/* 配色取自 assets/hero-notebook.jpg：砖红 #ac3d23、石板蓝 #4e6d83、橄榄 #6d7440、沙金 #b58c4e，墨色是暖褐不是黑 */
@font-face{font-family:WenKai;src:url("assets/fonts/wenkai-regular.woff2") format("woff2");font-weight:400;font-display:swap}
@font-face{font-family:WenKai;src:url("assets/fonts/wenkai-medium.woff2") format("woff2");font-weight:500;font-display:swap}

:root{
  --paper:#f1e8d8;--sheet:#fbf5e9;--sheet-2:#ebe1cd;
  --ink:#3a332b;--soft:#585144;--muted:#7c7466;--rule:#ddd1ba;
  --slate:#4e6d83;--clay:#ac3d23;--moss:#6d7440;--ochre:#a9803c;
  --deep:#2b3742;
  --kai:WenKai,'LXGW WenKai','Kaiti SC','STKaiti','KaiTi','Songti SC','Noto Serif SC',serif;
  --wrapw:1140px;--gutter:clamp(18px,4vw,40px)
}
*{box-sizing:border-box}
html{scroll-behavior:smooth;scroll-padding-top:80px}
body{margin:0;background:var(--paper);color:var(--ink);font:400 16px/1.9 var(--kai);-webkit-font-smoothing:antialiased;
  background-image:url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.9' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' opacity='.05' filter='url(%23n)'/%3E%3C/svg%3E")}
a{color:inherit}
img{display:block;max-width:100%;height:auto}
button{font:inherit;color:inherit;background:none;border:0;padding:0;cursor:pointer}
:focus-visible{outline:2px solid var(--slate);outline-offset:4px;border-radius:4px}
h1,h2,h3,h4,p,ul,ol,dl,dd,figure{margin:0}
ul,ol{padding:0;list-style:none}

/* 语言切换：默认中文，data-lang=en 时显示英文 */
:root:not([data-lang=en]) .en,:root[data-lang=en] .zh{display:none!important}

.wrap{width:100%;max-width:calc(var(--wrapw) + 2*var(--gutter));margin-inline:auto;padding-inline:var(--gutter)}
.skip{position:absolute;left:-9999px}
.skip:focus{left:16px;top:16px;z-index:99;background:var(--sheet);padding:10px 14px}
.eyebrow{font-size:14px;color:var(--slate);letter-spacing:.02em}

/* ---------- header ---------- */
.top{position:sticky;top:env(safe-area-inset-top,0px);z-index:20;background:#f1e8d8e6;backdrop-filter:blur(10px);-webkit-backdrop-filter:blur(10px);border-bottom:1px solid #ddd1ba80}
.top-in{height:66px;display:flex;align-items:center;justify-content:space-between;gap:16px}
.brand{display:flex;align-items:center;gap:14px;text-decoration:none;white-space:nowrap}
.mono{font:italic 28px/1 Georgia,serif;color:var(--slate);letter-spacing:-.05em}
.brand-name{font-size:14px;letter-spacing:.04em}
.brand-name i{font-style:normal;color:#a99f8c;margin:0 8px}
.top nav{display:flex;align-items:center;gap:clamp(12px,2.4vw,26px);font-size:15px}
.top nav a{text-decoration:none;color:var(--soft)}
.top nav a:hover{color:var(--slate)}
#lang{font-size:13px;border:1px solid var(--rule);border-radius:99px;padding:3px 12px;background:var(--sheet)}
#lang:hover{border-color:var(--ink)}

/* ---------- hero ---------- */
.hero{display:grid;grid-template-columns:minmax(0,5fr) minmax(0,7fr);gap:clamp(24px,4vw,60px);align-items:center;padding-block:clamp(36px,6vw,84px) clamp(24px,4vw,44px)}
.hero h1{font:500 clamp(30px,3.5vw,47px)/1.55 var(--kai);margin:16px 0 22px}
.lede{font-size:clamp(15px,1.25vw,17px);color:var(--soft);max-width:29em;line-height:2}
.cta{display:flex;align-items:center;flex-wrap:wrap;gap:22px;margin-top:30px}
.btn{display:inline-flex;align-items:center;gap:14px;background:var(--slate);color:#fdf8ec;text-decoration:none;padding:12px 24px;border-radius:99px;font-size:15px;transition:transform .2s,background .2s}
.btn:hover{transform:translateY(-2px);background:#3f5c70}
.link{font-size:15px;text-decoration:underline;text-decoration-color:var(--slate);text-decoration-thickness:2px;text-underline-offset:6px}
.link:hover{color:var(--slate)}
.hero-art{position:relative}
.hero-art img{mix-blend-mode:multiply;width:100%}

/* ---------- stats ---------- */
.stats{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));margin-bottom:clamp(52px,7vw,104px)}
.stat{padding:20px 24px;border-top:1px solid var(--ink);display:flex;flex-direction:column;gap:2px}
.stat+.stat{border-left:1px solid var(--rule)}
.stat b{font:500 clamp(30px,3.4vw,44px)/1.15 var(--kai);color:var(--slate)}
.stat span{font-size:14.5px;color:var(--soft)}
.stat small{display:block;font-size:13px;color:var(--muted);margin-top:3px}

/* ---------- section heads ---------- */
.section-head{margin-bottom:clamp(28px,4vw,46px)}
.section-head h2{font:500 clamp(26px,3vw,38px)/1.6 var(--kai);margin-top:8px;max-width:22em}
.section-lede{color:var(--soft);margin-top:12px;max-width:34em}

/* ---------- 手账跨页 ---------- */
.spread{position:relative;display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);margin-bottom:clamp(44px,6vw,88px)}
.spread>.page{position:relative;box-shadow:0 18px 36px -24px #4a3b2159}
.page-art{border-radius:10px 0 0 10px;padding:clamp(26px,4vw,52px);display:flex;flex-direction:column;align-items:center;justify-content:center;background:linear-gradient(90deg,var(--sheet) 86%,#e7dcc6)}
.page-text{border-radius:0 10px 10px 0;padding:clamp(26px,4vw,52px);background:linear-gradient(90deg,#e7dcc6,var(--sheet) 12%)}
.spread.flip .page-art{order:2;border-radius:0 10px 10px 0;background:linear-gradient(270deg,var(--sheet) 86%,#e7dcc6)}
.spread.flip .page-text{order:1;border-radius:10px 0 0 10px;background:linear-gradient(270deg,#e7dcc6,var(--sheet) 12%)}
.spread::before{content:'';position:absolute;top:0;bottom:0;left:50%;width:2px;transform:translateX(-1px);background:#d5c9b1;z-index:1}

.photo{position:relative;width:min(100%,420px);background:#fffefb;padding:10px 10px 12px;box-shadow:0 1px 2px #4a3b211a,0 16px 30px -18px #4a3b2166;transform:rotate(-1.5deg)}
.spread.flip .photo{transform:rotate(1.5deg)}
.photo img{width:100%}
.photo.tall{width:min(100%,300px)}
.tape{position:absolute;top:-14px;left:50%;width:110px;height:28px;transform:translateX(-50%) rotate(-3deg);background:color-mix(in srgb,var(--accent) 30%,#fffbee 70%);opacity:.85}
.note{font-size:clamp(16px,1.5vw,19px);line-height:1.75;text-align:center;margin-top:16px;transform:rotate(-1.2deg);color:var(--accent);max-width:24em}

.collage{position:relative;width:min(108%,540px);padding:0 0 64px}
.photo.phone{position:absolute;right:-6%;bottom:0;width:34%;padding:6px;border-radius:14px;background:#2c2b28;transform:rotate(4deg);display:block}
.photo.phone img{border-radius:9px}

.page-text h3.project{display:flex;align-items:baseline;flex-wrap:wrap;gap:0 12px;font:500 clamp(22px,2.1vw,28px)/1.5 var(--kai);margin:0 0 10px}
.page-text h3.project b{display:inline-grid;place-items:center;align-self:center;min-width:34px;height:23px;padding:0 8px;border-radius:99px;background:var(--accent);color:#fffdf5;font-size:13px;font-weight:400;flex:none}
.meta{font-size:13.5px;color:var(--muted)}
.brief{margin-top:16px;color:var(--soft);font-size:15.5px}
.page-text h4{font-size:14px;color:var(--accent);margin:26px 0 6px}
.did li{display:grid;grid-template-columns:5.8em minmax(0,1fr);gap:4px 14px;font-size:15px;color:var(--soft);padding:10px 0;border-top:1px dashed var(--rule)}
:root[data-lang=en] .did li{grid-template-columns:7.6em minmax(0,1fr)}
.did li>b{color:var(--ink);font-weight:500;font-size:14.5px}
.flow{grid-column:2;display:flex;flex-wrap:wrap;gap:6px 4px;margin-top:8px}
.flow li{font-size:13px;padding:2px 10px;border-radius:99px;background:color-mix(in srgb,var(--accent) 11%,var(--sheet));color:var(--ink);display:flex;align-items:center}
.flow li+li::before{content:'→';color:var(--accent);margin:0 6px 0 -2px;font-size:12px}
.results{display:grid;grid-template-columns:repeat(auto-fit,minmax(102px,1fr));gap:10px;margin-top:22px}
.results div{background:color-mix(in srgb,var(--accent) 8%,var(--sheet));border-radius:8px;padding:12px 14px;display:flex;flex-direction:column}
.results b{font:500 25px/1.2 var(--kai);color:var(--accent)}
.results span{font-size:13px;color:var(--soft);margin-top:2px}
.outcome{font-size:15px;color:var(--soft);margin-top:22px;padding-left:16px;border-left:2px solid var(--rule)}
.visit{display:inline-flex;gap:6px;margin-top:20px;font-size:14.5px;text-decoration:none;border-bottom:1.5px solid var(--accent);padding-bottom:2px}
.visit+.visit{margin-left:22px}
.visit:hover{color:var(--accent)}

/* ---------- method ---------- */
.method{background:var(--sheet-2);border-block:1px solid var(--rule);padding-block:clamp(52px,7vw,92px)}
.steps{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:clamp(12px,2vw,22px)}
.steps li{background:var(--sheet);border-radius:10px;padding:20px 20px 22px;border-top:3px solid var(--c);box-shadow:0 12px 26px -22px #4a3b2166}
.steps b{font:500 13px/1 var(--kai);color:var(--c)}
.steps h3{font:500 21px/1.4 var(--kai);margin:8px 0 6px}
.steps p{font-size:14px;color:var(--soft);line-height:1.85}
.kit{display:grid;grid-template-columns:1fr 2fr;gap:24px;margin-top:clamp(26px,4vw,42px)}
.kit h3{font-size:14px;color:var(--muted);margin-bottom:8px}
.chips{display:flex;flex-wrap:wrap;gap:8px}
.chips li{font-size:13.5px;padding:4px 14px;border:1px solid var(--rule);background:var(--sheet);border-radius:99px}

/* ---------- timeline ---------- */
.timeline{padding-block:clamp(52px,7vw,92px)}
.tl li{display:grid;grid-template-columns:11em minmax(0,1fr);gap:16px;padding:18px 0;border-top:1px solid var(--rule);align-items:baseline}
.tl li:last-child{border-bottom:1px solid var(--rule)}
.tl time{font-size:14.5px;color:var(--muted);display:flex;align-items:center;gap:12px}
.tl time::before{content:'';width:9px;height:9px;border-radius:50%;background:var(--c);flex:none}
.tl h3{font:500 19px/1.5 var(--kai)}
.tl p{font-size:14px;color:var(--soft)}

/* ---------- contact ---------- */
.contact{background:var(--deep);color:#f2ebdc;padding-block:clamp(52px,7vw,92px)}
.contact .eyebrow{color:#a8bdcc}
.contact-in{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:clamp(28px,5vw,68px);align-items:center}
.contact h2{font:500 clamp(28px,3.6vw,46px)/1.5 var(--kai);margin:14px 0 22px}
.contact-lede{color:#bdb6a6;font-size:15px;max-width:26em;margin-bottom:24px}
.wechat{display:inline-flex;align-items:center;gap:14px;flex-wrap:wrap;background:#ffffff10;border:1px solid #ffffff2e;border-radius:12px;padding:13px 18px}
.wechat-label{font-size:13px;color:#a9a293}
.wechat b{font-size:clamp(18px,1.9vw,21px);font-weight:500}
.copy{font-size:13px;border:1px solid #ffffff45;border-radius:99px;padding:4px 13px;transition:background .25s,border-color .25s,color .25s}
.copy:hover{background:#ffffff22}
.copy.done{background:#e2c169;border-color:#e2c169;color:#2b3742}
.contact-art.qr{background:#fffefb;max-width:352px;padding:16px 16px 10px;justify-self:end;transform:rotate(1.5deg);box-shadow:0 26px 50px -28px #000}
.contact-art.qr img{width:100%}
.contact-art.qr figcaption{font-size:15px;text-align:right;color:var(--slate);margin-top:6px}
.foot{display:flex;justify-content:space-between;align-items:center;flex-wrap:wrap;gap:8px;padding-block:20px;font-size:13.5px;color:var(--muted)}

/* ================= motion ================= */
.top{transition:box-shadow .3s}
.top.scrolled{box-shadow:0 8px 24px -18px #4a3b2166}
.progress{position:absolute;left:0;bottom:-1px;height:2px;width:100%;background:var(--slate);transform-origin:0 50%;transform:scaleX(var(--p,0))}
.top nav a{position:relative}
.top nav a::after{content:'';position:absolute;left:0;right:0;bottom:-4px;height:1.5px;background:var(--slate);transform:scaleX(0);transform-origin:0 50%;transition:transform .35s cubic-bezier(.2,.8,.2,1)}
.top nav a:hover::after,.top nav a[aria-current=true]::after{transform:scaleX(1)}
.top nav a[aria-current=true]{color:var(--ink)}
.btn span[aria-hidden]{transition:transform .25s}
.btn:hover span[aria-hidden]{transform:translateY(3px)}
.visit span[aria-hidden]{display:inline-block;transition:transform .25s}
.visit:hover span[aria-hidden]{transform:translate(3px,-3px)}

.photo{transition:transform .5s cubic-bezier(.2,.8,.2,1),box-shadow .5s}
.photo:hover,.spread.flip .photo:hover{transform:rotate(0) translateY(-6px) scale(1.015);box-shadow:0 1px 2px #4a3b211a,0 28px 44px -22px #4a3b2180}
.photo:hover .tape{animation:wiggle .6s ease}
@keyframes wiggle{30%{transform:translateX(-50%) rotate(2deg)}65%{transform:translateX(-50%) rotate(-6deg)}}
.hero-art img{transition:transform .6s cubic-bezier(.2,.8,.2,1);transform:translate(var(--mx,0),var(--my,0))}
.contact-art.qr{transition:transform .5s cubic-bezier(.2,.8,.2,1)}
.contact-art.qr:hover{transform:rotate(0) translateY(-6px)}
.results div,.steps li,.chips li{transition:transform .3s cubic-bezier(.2,.8,.2,1),box-shadow .3s,background .3s}
.results div:hover{transform:translateY(-3px)}
.steps li:hover{transform:translateY(-5px);box-shadow:0 22px 34px -24px #4a3b2188}
.chips li:hover{transform:translateY(-2px);background:#fffdf6}
.tl li{transition:background .3s}
.tl li:hover{background:#fbf5e999}

/* 流程链：像流水线一样依次点亮，循环播放 */
.spread.in .flow li{animation:flow-run 5.6s ease-in-out infinite;animation-delay:calc(var(--i,0) * .5s + 1s)}
@keyframes flow-run{0%,14%,100%{background:color-mix(in srgb,var(--accent) 11%,var(--sheet));color:var(--ink)}5%,9%{background:var(--accent);color:#fffdf5}}

@media (prefers-reduced-motion:no-preference){
  .hero-text>*{animation:up .8s cubic-bezier(.2,.8,.2,1) both}
  .hero-text>:nth-child(2){animation-delay:.1s}
  .hero-text>:nth-child(3){animation-delay:.22s}
  .hero-text>:nth-child(4){animation-delay:.34s}
  .hero-art img{animation:pop 1.1s .15s cubic-bezier(.2,.9,.3,1.15) both}
  @keyframes up{from{opacity:0;transform:translateY(22px)}}
  @keyframes pop{from{opacity:0;scale:.92;rotate:-3deg}}

  .js .reveal{transition:opacity .8s cubic-bezier(.2,.8,.2,1),transform .8s cubic-bezier(.2,.8,.2,1)}
  .js .reveal:not(.in){opacity:0;transform:translateY(34px)}
  .js .stats.reveal .stat{transition:opacity .7s,transform .7s;transition-delay:calc(var(--i,0) * .12s)}
  .js .stats.reveal:not(.in) .stat{opacity:0;transform:translateY(18px)}
  .js .steps.reveal li{transition:opacity .7s,transform .7s cubic-bezier(.2,.8,.2,1),box-shadow .3s;transition-delay:calc(var(--i,0) * .12s)}
  .js .steps.reveal:not(.in) li{opacity:0;transform:translateY(24px)}
  .js .tl li.reveal:not(.in){transform:translateX(-24px)}
  .js .tl li.reveal time::before{transition:transform .5s .3s cubic-bezier(.3,1.6,.5,1)}
  .js .tl li.reveal:not(.in) time::before{transform:scale(0)}

  .js .spread.reveal:not(.in){transform:translateY(40px)}
  .js .spread.reveal .photo{transition:opacity .6s .15s,transform .9s .15s cubic-bezier(.2,.9,.3,1.2),box-shadow .5s}
  .js .spread.reveal:not(.in) .photo{opacity:0;transform:translateY(-30px) rotate(-9deg) scale(1.08)}
  .js .spread.flip.reveal:not(.in) .photo{transform:translateY(-30px) rotate(9deg) scale(1.08)}
  .js .spread.reveal .tape{transition:transform .45s .85s cubic-bezier(.3,1.4,.5,1),opacity .3s .85s}
  .js .spread.reveal:not(.in) .tape{opacity:0;transform:translateX(-50%) rotate(-3deg) scaleX(.2)}
  .js .spread.reveal .page-text>*{transition:opacity .6s,transform .6s cubic-bezier(.2,.8,.2,1);transition-delay:calc(var(--i,0) * .07s + .25s)}
  .js .spread.reveal:not(.in) .page-text>*{opacity:0;transform:translateY(16px)}
  .js .contact-in.reveal .contact-art{transition:transform .9s .2s cubic-bezier(.2,.9,.3,1.2),opacity .6s .2s}
  .js .contact-in.reveal:not(.in) .contact-art{opacity:0;transform:rotate(8deg) translateY(30px)}
}

/* ---------- responsive ---------- */
@media (max-width:900px){
  .hero{grid-template-columns:1fr}
  .hero-art{order:-1;max-width:560px;margin-inline:auto}
  .spread{grid-template-columns:1fr}
  .spread::before{display:none}
  .spread .page-art,.spread.flip .page-art{order:0;border-radius:10px 10px 0 0;background:var(--sheet);padding-bottom:12px}
  .spread .page-text,.spread.flip .page-text{order:1;border-radius:0 0 10px 10px;background:var(--sheet);padding-top:14px}
  .photo{width:min(100%,380px)}
  .photo.tall{width:min(74%,280px)}
  .collage{width:min(94%,440px)}
  .steps{grid-template-columns:repeat(2,minmax(0,1fr))}
  .kit{grid-template-columns:1fr}
  .contact-in{grid-template-columns:1fr}
  .contact-art.qr{justify-self:start;max-width:300px}
}
@media (max-width:600px){
  body{font-size:15px}
  .brand-name{display:none}
  .top nav{gap:14px;font-size:14px}
  .hero{padding-top:22px}
  .stats{grid-template-columns:1fr}
  .stat{flex-direction:row;align-items:baseline;gap:14px;padding:13px 2px}
  .stat b{min-width:3.6em;font-size:28px}
  .stat+.stat{border-left:0;border-top-color:var(--rule)}
  .did li,:root[data-lang=en] .did li{grid-template-columns:1fr}
  .flow{grid-column:1}
  .steps{grid-template-columns:1fr}
  .tl li{grid-template-columns:1fr;gap:4px}
  .visit+.visit{margin-left:0}
  .page-text .visit{display:flex;width:fit-content}
}
@media (max-width:370px){.top nav a:nth-child(2){display:none}}
@media (prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{transition:none!important;animation:none!important}}
.stat b span,.results b span,.stat b small,.results b small{font-size:inherit;color:inherit;font-weight:inherit}