:root{
  --bg:#f4f2ed; --card:#fffdf8; --ink:#1d1d1f; --muted:#615e58; --line:#e5ddcc;
  --section:#efe9da; --gold:#8a6d00; --gold-ink:#fff8e1; --btn:#1d1d1f; --btn-ink:#f5f2ea;
  --softband:linear-gradient(180deg,#efe9da 0%,#f4f2ed 100%);
  --shadow:0 1px 2px rgba(29,29,31,.05),0 12px 32px rgba(29,29,31,.06);
}
[data-theme="dark"]{
  --bg:#141416; --card:#1d1d20; --ink:#f0ede7; --muted:#a8a49a; --line:#33322e;
  --section:#1a1a1c; --gold:#d9b845; --gold-ink:#1d1d1f; --btn:#f0ede7; --btn-ink:#141416;
  --softband:linear-gradient(180deg,#1d1d20 0%,#141416 100%);
  --shadow:0 1px 2px rgba(0,0,0,.4),0 12px 32px rgba(0,0,0,.35);
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0; background:var(--bg); color:var(--ink);
  font-family:-apple-system,BlinkMacSystemFont,"SF Pro Text","Helvetica Neue","Segoe UI",Arial,sans-serif;
  -webkit-font-smoothing:antialiased; line-height:1.55;
}
a{color:var(--gold); text-decoration:none}
a:hover{text-decoration:underline}
.wrap{max-width:1024px; margin:0 auto; padding:0 20px}
header.nav{
  position:sticky; top:0; z-index:50; height:52px;
  backdrop-filter:blur(20px); -webkit-backdrop-filter:blur(20px);
  background:color-mix(in srgb, var(--bg) 78%, transparent);
  border-bottom:1px solid var(--line);
}
.nav-in{max-width:1024px; margin:0 auto; padding:0 20px; height:52px; display:flex; align-items:center; gap:14px}
.logo{display:flex; align-items:center; gap:9px; font-weight:800; letter-spacing:-.02em; font-size:17px; color:var(--ink)}
.logo:hover{text-decoration:none}
.logo-mark{width:26px; height:26px; border-radius:8px; background:var(--ink); color:var(--bg); display:grid; place-items:center; font-size:13px; font-weight:800}
.logo em{font-style:normal; color:var(--gold)}
.nav nav{margin-left:auto; display:flex; gap:18px; align-items:center; font-size:14px}
.nav nav a{color:var(--muted)}
.icon-btn{
  border:1px solid var(--line); background:var(--card); color:var(--ink);
  border-radius:980px; padding:5px 12px; font-size:13px; cursor:pointer;
}
.hero{background:var(--softband); border-bottom:1px solid var(--line); position:relative; overflow:hidden}
.hero-in{padding:72px 20px 56px; text-align:center; position:relative}
.eyebrow{color:var(--gold); font-weight:700; letter-spacing:.14em; font-size:13px; text-transform:uppercase}
h1.display{
  font-family:"SF Pro Rounded","Hiragino Maru Gothic ProN",ui-rounded,-apple-system,system-ui,sans-serif;
  font-size:clamp(40px,7vw,68px); line-height:1.04; font-weight:800; letter-spacing:-.02em; margin:14px 0 16px;
}
.lede{color:var(--muted); font-size:clamp(16px,2.4vw,20px); max-width:640px; margin:0 auto}
.tool-card{
  max-width:720px; margin:34px auto 0; background:var(--card); border:1px solid var(--line);
  border-radius:18px; box-shadow:var(--shadow); padding:18px;
}
.tool-row{display:flex; gap:10px}
.tool-row input{
  flex:1; min-width:0; border:1px solid var(--line); border-radius:980px; padding:13px 20px;
  font-size:16px; background:var(--bg); color:var(--ink); outline:none;
}
.tool-row input:focus{border-color:var(--gold)}
.btn{
  border:none; cursor:pointer; border-radius:980px; padding:13px 26px; font-size:16px; font-weight:600;
  background:var(--btn); color:var(--btn-ink); white-space:nowrap;
}
.btn:hover{opacity:.88}
.btn.gold{background:var(--gold); color:var(--gold-ink)}
.btn.ghost{background:transparent; color:var(--ink); border:1px solid var(--line)}
.btn[disabled]{opacity:.5; cursor:wait}
.tip{color:var(--muted); font-size:13.5px; margin-top:12px}
.tip code{background:var(--section); padding:1px 7px; border-radius:6px; font-size:12.5px}
.chips{display:flex; gap:8px; justify-content:center; flex-wrap:wrap; margin-top:14px}
.chip{border:1px solid var(--line); background:var(--card); color:var(--muted); border-radius:980px; padding:5px 13px; font-size:13px; cursor:pointer}
.chip:hover{color:var(--ink); border-color:var(--gold)}
.err{display:none; margin-top:14px; color:#b3261e; font-size:14.5px}
section.block{padding:56px 0 8px}
h2.sec{
  font-family:"SF Pro Rounded","Hiragino Maru Gothic ProN",ui-rounded,-apple-system,system-ui,sans-serif;
  font-size:clamp(26px,4vw,36px); font-weight:800; letter-spacing:-.02em; margin:0 0 8px;
}
.sub{color:var(--muted); margin:0 0 26px; max-width:640px}
.cards{display:grid; grid-template-columns:repeat(auto-fit,minmax(220px,1fr)); gap:14px}
.card{background:var(--card); border:1px solid var(--line); border-radius:18px; padding:20px; box-shadow:var(--shadow)}
.card h3{margin:0 0 6px; font-size:17px}
.card p{margin:0; color:var(--muted); font-size:14.5px}
.card .num{display:inline-grid; place-items:center; width:26px; height:26px; border-radius:50%; background:var(--ink); color:var(--bg); font-size:13.5px; font-weight:700; margin-bottom:10px}
pre.api{
  background:var(--card); border:1px solid var(--line); border-radius:18px; padding:18px 20px;
  overflow-x:auto; font-size:14px; box-shadow:var(--shadow);
}
pre.api code{color:var(--ink)}
.faq details{background:var(--card); border:1px solid var(--line); border-radius:14px; padding:14px 18px; margin-bottom:10px}
.faq summary{cursor:pointer; font-weight:600}
.faq p{color:var(--muted); margin:8px 0 2px}
footer{border-top:1px solid var(--line); margin-top:64px; padding:34px 0 46px; color:var(--muted); font-size:14px}
footer .cols{display:flex; gap:34px; flex-wrap:wrap}
footer a{color:var(--muted)}
/* reader */
#reader{display:none; padding:34px 0 10px}
.reader-card{background:var(--card); border:1px solid var(--line); border-radius:18px; box-shadow:var(--shadow); padding:30px clamp(18px,4vw,44px)}
.reader-meta{display:flex; gap:12px; align-items:center; color:var(--muted); font-size:14px; flex-wrap:wrap}
.reader-meta img{width:38px; height:38px; border-radius:50%}
.export-bar{display:flex; gap:8px; flex-wrap:wrap; margin:20px 0 6px}
.export-bar .btn{padding:9px 18px; font-size:14px}
article.md-body{font-size:17px; line-height:1.75; word-wrap:break-word}
article.md-body h1{font-size:30px; line-height:1.25; letter-spacing:-.01em}
article.md-body h2{font-size:24px; margin-top:1.6em}
article.md-body h3{font-size:20px}
article.md-body img{max-width:100%; border-radius:12px}
article.md-body blockquote{border-left:3px solid var(--gold); margin:1em 0; padding:2px 0 2px 16px; color:var(--muted)}
article.md-body code{background:var(--section); padding:1px 6px; border-radius:6px; font-size:.9em}
article.md-body pre{background:var(--section); border-radius:12px; padding:14px 16px; overflow-x:auto}
article.md-body pre code{background:transparent; padding:0}
article.md-body table{border-collapse:collapse; width:100%; overflow-x:auto; display:block}
article.md-body th,article.md-body td{border:1px solid var(--line); padding:7px 10px; font-size:15px; text-align:left}
article.md-body hr{border:none; border-top:1px solid var(--line); margin:2em 0}
.spin{display:inline-block; width:15px; height:15px; border:2px solid var(--btn-ink); border-top-color:transparent; border-radius:50%; animation:sp 0.7s linear infinite; vertical-align:-2px; margin-right:8px}
@keyframes sp{to{transform:rotate(360deg)}}
@media (max-width:560px){ .tool-row{flex-direction:column} .tool-row .btn{width:100%} }
@media print{ header.nav,.hero,.export-bar,footer,section.block{display:none!important} #reader{display:block!important} body{background:#fff} }