heading{justify-content:space-between;align-items:baseline;gap:18px;margin-bottom:24px;display:flex}.section-heading a{color:var(--accent);white-space:nowrap;font-size:.86rem;font-weight:700}.list{margin:24px 0 0;padding:0;list-style:none}.list li{border-bottom:1px solid var(--line);justify-content:space-between;gap:20px;padding:18px 0;display:flex}.list span{color:var(--subtle);white-space:nowrap}.muted{color:var(--subtle);font-size:.92rem}@media (prefers-reduced-motion:reduce){*,:before,:after{scroll-behavior:auto!important;transition-duration:0s!important;transition-delay:0s!important;animation-duration:.01ms!important;animation-iteration-count:1!important}}@media (width<=820px){body{padding-top:64px}.site-header{grid-template-columns:minmax(0,1fr) auto;gap:16px;min-height:64px}.desktop-navigation,.desktop-theme-menu,.header-divider{display:none}.header-utilities{gap:8px}.mobile-menu-trigger{display:flex}.mobile-menu{background:var(--bg);border-bottom:1px solid var(--line);box-shadow:var(--menu-shadow);opacity:0;pointer-events:none;max-height:calc(100vh - 64px);transition:opacity .18s,transform .22s cubic-bezier(.2,.8,.2,1);display:block;position:absolute;top:64px;left:0;right:0;overflow-y:auto;transform:translateY(-8px)}.mobile-menu[hidden]{display:none}.mobile-menu[data-state=open]{opacity:1;pointer-events:auto;transform:translateY(0)}.mobile-menu-inner{padding:12px 0 20px}.mobile-navigation{display:grid}.mobile-navigation a{border-bottom:1px solid var(--line);color:var(--subtle);align-items:center;min-height:48px;font-size:.94rem;font-weight:650;text-decoration:none;transition:background-color .16s,color .16s;display:flex;position:relative}.mobile-navigation a:after{background:var(--accent);content:"";width:0;height:2px;margin-left:auto;transition:width .2s cubic-bezier(.2,.8,.2,1)}.mobile-navigation a:hover{color:var(--text)}.mobile-navigation a[aria-current=page]{color:var(--text);font-weight:750}.mobile-navigation a[aria-current=page]:after{width:20px}.mobile-theme{padding-top:20px}.mobile-theme-label{color:var(--subtle);letter-spacing:.12em;text-transform:uppercase;margin-bottom:12px;font-size:.72rem;font-weight:750;display:block}.mobile-theme-options{grid-template-columns:repeat(3,minmax(0,1fr));gap:8px;display:grid}.mobile-theme-options button{appearance:none;border:1px solid var(--line);color:var(--subtle);cursor:pointer;font:inherit;text-align:left;background:0 0;border-radius:2px;grid-template-columns:16px minmax(0,1fr) 14px;align-items:center;gap:5px;min-height:44px;padding:0 8px;font-size:.72rem;font-weight:650;transition:background-color .16s,border-color .16s,color .16s;display:grid}.mobile-theme-options button:hover{background:var(--surface);border-color:var(--subtle);color:var(--text)}.mobile-theme-options button[aria-checked=true]{border-color:var(--accent);color:var(--text)}.mobile-theme-options button[aria-checked=true] .theme-option-check{opacity:1;transform:scale(1)}.mobile-theme-options svg{width:16px;height:16px}.mobile-theme-options .theme-option-check{width:14px;height:14px}}@media (width<=360px){.mobile-theme-options{grid-template-columns:repeat(2,minmax(0,1fr))}.mobile-theme-options button:last-child{grid-column:1/-1}}@media (width<=430px){.language-switch{padding-inline:8px}}@media (width<=620px){.site-header,.mobile-menu-inner,main,footer{width:min(100% - 32px, var(--shell-width))}.page{padding:64px 0}.page-intro{grid-template-columns:1fr;align-items:start;gap:20px}footer{flex-direction:column;justify-content:center;align-items:flex-start;gap:12px;min-height:110px}.list li{flex-direction:column;align-items:flex-start;gap:5px}.button-link--quiet{margin-left:4px}}