:root{
  --bg:#f7f6f2;--surface:#ffffff;--surface-2:#efede6;--text:#1b1d21;--muted:#5d626b;
  --line:#dedad0;--accent:#e8a317;--accent-ink:#1b1d21;--brand:#1f3a4d;--brand-ink:#ffffff;
  --ok:#2f7d4f;--bad:#b3261e;--radius:14px;--shadow:0 1px 2px rgba(0,0,0,.05),0 8px 24px rgba(0,0,0,.06);
  --max:1120px;
}
@media (prefers-color-scheme:dark){:root{
  --bg:#121417;--surface:#1a1d21;--surface-2:#22262b;--text:#eceae4;--muted:#a3a7ae;
  --line:#2e3338;--accent:#f0b43a;--accent-ink:#121417;--brand:#9cc3dc;--brand-ink:#121417;
  --ok:#62c08a;--bad:#f2867e;--shadow:0 1px 2px rgba(0,0,0,.3),0 8px 24px rgba(0,0,0,.3);
}}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;background:var(--bg);color:var(--text);font:16px/1.6 system-ui,-apple-system,"Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif}
a{color:inherit}
p a,li a,td a,.link{color:var(--brand);text-underline-offset:3px}
img,svg{max-width:100%}
h1,h2,h3{line-height:1.2;letter-spacing:-.01em;margin:0 0 .5em}
h1{font-size:clamp(2rem,5vw,3.2rem)}
h2{font-size:clamp(1.5rem,3.2vw,2rem);margin-top:1.6em}
h3{font-size:1.15rem;margin-top:1.4em}
.wrap{max-width:var(--max);margin:0 auto;padding:0 16px}
.skip{position:absolute;left:-999px}.skip:focus{left:16px;top:8px;background:var(--surface);padding:8px;z-index:9}

/* header */
.top{position:sticky;top:0;z-index:5;background:color-mix(in srgb,var(--bg) 88%,transparent);backdrop-filter:blur(10px);border-bottom:1px solid var(--line)}
.top .wrap{display:flex;align-items:center;gap:16px;min-height:64px}
.brand{display:flex;align-items:center;gap:10px;text-decoration:none;font-weight:700;white-space:nowrap}
.brand svg{width:32px;height:32px;flex:none}
.brand small{display:block;font-weight:500;font-size:.72rem;color:var(--muted);letter-spacing:.04em;text-transform:uppercase}
.nav{display:flex;gap:4px;margin-left:auto;flex-wrap:wrap}
.nav a{text-decoration:none;padding:8px 10px;border-radius:8px;color:var(--muted);font-size:.95rem}
.nav a:hover,.nav a[aria-current=page]{color:var(--text);background:var(--surface-2)}
.lang{display:flex;gap:2px;border:1px solid var(--line);border-radius:999px;padding:2px}
.lang a{text-decoration:none;font-size:.8rem;padding:4px 9px;border-radius:999px;color:var(--muted)}
.lang a[aria-current=true]{background:var(--text);color:var(--bg)}
.menu-btn{display:none;margin-left:auto;background:none;border:1px solid var(--line);border-radius:8px;padding:6px 10px;color:var(--text);font:inherit}
@media (max-width:900px){
  .menu-btn{display:block}
  .nav{display:none;position:absolute;top:64px;left:0;right:0;flex-direction:column;background:var(--bg);border-bottom:1px solid var(--line);padding:8px 16px 16px}
  .nav.open{display:flex}
  .lang{margin-left:0}
}

/* buttons */
.btn{display:inline-flex;align-items:center;gap:8px;text-decoration:none;font-weight:600;padding:12px 18px;border-radius:10px;border:1px solid transparent;cursor:pointer;font-size:1rem}
.btn-primary{background:var(--accent);color:var(--accent-ink)}
.btn-primary:hover{filter:brightness(1.05)}
.btn-ghost{border-color:var(--line);background:var(--surface)}
.btn[aria-disabled=true]{opacity:.55;cursor:default}
.actions{display:flex;flex-wrap:wrap;gap:10px;margin-top:20px}

/* hero */
.hero{padding:56px 0 40px}
.hero .wrap{display:grid;grid-template-columns:1.1fr .9fr;gap:40px;align-items:center}
.eyebrow{display:inline-block;font-size:.8rem;font-weight:600;letter-spacing:.06em;text-transform:uppercase;color:var(--muted);margin-bottom:12px}
.lead{font-size:1.15rem;color:var(--muted);max-width:40em}
@media (max-width:860px){.hero .wrap{grid-template-columns:1fr}.hero{padding-top:32px}}

/* stamped photo mock */
.shot{position:relative;aspect-ratio:4/3;border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow);
  background:linear-gradient(180deg,#9fc1d9 0%,#c8dbe6 38%,#b99f73 38.5%,#9b7f55 62%,#7a6545 100%)}
.shot::before{content:"";position:absolute;left:-10%;right:-10%;top:36%;height:30%;background:linear-gradient(170deg,transparent 40%,#6f7579 41%,#5e6468 58%,transparent 59%)}
.shot::after{content:"";position:absolute;left:8%;top:22%;width:40%;height:18%;background:radial-gradient(ellipse at 50% 100%,#6a7b55 0 60%,transparent 61%)}
.stamp{position:absolute;left:0;right:0;bottom:0;padding:12px 14px;background:linear-gradient(0deg,rgba(0,0,0,.72),rgba(0,0,0,.35) 80%,transparent);color:#fff;
  font:500 clamp(.62rem,1.5vw,.78rem)/1.45 ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;text-shadow:0 1px 2px rgba(0,0,0,.6)}
.stamp b{color:#ffd166;font-weight:700}
.stamp .ok{color:#8ee0a8}

/* sections */
section{padding:40px 0}
.alt{background:var(--surface-2)}
.grid{display:grid;gap:16px;grid-template-columns:repeat(auto-fill,minmax(250px,1fr))}
.card{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:20px}
.card h3{margin-top:0}
.card p{margin:.3em 0 0;color:var(--muted)}
.icon{width:40px;height:40px;border-radius:10px;display:grid;place-items:center;background:var(--surface-2);margin-bottom:12px;font-size:1.25rem}
.tag{display:inline-block;font-size:.72rem;font-weight:700;padding:2px 8px;border-radius:999px;background:var(--surface-2);color:var(--muted);vertical-align:middle;margin-left:6px}
.tag.pro{background:#fbe7bd;color:#6b4a00}.tag.bim{background:#d5e6f2;color:#1f3a4d}
@media (prefers-color-scheme:dark){.tag.pro{background:#4a3a12;color:#f6d38a}.tag.bim{background:#203646;color:#b9d7ea}}

/* pricing */
.plans{display:grid;gap:16px;grid-template-columns:repeat(auto-fit,minmax(260px,1fr));margin-top:24px}
.plan{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:24px;display:flex;flex-direction:column}
.plan.feat{border:2px solid var(--accent)}
.price{font-size:2rem;font-weight:800;margin:.2em 0 0}
.price small{font-size:.95rem;font-weight:500;color:var(--muted)}
.plan ul{padding-left:1.1em;margin:16px 0 0}
.plan li{margin:.35em 0}
.note{font-size:.9rem;color:var(--muted)}

/* tables & prose */
.prose{max-width:820px}
.prose li{margin:.3em 0}
table{width:100%;border-collapse:collapse;margin:16px 0;font-size:.95rem}
th,td{text-align:left;padding:10px 12px;border-bottom:1px solid var(--line);vertical-align:top}
th{background:var(--surface-2);font-weight:600}
.tablewrap{overflow-x:auto;border:1px solid var(--line);border-radius:10px;background:var(--surface)}
.tablewrap table{margin:0}
code{font:.9em ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;background:var(--surface-2);padding:1px 5px;border-radius:5px}
.toc{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:16px 20px;margin:20px 0}
.toc ol{margin:0;padding-left:1.2em;columns:2;column-gap:32px}
@media (max-width:640px){.toc ol{columns:1}}
.page-head{padding:40px 0 8px}
.page-head p{color:var(--muted);max-width:44em}
.callout{border-left:4px solid var(--accent);background:var(--surface);padding:12px 16px;border-radius:0 10px 10px 0;margin:16px 0}

/* stores */
.stores{display:grid;gap:16px;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));margin-top:24px}

/* verify */
.drop{border:2px dashed var(--line);border-radius:var(--radius);padding:28px;text-align:center;background:var(--surface)}
.field{display:block;width:100%;padding:12px;border:1px solid var(--line);border-radius:10px;background:var(--surface);color:var(--text);font:14px ui-monospace,Menlo,Consolas,monospace;margin-top:8px}
.result{margin-top:16px;padding:14px 16px;border-radius:10px;display:none;word-break:break-all}
.result.ok{display:block;background:color-mix(in srgb,var(--ok) 14%,var(--surface));border:1px solid var(--ok)}
.result.bad{display:block;background:color-mix(in srgb,var(--bad) 12%,var(--surface));border:1px solid var(--bad)}
.result.info{display:block;background:var(--surface);border:1px solid var(--line)}

/* footer */
footer{border-top:1px solid var(--line);margin-top:48px;padding:32px 0;font-size:.9rem;color:var(--muted)}
footer .wrap{display:grid;gap:24px;grid-template-columns:2fr 1fr 1fr}
footer h4{margin:0 0 8px;color:var(--text);font-size:.95rem}
footer ul{list-style:none;margin:0;padding:0}
footer li{margin:.3em 0}
footer a{text-decoration:none}footer a:hover{text-decoration:underline}
@media (max-width:720px){footer .wrap{grid-template-columns:1fr}}
.page-head .plan .price,.page-head .card h3,.page-head .plan h3{color:var(--text)}
@media (prefers-color-scheme:dark){.brand svg rect{fill:#3c6a88}}
/* language selector */
.langsel{position:relative}
.langsel summary{list-style:none;cursor:pointer;border:1px solid var(--line);border-radius:999px;padding:6px 12px;font-size:.85rem;color:var(--muted);white-space:nowrap}
.langsel summary::-webkit-details-marker{display:none}
.langsel[open] summary{color:var(--text);background:var(--surface-2)}
.langlist{position:absolute;right:0;top:calc(100% + 6px);background:var(--surface);border:1px solid var(--line);border-radius:12px;box-shadow:var(--shadow);padding:6px;min-width:160px;display:flex;flex-direction:column;z-index:10}
.langlist a{text-decoration:none;padding:8px 10px;border-radius:8px;color:var(--text);font-size:.92rem}
.langlist a:hover{background:var(--surface-2)}
.langlist a[aria-current=true]{font-weight:700;background:var(--surface-2)}
@media (max-width:900px){.langsel{align-self:flex-start}.langlist{position:static;box-shadow:none;margin-top:6px}}
:lang(zh) body,html:lang(zh-Hans) body{font-family:system-ui,-apple-system,"PingFang SC","Hiragino Sans GB","Microsoft YaHei","Noto Sans SC",sans-serif}