/* 這些值是 web/src/index.css :root 的複製品：說明頁刻意單檔自足、不進 build，
   所以不能 import。改其中一邊就要同步改另一邊。 */
:root{color-scheme:dark;--bg:#101110;--text:#f5f5f2;--muted:#a2a5a0;--line:#363733;--soft-line:#292b27;--font:-apple-system,BlinkMacSystemFont,'Segoe UI','Noto Sans TC',Arial,sans-serif;--mono:'SFMono-Regular',Consolas,'Liberation Mono',monospace;--ease:cubic-bezier(.22,.68,0,1)}
*{box-sizing:border-box}
html{scroll-behavior:smooth;scroll-padding-top:100px}
body{margin:0;background:var(--bg);color:var(--text);font:16px/1.75 var(--font);-webkit-font-smoothing:antialiased}
body,button,a{-webkit-tap-highlight-color:transparent}
::selection{background:var(--text);color:var(--bg)}
a{color:inherit;text-decoration:none}
button{font:inherit;color:inherit;cursor:pointer}
button:disabled{cursor:default}
button,a{touch-action:manipulation}
button:focus-visible,a:focus-visible,summary:focus-visible,[tabindex]:focus-visible{outline:2px solid var(--text);outline-offset:2px}
button{border:0;background:none}
[hidden]{display:none!important}
svg{display:block}
h1,h2,h3,p,ol,dl{margin:0}
h1,h2,h3{font-weight:500}
p{color:var(--muted)}
h2{font-size:clamp(30px,3.3vw,48px);line-height:1.4;letter-spacing:-.05em;text-wrap:balance}
h3{font-size:22px;line-height:1.5;letter-spacing:-.035em}
.shell{width:min(1300px,calc(100% - 112px));margin-inline:auto}
.mono{font-family:var(--mono);font-size:12px;letter-spacing:.07em}
.skip-link{position:fixed;left:20px;top:20px;padding:12px 18px;background:var(--text);color:var(--bg);z-index:100;transform:translateY(-170%)}
.skip-link:focus{transform:translateY(0)}
.reading-progress{height:2px;position:fixed;top:0;left:0;right:0;z-index:50;pointer-events:none}
.reading-progress span{display:block;height:100%;background:var(--text);transform:scaleX(0);transform-origin:left}
.site-header{height:108px;display:flex;align-items:center;justify-content:space-between;gap:24px}
.logo{display:inline-flex;align-items:center;gap:12px;font-size:24px;letter-spacing:-.04em;font-weight:500;line-height:1.2}
.logo svg{width:28px;height:28px}
.site-nav{display:flex;align-items:center;gap:28px;font-size:14px}
.language-link{color:var(--muted);transition:color .2s}
.language-link:hover{color:var(--text)}
.button{min-height:48px;padding:12px 24px;border-radius:999px;display:inline-flex;justify-content:center;align-items:center;gap:22px;font-size:14px;font-weight:550;line-height:1.4;transition:background .2s,border-color .2s,transform .2s}
.button span[aria-hidden]{font-size:21px;line-height:1;transition:transform .25s var(--ease)}
.button:hover span[aria-hidden],.text-link:hover span{transform:translate(2px,-2px)}
.button:active{transform:scale(.98)}
.button-outline{border:1px solid #73756f}
.button-outline:hover{background:#20221e;border-color:var(--text)}
.button-primary{background:var(--text);color:var(--bg);border:1px solid var(--text)}
.button-primary:hover{background:#d9dcd4;border-color:#d9dcd4}
.text-link{display:inline-flex;align-items:center;gap:14px;padding:10px 0;border-bottom:1px solid var(--muted);font-size:14px}
.text-link span{font-size:22px;transition:transform .25s var(--ease)}
.hero{min-height:614px;display:grid;grid-template-columns:1fr 1fr;align-items:center;gap:12px;padding-block:45px 68px;position:relative}
.hero-copy{position:relative;z-index:2}
h1{font-size:clamp(60px,6.5vw,98px);line-height:1.2;letter-spacing:-.075em;margin:0 0 34px;text-wrap:balance}
.hero-lede{color:var(--text);font-size:clamp(22px,2.4vw,34px);font-weight:500;letter-spacing:-.04em;line-height:1.5;margin-bottom:15px}
.hero-intro{max-width:35ch;font-size:16px;line-height:1.9}
.hero-actions{display:flex;align-items:center;gap:30px;margin-top:30px;flex-wrap:wrap}
.orbit-scene{position:relative;min-width:0;aspect-ratio:1.35;isolation:isolate}
.galaxy-canvas{position:absolute;inset:0;width:100%;height:100%;z-index:0;pointer-events:none;opacity:.7}
.galaxy-trigger{position:absolute;inset:5% 0 11%;z-index:2;border-radius:50%;padding:0;background:transparent}
.galaxy-trigger:focus-visible{outline:1px solid var(--text);outline-offset:5px}
.galaxy-trigger:disabled{cursor:default}
.orbit-map{position:relative;width:100%;height:100%;z-index:1;pointer-events:none;overflow:visible}
.orbit-line{fill:none;stroke:#777a70;stroke-width:.7;vector-effect:non-scaling-stroke}
.orbit-secondary{stroke:#55584e;stroke-dasharray:3 5;animation:orbit-breathe 12s ease-in-out infinite alternate}
.orbit-connection{stroke:#606459;stroke-width:.8;stroke-dasharray:3 5}
.orbit-bead{fill:var(--bg);stroke:var(--text);stroke-width:1}
.orbit-device{fill:var(--bg);stroke:var(--text);stroke-width:1.15}
.orbit-device path{fill:none}
.orbit-map text{fill:var(--muted);font:13px var(--font)}
.orbit-star{fill:var(--text);transform-origin:300px 232px;animation:star-breathe 4s ease-in-out infinite alternate}
.motion-toggle{position:absolute;bottom:10px;right:18px;z-index:3;display:flex;align-items:center;gap:8px;color:var(--muted);font-size:11px;min-height:40px;padding:8px 0}
.motion-toggle:hover{color:var(--text)}
.motion-toggle [data-motion-icon]{font-size:14px;width:16px}
[data-motion-paused=true] .orbit-secondary,[data-motion-paused=true] .orbit-star{animation-play-state:paused}
.chapter-nav{position:sticky;top:0;background:rgba(16,17,16,.97);z-index:10;border-block:1px solid var(--line)}
.chapter-inner{display:flex;align-items:stretch;gap:42px;min-height:76px}
.chapter-inner a{position:relative;display:flex;align-items:center;gap:12px;color:var(--muted);font-size:14px;white-space:nowrap;transition:color .2s}
.chapter-inner a::after{content:'';position:absolute;bottom:0;left:0;right:0;height:2px;background:var(--text);transform:scaleX(0);transform-origin:left;transition:transform .3s var(--ease)}
.chapter-inner a:hover,.chapter-inner a[aria-current=true]{color:var(--text)}
.chapter-inner a[aria-current=true]::after{transform:scaleX(1)}
.story{display:grid;grid-template-columns:1.15fr 1fr;gap:12%;align-items:center;padding-block:96px 106px}
.story h2{font-size:clamp(34px,4.5vw,60px);line-height:1.5;letter-spacing:-.055em}
.story p{font-size:17px;line-height:2;max-width:45ch}
.section{border-top:1px solid var(--line);padding-block:90px 96px;scroll-margin-top:12px}
.section-heading{display:grid;grid-template-columns:1.05fr 1fr;gap:10%;align-items:center;margin-bottom:48px}
.section-heading p{max-width:48ch}
.walkthrough{display:grid;grid-template-columns:.9fr 1.45fr;gap:7%}
.walkthrough h2{font-size:clamp(29px,3vw,43px)}
.section-subtitle{font-size:22px;line-height:1.5;color:var(--text);margin-top:10px;letter-spacing:-.035em}
.demo-disclaimer{font-size:13px;margin-top:12px}
.step-list{list-style:none;padding:0;margin-top:36px}
.step-list li{position:relative}
.step-list li:not(:last-child)::before{content:'';position:absolute;left:23px;top:47px;bottom:-4px;width:1px;background:var(--line)}
.step-link{position:relative;display:flex;align-items:center;gap:18px;padding:12px 0;color:var(--muted);font-size:18px}
.step-number{display:grid;place-items:center;border:1px solid #60635a;min-width:47px;height:47px;border-radius:50%;font:13px var(--mono);background:var(--bg);transition:border-color .2s,background .2s,color .2s}
.step-link:hover,.step-link[aria-selected=true]{color:var(--text)}
.step-link[aria-selected=true] .step-number{border-color:var(--text);background:var(--text);color:var(--bg)}
.demo-stage{border:1px solid #65685e;padding:29px 32px 26px;border-radius:3px;min-width:0;display:flex;flex-direction:column;align-self:start}
.demo-panel{display:flex;flex-direction:column;min-height:398px}
.demo-panel+.demo-panel{margin-top:35px;padding-top:35px;border-top:1px solid var(--line)}
.is-enhanced .demo-panel+.demo-panel{margin-top:0;padding-top:0;border-top:0}
.demo-panel-top .mono{color:var(--muted)}
.demo-panel-top h3{font-size:25px;margin-top:6px}
.demo-visual{display:flex;flex:1;min-height:230px;flex-direction:column;align-items:center;justify-content:center;padding:24px 0;gap:15px}
.demo-devices{display:flex;align-items:center;justify-content:space-between;width:100%;gap:10px;max-width:460px}
.demo-device{width:43%;display:flex;flex-direction:column;align-items:center;gap:12px}
.demo-device svg{width:100%;height:120px;stroke:#c9cdc0;stroke-width:1}
.demo-device span{font-size:12px;color:var(--muted)}
.demo-device.phone{width:30%}
.connection-mark{display:flex;align-items:center;justify-content:center;position:relative;flex:1;transform:translateY(-16px)}
.connection-mark::before{content:'';position:absolute;inset:50% -25px auto;border-top:1px dashed #63665b;z-index:-1}
.connection-mark svg{width:27px;height:27px;background:var(--bg)}
.demo-description{font-size:14px;line-height:1.9;max-width:55ch;margin-top:auto}
.demo-controls{display:flex;align-items:center;justify-content:space-between;gap:14px;margin-top:25px}
.demo-controls .button{padding:11px 21px}
.text-button{display:inline-flex;align-items:center;justify-content:center;gap:10px;padding:10px 0;font-size:13px;min-height:44px;color:var(--muted)}
.text-button:hover{color:var(--text)}
.text-button:disabled{opacity:.35}
.demo-action{color:var(--text);border-bottom:1px solid var(--line)}
.demo-room{display:flex;align-items:center;gap:15px;font-size:12px;color:var(--muted)}
.demo-room strong{letter-spacing:.24em;font:17px var(--mono);color:var(--text)}
.demo-panel[data-connected=true] .connection-mark::before{border-top-style:solid;border-color:var(--text)}
.sample-file{display:flex;align-items:center;gap:17px;padding:20px;width:100%;border:1px solid #595d50;border-radius:3px;text-align:left;transition:background .2s,border-color .2s}
.sample-file:hover,.sample-file[aria-pressed=true]{background:#1b1d19;border-color:var(--text)}
.sample-file strong{display:block;font:14px/1.5 var(--mono);overflow-wrap:anywhere}
.sample-file small{display:block;color:var(--muted);font-size:12px;margin-top:5px}
.file-symbol{font-size:24px}
.file-check{font-size:23px;margin-left:auto}
.sample-description{font-size:12px}
.verification-mark svg{width:56px;height:56px}
.demo-result{font-size:13px;line-height:1.8;max-width:43ch;text-align:center;overflow-wrap:anywhere}
.demo-result strong{display:block;font-size:17px;font-weight:500;color:var(--text);margin-bottom:7px}
.demo-result code{display:block;font-family:var(--mono);font-size:10px;letter-spacing:.01em;margin-top:10px}
.feature-row{display:grid;grid-template-columns:60px 1fr 1.1fr;gap:32px;align-items:baseline;padding:30px 0;border-top:1px solid var(--soft-line)}
.feature-number{color:var(--muted)}
.feature-row p{max-width:52ch;font-size:15px;line-height:1.9}
.privacy-layout,.spec-layout{display:grid;grid-template-columns:1fr 1.2fr;gap:10%}
.privacy-layout h2{font-size:clamp(36px,4vw,56px)}
.privacy-copy h3{font-size:23px;margin-bottom:25px;line-height:1.6}
.privacy-copy p+p{margin-top:18px}
.spec-layout{margin-top:64px;padding-top:38px;border-top:1px solid var(--soft-line)}
.spec-layout>h3{font-size:18px}
.spec-list>div{display:grid;grid-template-columns:150px 1fr;gap:24px;padding:15px 0;border-bottom:1px solid var(--soft-line);font-size:14px}
.spec-list dt{color:var(--muted)}
.spec-list dd{margin:0}
.limitation{font-size:13px;line-height:1.95;margin-top:24px}
.table-scroll{overflow-x:auto}
table{width:100%;border-collapse:collapse;text-align:left;font-size:14px;min-width:560px}
th,td{padding:20px 16px;border-bottom:1px solid var(--line);vertical-align:top}
th:first-child,td:first-child{padding-left:0}
th:last-child,td:last-child{padding-right:0}
thead th{font-size:12px;color:var(--muted);font-weight:400}
tbody th{font-weight:500;width:22%}
tbody td{color:var(--muted);width:39%}
.faq-section{display:grid;grid-template-columns:1fr 1.4fr;gap:8%}
.faq-heading p{margin-top:20px;font-size:16px}
.faq-item{border-top:1px solid var(--line)}
.faq-item:last-child{border-bottom:1px solid var(--line)}
.faq-item summary{list-style:none;cursor:pointer;display:flex;align-items:center;justify-content:space-between;gap:24px;font-size:18px;font-weight:400;line-height:1.6;padding:20px 0}
.faq-item summary::-webkit-details-marker{display:none}
.faq-toggle{position:relative;flex:0 0 16px;height:16px;margin-right:2px}
.faq-toggle::before,.faq-toggle::after{content:'';background:var(--text);position:absolute;top:7px;left:0;width:16px;height:1px}
.faq-toggle::after{transform:rotate(90deg);transition:transform .2s}
.faq-item[open] .faq-toggle::after{transform:rotate(0)}
.faq-item p{font-size:15px;line-height:1.95;padding:0 28px 24px 0}
.closing{text-align:center;border-top:1px solid var(--line);padding-block:85px 95px}
.closing>svg{width:34px;height:34px;margin:0 auto 32px}
.closing h2{font-size:clamp(35px,5vw,68px);line-height:1.4}
.closing p{margin:24px auto 30px;max-width:50ch;font-size:15px}
.site-footer{border-top:1px solid var(--line);padding-block:32px;display:flex;align-items:center;gap:25px;color:var(--muted);font-size:12px}
.site-footer .logo{font-size:19px;color:var(--text)}
.site-footer .logo svg{width:20px;height:20px}
.site-footer p{margin-right:auto}
.site-footer a:last-child{white-space:nowrap}
:lang(en) h1{font-size:clamp(53px,6.2vw,89px);letter-spacing:-.065em;line-height:1.14}
:lang(en) .hero-intro{max-width:37ch}
:lang(en) .story h2{font-size:clamp(33px,3.8vw,54px);line-height:1.25}
:lang(en) h2{letter-spacing:-.045em;line-height:1.2}
:lang(en) .feature-row h3{letter-spacing:-.025em}
@keyframes orbit-breathe{from{opacity:.5}to{opacity:1}}
@keyframes star-breathe{from{transform:scale(.93)}to{transform:scale(1.07)}}
@media(min-width:1500px){.hero{min-height:660px}}
@media(max-width:1100px){.shell{width:calc(100% - 72px)}.hero{min-height:570px}.hero-actions{gap:19px}.button{gap:15px;padding-inline:20px}.chapter-inner{gap:32px}.story{gap:7%}.walkthrough{gap:5%}.demo-stage{padding:25px}.feature-row{grid-template-columns:35px 1fr 1.1fr;gap:20px}.spec-list>div{grid-template-columns:120px 1fr;gap:16px}.faq-section{gap:6%}}
@media(max-width:800px){html{scroll-padding-top:78px}.shell{width:calc(100% - 40px)}.site-header{height:88px}.site-nav{gap:16px}.logo{font-size:22px}.logo svg{width:25px;height:25px}.hero{grid-template-columns:1fr;gap:8px;padding-block:40px 22px;min-height:0}.hero-copy{max-width:580px}h1{font-size:clamp(57px,10vw,78px);margin-bottom:24px}.hero-lede{font-size:25px}.hero-intro{max-width:42ch}.hero-actions{margin-top:26px}.orbit-scene{width:min(540px,100%);margin:-5px auto 0;aspect-ratio:1.55}.orbit-map{max-height:330px}.motion-toggle{bottom:0;right:0}.chapter-inner{gap:25px;overflow-x:auto;min-height:63px;scrollbar-width:none}.chapter-inner::-webkit-scrollbar{display:none}.chapter-inner a{font-size:12px;gap:8px}.chapter-inner .mono{font-size:10px}.story{padding-block:65px;gap:8%;grid-template-columns:1fr 1fr}.story h2{font-size:34px}.story p{font-size:15px}.section{padding-block:64px}.section-heading{gap:7%}.walkthrough{grid-template-columns:1fr;gap:32px}.walkthrough-guide{display:grid;grid-template-columns:1fr 1fr;column-gap:24px}.walkthrough-guide h2,.walkthrough-guide>.section-subtitle,.walkthrough-guide>.demo-disclaimer{grid-column:1}.step-list{grid-column:2;grid-row:1 / 5;margin-top:0}.step-link{font-size:15px;padding:9px 0;gap:12px}.step-number{min-width:37px;height:37px;font-size:11px}.step-list li:not(:last-child)::before{left:18px;top:39px}.demo-stage{width:100%;padding:25px 30px}.demo-panel{min-height:330px}.demo-visual{min-height:200px}.demo-devices{max-width:400px}.feature-row{grid-template-columns:30px .85fr 1.15fr;gap:20px}.feature-row h3{font-size:20px}.feature-row p{font-size:14px}.privacy-layout,.spec-layout{gap:7%;grid-template-columns:.85fr 1.15fr}.privacy-copy h3{font-size:20px}.privacy-copy p{font-size:14px}.spec-list>div{grid-template-columns:1fr;gap:2px}.spec-list dt{font-size:12px}.faq-section{grid-template-columns:.85fr 1.15fr}.faq-item summary{font-size:16px}.site-footer{flex-wrap:wrap;column-gap:18px;row-gap:12px}.site-footer p{flex:1;min-width:140px}.site-footer>span{margin-right:auto}:lang(en) h1{font-size:clamp(54px,10vw,76px)}:lang(en) .story h2{font-size:34px}}
@media(max-width:540px){.site-header{height:78px}.site-nav{gap:14px;font-size:12px}.site-nav .button{min-height:40px;padding:9px 13px;font-size:12px;gap:10px}.site-nav .button span{font-size:18px}.logo{font-size:19px;gap:8px}.logo svg{width:22px;height:22px}.hero{padding-top:28px}.hero-lede{font-size:22px}.hero-intro{font-size:14px}.hero-actions{gap:22px}.hero-actions .button{font-size:13px;padding-inline:18px}.text-link{font-size:13px}.orbit-scene{margin-top:9px;aspect-ratio:1.35}.motion-toggle{font-size:10px;bottom:-2px}.chapter-inner{gap:25px}.story{grid-template-columns:1fr;gap:24px;padding-block:55px}.story h2{font-size:35px}.story p{font-size:15px;max-width:42ch}.section{padding-block:54px}.section-heading{grid-template-columns:1fr;gap:20px;margin-bottom:30px}.section-heading h2{font-size:31px}.section-heading p{font-size:14px}.walkthrough-guide{display:block}.walkthrough h2{font-size:31px}.section-subtitle{font-size:20px}.step-list{display:grid;grid-template-columns:repeat(4,1fr);gap:6px;margin-top:28px}.step-list li:not(:last-child)::before{left:30px;right:-10px;top:26px;height:1px;width:auto;bottom:auto}.step-link{flex-direction:column;gap:12px;font-size:11px;line-height:1.6;align-items:flex-start;padding-block:8px}.step-number{min-width:37px;position:relative}.demo-stage{padding:22px 20px}.demo-panel{min-height:355px}.demo-panel-top h3{font-size:23px}.demo-description{font-size:13px}.demo-device svg{height:96px}.demo-device span{font-size:10px}.demo-visual{min-height:215px}.demo-controls{gap:8px}.demo-controls .button{font-size:12px;gap:12px;padding:10px 17px}.text-button{font-size:12px}.feature-row{grid-template-columns:26px 1fr;gap:10px 15px;padding-block:24px}.feature-row p{grid-column:2}.feature-row h3{font-size:21px}.privacy-layout,.spec-layout{grid-template-columns:1fr;gap:28px}.privacy-layout h2{font-size:38px}.privacy-copy h3{font-size:21px}.spec-layout{margin-top:42px;padding-top:28px}.spec-list>div{grid-template-columns:116px 1fr;gap:12px}.spec-list dt{font-size:12px}.spec-list dd{font-size:13px}.faq-section{grid-template-columns:1fr;gap:32px}.faq-heading h2{font-size:37px}.faq-heading p{margin-top:15px;font-size:14px}.faq-item summary{font-size:17px}.faq-item p{padding-right:12px}.closing{padding-block:64px}.closing h2{font-size:39px}.closing p{font-size:14px}.site-footer{padding-block:27px}.site-footer .logo{font-size:17px}.site-footer p{font-size:11px}.site-footer>span{font-size:10px}:lang(en) .step-link{font-size:10px;max-width:82px}:lang(en) .hero-actions{gap:18px}:lang(en) .hero-actions .button{font-size:12px;padding-inline:17px}:lang(en) .hero-actions .text-link{font-size:12px}:lang(en) .hero-actions .text-link span{font-size:18px}:lang(en) .closing h2{font-size:40px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*::before,*::after{animation:none!important;transition:none!important}.galaxy-canvas{opacity:.4}}

/* Keep every chapter visible on phones; the numbers retain the reading rhythm. */
@media(max-width:540px){
  .chapter-inner{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:12px;overflow:visible;min-height:76px}
  .chapter-inner a{min-width:0;flex-direction:column;align-items:flex-start;justify-content:center;gap:5px;padding-block:11px;white-space:normal;font-size:11px;line-height:1.4}
  .chapter-inner .mono{font-size:10px}
  :lang(en) .chapter-inner a{font-size:10px}
  /* 英文標籤會折成兩行、中文不會。給標籤一個兩行高的格子，
     四個序號才對得齊；超長時 minmax 仍可長高，不會裁字。 */
  :lang(en) .chapter-inner a{display:grid;grid-template-rows:auto minmax(2.8em,auto);align-content:center;justify-items:start}
}