/* 招小协（Apatie）介绍与下载页。令牌来自 website/design.md；招小协的页面更柔和活泼：圆角、衬线标题、滚动叙事。 */
@font-face{font-family:'Apatie Serif';src:url(/assets/fonts/apatie-serif-zh.woff2) format('woff2');font-weight:500 700;font-display:swap}
@font-face{font-family:'Instrument Serif';src:url(/assets/fonts/instrument-serif.woff2) format('woff2');font-weight:400;font-display:swap}
@font-face{font-family:'Instrument Serif';src:url(/assets/fonts/instrument-serif-italic.woff2) format('woff2');font-weight:400;font-style:italic;font-display:swap}

:root{
  color-scheme:light;
  --paper:#fff;--ink:#111318;--muted:#626b78;--on-accent:#fff;
  --line:color-mix(in srgb,var(--ink) 12%,transparent);
  --surface:color-mix(in srgb,var(--ink) 3.5%,var(--paper));
  --red:#b84f42;--red-soft:color-mix(in srgb,var(--red) 10%,var(--paper));--focus:#1f5aa8;
  --sans:'PingFang SC','PingFang TC','Hiragino Sans GB','Microsoft YaHei','Microsoft JhengHei','Noto Sans SC','Noto Sans TC',system-ui,-apple-system,'Segoe UI',sans-serif;
  --serif:'Instrument Serif','Apatie Serif','Songti SC','Songti TC','Noto Serif CJK SC','Source Han Serif SC',serif;
  --mono:ui-monospace,'SF Mono',Menlo,Consolas,monospace;
  --ease:cubic-bezier(.22,1,.36,1);--spring:cubic-bezier(.34,1.56,.64,1);
  --r-sm:8px;--r:12px;--r-lg:18px;
  --gutter:clamp(1rem,4vw,3rem);
  --shadow:0 1px 2px rgba(13,17,23,.05),0 12px 40px -12px rgba(13,17,23,.16);
}
:root[data-theme=dark]{
  color-scheme:dark;
  --paper:#0d1117;--ink:#f5f7fa;--muted:#a8b1be;--on-accent:#0d1117;--red:#d47c70;--focus:#87aae0;
  --line:color-mix(in srgb,var(--ink) 13%,transparent);
  --surface:color-mix(in srgb,var(--ink) 4.5%,var(--paper));
  --shadow:0 1px 2px rgba(0,0,0,.3),0 16px 48px -16px rgba(0,0,0,.6);
}
*,*::before,*::after{box-sizing:border-box}
html{scroll-behavior:smooth;scroll-padding-top:5rem}
body{margin:0;background:var(--paper);color:var(--ink);font:400 1rem/1.75 var(--sans);-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility;overflow-x:clip;transition:background-color 320ms var(--ease),color 320ms var(--ease)}
img,video{display:block;max-width:100%;height:auto}
a{color:inherit}
button{font:inherit;color:inherit}
:focus-visible{outline:2px solid var(--focus);outline-offset:3px;border-radius:6px}
.wrap{width:min(100% - 2*var(--gutter),72rem);margin-inline:auto}
.dk{display:none}
:root[data-theme=dark] .lt{display:none}
:root[data-theme=dark] .dk{display:block}

/* Header */
.top{position:sticky;top:0;z-index:20;background:var(--paper);border-bottom:1px solid transparent;transition:border-color 240ms}
.top.scrolled{border-bottom-color:var(--line)}
.bar{display:flex;align-items:center;justify-content:space-between;gap:1rem;height:4rem}
.brand{display:flex;align-items:center;gap:.5rem;line-height:1;text-decoration:none;font-weight:700;white-space:nowrap}
.brand img{border-radius:8px;flex:none}
.brand span{display:block;line-height:1}
.brand small{color:var(--muted);font:400 1.3125rem/1 'Instrument Serif',serif;letter-spacing:.005em}
.top nav{display:flex;align-items:center;gap:.375rem}
.navlink{padding:.375rem .625rem;border-radius:var(--r-sm);text-decoration:none;color:var(--muted);font-size:.9375rem;transition:color 160ms,background-color 160ms}
.navlink:hover{color:var(--ink);background:var(--surface)}
.seg{display:inline-flex;padding:3px;margin-left:.375rem;border-radius:10px;background:var(--surface);border:1px solid var(--line)}
.seg button{min-width:2rem;height:28px;padding:0 .5rem;border:0;border-radius:7px;background:none;color:var(--muted);font-size:.8125rem;font-weight:600;cursor:pointer;transition:background-color 200ms,color 200ms}
.seg button[aria-pressed=true]{background:var(--paper);color:var(--ink);box-shadow:0 1px 2px rgba(13,17,23,.14)}
.icon-btn{display:inline-grid;place-items:center;width:36px;height:36px;border:1px solid var(--line);border-radius:10px;background:none;cursor:pointer;transition:transform 200ms var(--spring),background-color 160ms}
.icon-btn:hover{background:var(--surface)}
.icon-btn:active{transform:scale(.9) rotate(-12deg)}
.icon-btn svg{width:20px;height:20px;display:block;overflow:visible}
/* Sun ↔ moon: the rays tuck away while a shadow slides across the disc. */
.ti-rays{fill:none;stroke:currentColor;stroke-width:1.8;stroke-linecap:round;transform-origin:12px 12px;transition:transform 520ms var(--spring),opacity 260ms}
.ti-core{transform-origin:12px 12px;transition:transform 520ms var(--spring)}
.ti-cut{transition:transform 520ms var(--ease)}
:root[data-theme=dark] .ti-rays{opacity:0;transform:rotate(-90deg) scale(.4)}
:root[data-theme=dark] .ti-core{transform:scale(1.55)}
:root[data-theme=dark] .ti-cut{transform:translate(-8px,5px)}
.icon-btn:hover .ti-rays{transform:rotate(30deg)}
:root[data-theme=dark] .icon-btn:hover .ti-core{transform:scale(1.55) rotate(-14deg)}
/* Theme change: a circle of the new theme grows from the button. */
::view-transition-old(root),::view-transition-new(root){animation:none;mix-blend-mode:normal}
.vt-theme::view-transition-old(root){z-index:1}
.vt-theme::view-transition-new(root){z-index:2}
.vt-theme body{transition:none}
.theming,.theming *,.theming *::before,.theming *::after{transition:background-color 420ms var(--ease),color 420ms var(--ease),border-color 420ms var(--ease),fill 420ms,stroke 420ms!important}

/* Buttons */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:.5rem;min-height:38px;padding:0 1.125rem;border-radius:var(--r);background:var(--ink);color:var(--paper);font-weight:600;font-size:.9375rem;text-decoration:none;white-space:nowrap;transition:transform 220ms var(--spring),box-shadow 220ms var(--ease),background-color 200ms}
.btn:hover{transform:translateY(-1px);box-shadow:0 8px 20px -8px color-mix(in srgb,var(--ink) 60%,transparent)}
.btn:active{transform:scale(.97)}
.btn-sm{min-height:34px;padding:0 .875rem;font-size:.875rem;border-radius:10px;margin-left:.25rem}
.btn-lg{min-height:48px;padding:0 1.5rem;font-size:1rem;border-radius:14px}
.dl-ico{width:18px;height:18px;fill:none;stroke:currentColor;stroke-width:2;stroke-linecap:round;stroke-linejoin:round}
.btn-lg:hover .dl-ico{animation:nudge 700ms var(--ease)}
@keyframes nudge{40%{transform:translateY(3px)}}
.link{color:var(--muted);text-underline-offset:4px;font-size:.9375rem}.link:hover{color:var(--ink)}

/* Type */
.display{font-family:var(--serif);font-weight:600;letter-spacing:-.01em;line-height:1.12;text-wrap:balance;margin:0}
.display em{font-style:italic;color:var(--red)}
:root:not([data-lang=en]) .display em{font-style:normal}
:root[data-lang=en] .display{font-weight:400;letter-spacing:-.015em;line-height:1.02}
h1.display{font-size:clamp(2.75rem,8vw,6.25rem)}
:root[data-lang=en] h1.display{font-size:clamp(3.25rem,9.5vw,7.5rem)}
h2.display{font-size:clamp(2rem,4.8vw,3.5rem)}
:root[data-lang=en] h2.display{font-size:clamp(2.375rem,5.6vw,4.25rem)}
h3.display{font-size:1.5rem}
:root[data-lang=en] h3.display{font-size:1.875rem}
.eyebrow{display:inline-block;margin:0 0 1rem;padding:.25rem .625rem;border-radius:999px;background:var(--red-soft);color:var(--red);font-size:.8125rem;font-weight:600;letter-spacing:.02em}
.lede{margin:1.25rem 0 0;max-width:38rem;font-size:clamp(1.0625rem,1.5vw,1.1875rem);color:var(--muted);text-wrap:pretty}

/* Hero */
.hero{position:relative;padding:clamp(3rem,8vw,6rem) 0 0;text-align:center}
.hero-in{position:relative;z-index:1}
.hero .lede{margin-inline:auto}
.hero h1 .ln{display:block;overflow:hidden;padding-bottom:.08em}
.hero h1 .ln>span{display:inline-block}
.cta{display:flex;gap:1.25rem;align-items:center;justify-content:center;flex-wrap:wrap;margin-top:2rem}
.meta{margin:1rem 0 0;color:var(--muted);font-size:.875rem;font-variant-numeric:tabular-nums}
.hero-shot{margin-top:clamp(2.5rem,6vw,4.5rem);transform-origin:50% 0;will-change:transform}
.stickers{position:absolute;inset:0;pointer-events:none;overflow:hidden}
.st{position:absolute;color:var(--red);opacity:.55;font-weight:600;white-space:nowrap;animation:bob 6s ease-in-out infinite;translate:calc(var(--mx,0) * var(--d,10px)) calc(var(--my,0) * var(--d,10px));transition:translate 600ms var(--ease)}
.st1{--d:-18px}.st2{--d:12px}.st3{--d:-10px}.st4{--d:22px}.st5{--d:8px}
.st1{left:9%;top:16%;font-size:1.75rem}
.st2{right:8%;top:22%;font-size:1rem;animation-delay:-2s}
.st3{left:14%;top:46%;font-size:1.5rem;animation-delay:-4s}
.st4{right:15%;top:52%;font-size:1.25rem;animation-delay:-1s}
.st5{left:4%;top:31%;font-size:.9375rem;animation-delay:-3s}
@keyframes bob{50%{transform:translateY(-10px) rotate(4deg)}}

/* Frames */
.frame{margin:0;position:relative;overflow:hidden;border:1px solid var(--line);border-radius:var(--r-lg);background:var(--paper);box-shadow:var(--shadow)}
.frame img,.frame video{width:100%}
.chrome{display:flex;align-items:center;gap:.4rem;height:2.25rem;padding:0 .875rem;border-bottom:1px solid var(--line);background:var(--surface)}
.chrome i{width:.625rem;height:.625rem;border-radius:50%;background:var(--line)}
.chrome i:nth-child(1){background:#ff5f57}.chrome i:nth-child(2){background:#febc2e}.chrome i:nth-child(3){background:#28c840}
.chrome span{margin:0 auto;transform:translateX(-1.1rem);font-size:.75rem;color:var(--muted)}

/* Sections */
.block{padding-top:clamp(5rem,12vw,9rem)}
.head{margin-bottom:clamp(1.5rem,3vw,2.25rem)}
.zoom{transform-origin:50% 30%;will-change:transform}

/* 招小协: a kaomoji face and a speech card. */
.guide{display:flex;align-items:flex-start;gap:.75rem;max-width:34rem;margin:0 0 2rem}
.hero-guide{justify-content:center;margin:0 auto 2rem;text-align:left}
/* Fixed size, so the rotating lines never nudge the layout. */
.hero-guide .bubble{width:min(25rem,100%)}
.hero-guide .bubble span{min-height:calc(2em * 1.65)}
@media (max-width:480px){
  .hero-guide{flex-direction:column;align-items:flex-start;gap:.5rem}
  .hero-guide .bubble{width:100%}
  :root[data-lang=en] .hero-guide .bubble span{min-height:calc(3em * 1.65)}
}
.face{flex:none;display:inline-flex;align-items:center;justify-content:center;height:44px;padding:0 .875rem;border:0;border-radius:14px;background:var(--red-soft);color:var(--red);font:600 1.125rem/1 var(--sans);white-space:pre;cursor:pointer;transform-origin:50% 90%;-webkit-tap-highlight-color:transparent;transition:transform 240ms var(--spring)}
.face:hover{transform:rotate(-4deg) scale(1.04)}
.face span{display:inline-block;text-align:center}
.face.sm{height:36px;padding:0 .75rem;font-size:.9375rem;border-radius:12px;cursor:default}
.bubble{position:relative;margin:0;padding:.625rem .875rem .7rem;border:1px solid var(--line);border-radius:14px;border-top-left-radius:4px;background:var(--paper);font-size:.9375rem;line-height:1.65;text-wrap:pretty;box-shadow:0 6px 20px -12px rgba(13,17,23,.25)}
.bubble b{display:block;margin-bottom:.125rem;color:var(--red);font-size:.75rem;font-weight:650;letter-spacing:.04em}
.bubble span{display:block;transition:opacity 160ms,transform 200ms var(--ease)}
.bubble span.swap{opacity:0;transform:translateY(4px)}
.face.hop{animation:g-hop 560ms var(--ease)}
.face.wave{animation:g-wave 1000ms var(--ease)}
.face.cheer{animation:g-hop 520ms var(--ease) 2}
@keyframes g-hop{0%,100%{transform:none}35%{transform:translateY(-8px) scale(1.04)}65%{transform:translateY(1px) scale(.98)}}
@keyframes g-wave{0%,100%{transform:none}20%{transform:rotate(-8deg)}45%{transform:rotate(7deg)}70%{transform:rotate(-3deg)}}
.mini{display:inline-block;margin-bottom:.75rem;color:var(--red);font-size:1.125rem;font-weight:600;white-space:pre;transition:transform 300ms var(--spring)}

/* Pinned story */
.story-grid{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,20rem);gap:clamp(2rem,5vw,4.5rem)}
.stage{position:sticky;top:calc(4rem + max(3vh,1.5rem));align-self:start}
.stage{width:min(100%,calc((100svh - 10.5rem) * 1.6));justify-self:center}
.shots{position:relative;aspect-ratio:1920/1200}
.shot{position:absolute;inset:0;opacity:0;transform:scale(1.03);transition:opacity 520ms var(--ease),transform 700ms var(--ease)}
.shot.on{opacity:1;transform:none}
.shot img{width:100%;height:100%;object-fit:cover}
.progress{display:flex;gap:6px;justify-content:center;margin-top:1rem}
.progress i{width:6px;height:6px;border-radius:3px;background:var(--line);transition:width 360ms var(--ease),background-color 300ms}
.progress i.on{width:22px;background:var(--red)}
.stage-guide{position:absolute;right:-.75rem;bottom:2.25rem}
.stage-guide .face{box-shadow:var(--shadow);background:var(--paper);border:1px solid var(--line)}
.steps{padding:16vh 0 14vh}
.step{min-height:62vh;display:flex;flex-direction:column;justify-content:center;opacity:.28;transform:translateX(8px);transition:opacity 420ms var(--ease),transform 420ms var(--ease)}
.step.on{opacity:1;transform:none}
.step-no{margin:0 0 .5rem;font:italic 400 1.5rem/1 'Instrument Serif',serif;color:var(--red)}
.step p:last-child{margin:.75rem 0 0;color:var(--muted)}

/* Features */
.three{display:grid;grid-template-columns:repeat(3,1fr);gap:1rem}
.card{position:relative;overflow:hidden;padding:1.75rem 1.5rem 1.5rem;border:1px solid var(--line);border-radius:var(--r-lg);background:var(--surface);transition:translate 320ms var(--spring),box-shadow 320ms var(--ease),opacity 800ms var(--ease),transform 900ms var(--ease)}
.card::before{content:'';position:absolute;inset:0;border-radius:inherit;pointer-events:none;opacity:0;background:radial-gradient(22rem circle at var(--x,50%) var(--y,0%),color-mix(in srgb,var(--red) 10%,transparent),transparent 60%);transition:opacity 300ms}
.card>*{position:relative}
.card:hover{translate:0 -4px;box-shadow:var(--shadow)}
.card:hover::before{opacity:1}
.card:hover .mini{transform:rotate(-8deg) scale(1.08)}
.card p{margin:.625rem 0 0;color:var(--muted)}

/* Sign-in */
.split{display:grid;grid-template-columns:minmax(0,5fr) minmax(0,7fr);gap:clamp(2rem,5vw,4.5rem);align-items:center}
.plain{margin:1.5rem 0 2rem;padding:0;list-style:none;display:grid;gap:.625rem}
.plain li{padding-left:1.375rem;position:relative;color:var(--muted);text-wrap:pretty}
.plain li::before{content:'';position:absolute;left:0;top:.62em;width:8px;height:8px;border-radius:50%;background:var(--red)}
.pair{position:relative;display:grid;grid-template-columns:minmax(0,1fr) minmax(0,.36fr);gap:1rem;align-items:end}
.phone{margin:0;overflow:hidden;border:1px solid var(--line);border-radius:24px;background:var(--paper);box-shadow:var(--shadow)}
.match{position:absolute;left:50%;top:-1.25rem;display:flex;align-items:center;gap:.5rem;padding:.375rem .875rem;border-radius:999px;background:var(--ink);color:var(--paper);font:600 1rem/1 var(--sans);font-variant-numeric:tabular-nums;box-shadow:var(--shadow);transform:translateX(-50%)}
.match i{font-style:normal;color:var(--red);opacity:0;transform:scale(.4);transition:opacity 300ms 500ms,transform 400ms var(--spring) 500ms}
.match span{transition:transform 600ms var(--spring)}
.match span:first-child{transform:translateX(-14px)}
.match span:last-child{transform:translateX(14px)}
.match.in span{transform:none}
.match.in i{opacity:1;transform:none}
.code{position:absolute;left:1.75rem;bottom:-1.5rem;padding:.5rem .875rem;border:1px solid var(--line);border-radius:12px;background:var(--paper);box-shadow:var(--shadow);font:600 .9375rem/1 var(--mono);letter-spacing:.14em;white-space:pre}
.code small{display:block;margin-bottom:.375rem;font:600 .625rem/1 var(--sans);letter-spacing:.06em;color:var(--red)}
.code b{font-weight:inherit;color:var(--muted)}
.burst{position:fixed;z-index:60;left:0;top:0;pointer-events:none;color:var(--red);font-weight:600;white-space:pre}

/* Downloads */
.dl{display:grid;gap:.625rem}
.row{display:grid;grid-template-columns:1fr auto auto;gap:1.25rem;align-items:center;padding:1rem 1rem 1rem 1.25rem;border:1px solid var(--line);border-radius:var(--r);background:var(--paper);transition:border-color 200ms,transform 260ms var(--spring)}
.row:hover{border-color:color-mix(in srgb,var(--ink) 30%,transparent);transform:translateX(2px)}
.row[data-detected=true]{border-color:var(--red);background:var(--red-soft)}
.row b{font-weight:650}
.row small{display:block;color:var(--muted);font-size:.875rem;line-height:1.5}
.row .size{color:var(--muted);font:.8125rem var(--mono)}
.badge{margin-left:.5rem;padding:.125rem .5rem;border-radius:999px;background:var(--red);color:var(--on-accent);font-size:.6875rem;font-weight:650;vertical-align:2px}
.empty{display:flex;align-items:center;gap:.75rem;padding:1.25rem;border:1px dashed var(--line);border-radius:var(--r);color:var(--muted)}
.empty .mini{margin:0}
.foot-note{margin:1.25rem 0 0;color:var(--muted);font-size:.875rem}

.foot{margin-top:clamp(5rem,12vw,9rem);padding:2rem 0;border-top:1px solid var(--line);color:var(--muted);font-size:.875rem}
.foot .wrap{display:flex;justify-content:space-between;gap:1rem;flex-wrap:wrap}

[hidden]{display:none!important}

/* Opening sequence (once, on load) */
.js .intro,.js .hero-shot,.js .top{opacity:0}
.js .hero h1 .ln>span{transform:translateY(105%)}
.ready .top{opacity:1;transition:opacity 600ms var(--ease)}
.ready .hero-guide{animation:pop 700ms var(--spring) 120ms both}
.ready .hero h1 .ln>span{transform:none;transition:transform 900ms var(--ease)}
.ready .hero h1 .ln:nth-child(1)>span{transition-delay:220ms}
.ready .hero h1 .ln:nth-child(2)>span{transition-delay:320ms}
.ready .lede.intro,.ready .cta.intro,.ready .meta.intro{animation:rise 800ms var(--ease) both}
.ready .lede.intro{animation-delay:480ms}.ready .cta.intro{animation-delay:580ms}.ready .meta.intro{animation-delay:660ms}
.ready .hero-shot{opacity:1;transition:opacity 900ms var(--ease) 600ms}
.ready .st{animation:stin 900ms var(--spring) both,bob 6s ease-in-out 900ms infinite}
.ready .st2{animation-delay:700ms,-2s}.ready .st3{animation-delay:800ms,-4s}.ready .st4{animation-delay:900ms,-1s}.ready .st5{animation-delay:1000ms,-3s}.ready .st1{animation-delay:600ms,0s}
@keyframes pop{from{opacity:0;transform:scale(.6) translateY(12px)}to{opacity:1;transform:none}}
@keyframes rise{from{opacity:0;transform:translateY(18px)}to{opacity:1;transform:none}}
@keyframes stin{from{opacity:0;transform:scale(.3)}to{opacity:.55;transform:none}}

/* Reveal on scroll */
.js .rv{opacity:0;transform:translateY(28px)}
.js .rv.in{opacity:1;transform:none;transition:opacity 800ms var(--ease),transform 900ms var(--ease)}
.js .card.rv.in{transition:translate 320ms var(--spring),box-shadow 320ms var(--ease),opacity 800ms var(--ease),transform 900ms var(--ease)}
.three .rv.in:nth-child(2){transition-delay:0ms,0ms,90ms,90ms}.three .rv.in:nth-child(3){transition-delay:0ms,0ms,180ms,180ms}

@media(max-width:900px){
  .navlink{display:none}
  .three{grid-template-columns:1fr}
  .split{grid-template-columns:1fr}
  .story-grid{grid-template-columns:1fr;gap:0}
  .stage{top:4.5rem;z-index:2;background:var(--paper);padding:.5rem 0 .25rem}
  .stage{width:auto;justify-self:stretch}
  .stage>.frame{width:min(100%,calc((52svh - 2.25rem) * 1.6));margin-inline:auto}
  .stage-guide{display:none}
  .steps{padding:4vh 0 10vh}
  .step{min-height:max(36svh,11rem)}
  .st2,.st4{display:none}
}
@media(max-width:560px){
  .brand small{display:none}
  .btn-sm{display:none}
  .seg button{min-width:1.75rem;padding:0 .375rem}
  .pair{grid-template-columns:1fr}.phone{max-width:15rem;margin-inline:auto}
  .code{display:none}
  .row{grid-template-columns:1fr auto}.row .size{display:none}
  .chrome span{display:none}
  .face{font-size:1rem;padding:0 .625rem}
  .hero-guide{justify-content:flex-start}
  .st1,.st3,.st5{display:none}
}
@media(max-height:520px){
  .stage{position:relative;top:auto!important}
  .step{opacity:1;transform:none;min-height:0;padding:2rem 0}
  .steps{padding:1rem 0 0}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{animation:none!important;transition:none!important}
  .js .intro,.js .hero-shot,.js .top,.js .rv{opacity:1;transform:none}
  .js .hero h1 .ln>span{transform:none}
  .st{opacity:.55}
  .step{opacity:1;transform:none}
  .hero-shot,.zoom{transform:none!important}
}