:root{
  --ink:#16202a;--muted:#5b6773;--line:#e3e7eb;--bg:#fbfaf7;--card:#fff;
  --accent:#0f6b5c;--accent-ink:#fff;--warn:#b4532a;
  --radius:14px;--max:1080px;
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:var(--bg);color:var(--ink);line-height:1.6;font-size:17px}
a{color:var(--accent)}
.wrap{max-width:var(--max);margin:0 auto;padding:0 20px}
header.top{border-bottom:1px solid var(--line);background:#fff}
header.top .wrap{display:flex;align-items:center;justify-content:space-between;height:64px}
.brand{font-weight:700;letter-spacing:-.01em;text-decoration:none;color:var(--ink)}
.brand span{color:var(--accent)}
nav a{margin-left:18px;text-decoration:none;color:var(--muted);font-size:15px}
nav a.lang{border:1px solid var(--line);padding:5px 10px;border-radius:999px;color:var(--ink)}
.hero{padding:72px 0 56px}
.eyebrow{display:inline-block;font-size:13px;font-weight:600;letter-spacing:.06em;text-transform:uppercase;color:var(--accent);margin-bottom:14px}
h1{font-size:clamp(32px,5vw,52px);line-height:1.12;letter-spacing:-.02em;margin:0 0 18px;max-width:18ch}
.zh h1{max-width:16em;letter-spacing:0}
.lede{font-size:clamp(18px,2.2vw,21px);color:var(--muted);max-width:40em;margin:0 0 28px}
.btn{display:inline-block;background:var(--accent);color:var(--accent-ink);padding:14px 22px;border-radius:10px;font-weight:600;text-decoration:none}
.btn.ghost{background:transparent;color:var(--ink);border:1px solid var(--line);margin-left:10px}
.chat{margin-top:44px;background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:22px;max-width:640px;box-shadow:0 1px 0 rgba(0,0,0,.02)}
.chat .q{font-weight:600;margin-bottom:10px}
.chat .a{color:var(--muted)}
.chat .a b{color:var(--ink)}
.chat .you{margin-top:12px;padding:10px 12px;border-radius:8px;background:#fdf1eb;color:var(--warn);font-size:15px}
/* hero before/after mock (illustrative) */
.hero .wrap{display:grid;grid-template-columns:1.05fr 1fr;gap:40px;align-items:center}
.ba{display:grid;gap:12px}
.ba-label{font-size:12px;color:var(--muted);text-align:right}
.ba{position:relative}
.ba .corner{position:absolute;top:-12px;right:-6px;z-index:2;background:var(--warn);color:#fff;font-size:12px;font-weight:700;letter-spacing:.04em;padding:5px 12px;border-radius:999px;box-shadow:0 2px 8px rgba(0,0,0,.15);transform:rotate(3deg)}
.chatbox{position:relative;overflow:hidden}
.chatbox.after::after{content:attr(data-corner);position:absolute;top:14px;right:-34px;transform:rotate(45deg);background:var(--accent);color:#fff;font-size:11px;font-weight:700;letter-spacing:.08em;padding:4px 40px}
.chatbox{background:#fff;border:1px solid var(--line);border-radius:14px;padding:14px 16px;box-shadow:0 8px 24px rgba(0,0,0,.05);font-size:14px}
.chatbox .tag{display:inline-block;font-size:11px;font-weight:700;letter-spacing:.06em;text-transform:uppercase;padding:3px 8px;border-radius:999px;margin-bottom:8px}
.chatbox.before .tag{background:#f3f4f6;color:#6b7280}
.chatbox.after .tag{background:#e6f4f1;color:var(--accent)}
.chatbox .u{display:flex;gap:8px;align-items:flex-start;margin-bottom:10px;color:var(--ink)}
.chatbox .u i,.chatbox .r i{flex:none;width:22px;height:22px;border-radius:50%;display:grid;place-items:center;font-style:normal;font-size:11px;font-weight:700}
.chatbox .u i{background:#e5e7eb}
.chatbox .r{display:flex;gap:8px;align-items:flex-start}
.chatbox .r i{background:#111;color:#fff}
.chatbox ol{margin:4px 0 0;padding-left:18px;color:#374151}
.chatbox ol li{margin:3px 0}
.chatbox ol li.you{background:#e6f4f1;border-radius:6px;padding:4px 6px;margin-left:-6px;color:var(--ink);font-weight:600}
.chatbox ol li.you small{display:block;font-weight:400;color:var(--muted);font-size:12px}
.chatbox .cite{margin-top:8px;font-size:12px;color:var(--accent);background:#e6f4f1;display:inline-block;padding:3px 8px;border-radius:6px}
.chatbox .miss{margin-top:8px;font-size:12px;color:var(--warn)}
/* pricing */
.tiers{display:grid;gap:18px;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));margin-bottom:18px}
.tier{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:22px;position:relative}
.tier.hot{border-color:var(--accent);box-shadow:0 0 0 3px #e6f4f1}
.tier .badge{position:absolute;top:-12px;left:20px;background:var(--accent);color:#fff;font-size:12px;font-weight:700;padding:4px 10px;border-radius:999px}
.tier h3{margin:0 0 4px;font-size:19px}
.tier .price{font-size:32px;font-weight:700;letter-spacing:-.02em;margin:6px 0 2px}
.tier .price small{font-size:14px;font-weight:500;color:var(--muted)}
.tier ul{margin:12px 0 0;padding-left:18px;color:var(--muted);font-size:15px}
.tier ul li{margin:4px 0}
.onetime{display:grid;gap:14px;grid-template-columns:repeat(auto-fit,minmax(260px,1fr))}
.onetime .card .price{font-size:24px;font-weight:700;margin:4px 0 6px}
.guarantee{background:#fff;border-left:4px solid var(--accent);border-radius:0 var(--radius) var(--radius) 0;padding:18px 22px;margin-top:22px}
.guarantee b{display:block;margin-bottom:6px}
.guarantee p{margin:0;color:var(--muted)}
.diff{display:grid;gap:18px;grid-template-columns:repeat(auto-fit,minmax(260px,1fr))}
.diff .n{font-size:13px;font-weight:700;color:var(--accent);letter-spacing:.06em}
section{padding:56px 0;border-top:1px solid var(--line)}
h2{font-size:clamp(24px,3.4vw,34px);letter-spacing:-.01em;margin:0 0 10px}
.sub{color:var(--muted);margin:0 0 30px;max-width:44em}
.grid{display:grid;gap:18px;grid-template-columns:repeat(auto-fit,minmax(240px,1fr))}
.card{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:22px}
.card h3{margin:0 0 8px;font-size:19px}
.card p{margin:0;color:var(--muted);font-size:16px}
.stat{font-size:40px;font-weight:700;color:var(--accent);letter-spacing:-.02em;line-height:1}
.stat-src{display:block;margin-top:10px;font-size:13px;color:var(--muted)}
ol.steps{counter-reset:s;list-style:none;padding:0;margin:0;display:grid;gap:14px}
ol.steps li{counter-increment:s;background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:18px 18px 18px 64px;position:relative}
ol.steps li::before{content:counter(s);position:absolute;left:18px;top:16px;width:30px;height:30px;border-radius:50%;background:var(--accent);color:#fff;font-weight:700;display:grid;place-items:center;font-size:15px}
ol.steps b{display:block;margin-bottom:2px}
ol.steps span{color:var(--muted);font-size:16px}
.who{display:flex;flex-wrap:wrap;gap:10px}
.who span{background:#fff;border:1px solid var(--line);border-radius:999px;padding:8px 14px;font-size:15px}
details{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:16px 20px;margin-bottom:12px}
summary{font-weight:600;cursor:pointer}
details p{color:var(--muted);margin:10px 0 0}
.cta{background:var(--ink);color:#fff;border-radius:20px;padding:44px 32px;text-align:center}
.cta h2{color:#fff}
.cta p{color:#c9d1d9;max-width:36em;margin:0 auto 24px}
.cta .btn{background:#fff;color:var(--ink)}
footer{padding:32px 0 48px;color:var(--muted);font-size:14px}
footer .wrap{display:flex;flex-wrap:wrap;justify-content:space-between;gap:12px}
@media (max-width:900px){.hero .wrap{grid-template-columns:1fr}}
@media (max-width:640px){
  nav a:not(.lang){display:none}
  .btn.ghost{margin:10px 0 0}
  .hero{padding:48px 0 40px}
}