:root{
  --bg:#faf6ef; --card:#ffffff; --ink:#1b1a2e; --muted:#6b6880; --line:#e7e0d4;
  --amber:#ff9838; --indigo:#6c63ff; --amber2:#ff7a45;
  --radius:16px; --max:1080px;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:var(--bg);color:var(--ink);
  font-family:"Trebuchet MS",Verdana,system-ui,sans-serif;line-height:1.6;-webkit-font-smoothing:antialiased}
@media(prefers-color-scheme:dark){
  :root{--bg:#16151f;--card:#1f1d2c;--ink:#f2eefa;--muted:#a49fbb;--line:#302d43}
}
h1,h2,h3{margin:0 0 .4em;line-height:1.15}
a{color:inherit}
.skip{position:absolute;left:-9999px}
.skip:focus{left:12px;top:12px;background:var(--indigo);color:#fff;padding:8px 14px;border-radius:8px;z-index:9}
.u{color:var(--amber);text-decoration:underline;text-decoration-color:var(--amber);text-underline-offset:5px}

/* header */
.top{max-width:var(--max);margin:0 auto;display:flex;justify-content:space-between;align-items:center;gap:14px;padding:18px 22px}
.brand{display:flex;gap:11px;align-items:center;text-decoration:none}
.bt{font-size:19px;font-weight:700}
.bt b{color:var(--amber)}
.bt i{display:block;font-style:normal;font-size:11px;letter-spacing:1px;color:var(--muted);text-transform:uppercase}
.topnav{display:flex;gap:20px;align-items:center;font-size:15px}
.topnav a{color:var(--muted);text-decoration:none}
.topnav a:hover{color:var(--ink)}
.topnav .pill{background:var(--indigo);color:#fff;padding:8px 15px;border-radius:999px;font-weight:600}

/* hero */
.hero{max-width:820px;margin:34px auto 10px;padding:0 22px;text-align:center}
.badge{display:inline-block;background:var(--card);border:1px solid var(--line);color:var(--muted);
  padding:6px 14px;border-radius:999px;font-size:13px;margin-bottom:18px}
.hero h1{font-size:clamp(32px,5.2vw,54px);font-weight:800;letter-spacing:-1px}
.sub{color:var(--muted);font-size:18px;max-width:56ch;margin:16px auto 0}

/* app */
.app{max-width:900px;margin:34px auto;padding:0 22px}
.tabs{display:flex;gap:8px;margin-bottom:14px}
.tab{flex:0 0 auto;background:var(--card);border:1px solid var(--line);color:var(--muted);
  padding:11px 20px;border-radius:12px;cursor:pointer;font:inherit;font-size:15px;font-weight:600;transition:.2s}
.tab:hover{color:var(--ink)}
.tab.active{background:var(--ink);color:var(--bg);border-color:var(--ink)}
.drop{background:var(--card);border:2px dashed var(--line);border-radius:var(--radius);
  padding:52px 20px;text-align:center;cursor:pointer;display:flex;flex-direction:column;gap:4px;align-items:center;transition:.2s}
.drop:hover,.drop:focus,.drop.drag{border-color:var(--amber);outline:none;transform:translateY(-2px)}
.di{font-size:40px}
.drop b{font-size:20px}
.drop small{color:var(--muted)}
.drop u{color:var(--amber)}
.panel{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:22px}
.tname{font-weight:700;color:var(--indigo);margin:0 0 12px;word-break:break-all}
.wave{width:100%;height:140px;background:linear-gradient(180deg,rgba(108,99,255,.06),transparent);
  border:1px solid var(--line);border-radius:12px;display:block}
.ctl{margin-top:16px}
.row{display:flex;gap:14px;align-items:center;flex-wrap:wrap;margin:12px 0}
.row.end{justify-content:flex-start;border-top:1px solid var(--line);padding-top:16px;margin-top:18px}
.seg{display:flex;gap:6px;flex-wrap:wrap}
.s{background:var(--bg);border:1px solid var(--line);color:var(--muted);padding:8px 14px;border-radius:999px;cursor:pointer;font:inherit;font-size:14px}
.s.active{background:linear-gradient(90deg,var(--amber),var(--amber2));color:#241300;border-color:transparent;font-weight:700}
.sl{gap:22px}
.sl label{display:flex;flex-direction:column;gap:5px;font-size:14px;color:var(--muted);flex:1;min-width:180px}
.sl input[type=range]{accent-color:var(--indigo)}
.sl span{color:var(--amber);font-weight:700}
.b{border:0;cursor:pointer;font:inherit;font-weight:700;padding:12px 20px;border-radius:11px;font-size:15px;transition:.2s}
.b.main{background:linear-gradient(90deg,var(--amber),var(--amber2));color:#241300}
.b.main:hover{filter:brightness(1.05);transform:translateY(-1px)}
.b.ghost{background:transparent;border:1px solid var(--line);color:var(--ink)}
.b.ghost:hover{border-color:var(--indigo)}
.st{color:var(--muted);font-size:14px}

/* why + faq */
.why,.faq{max-width:var(--max);margin:64px auto;padding:0 22px}
.why h2,.faq h2{text-align:center;font-size:clamp(24px,3.4vw,34px);font-weight:800;margin-bottom:26px}
.cards{display:grid;grid-template-columns:repeat(4,1fr);gap:16px}
.c{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:22px}
.c span{font-size:26px}
.c h3{font-size:17px;margin:8px 0 4px}
.c p{color:var(--muted);font-size:14px;margin:0}
.faq details{background:var(--card);border:1px solid var(--line);border-radius:12px;padding:2px 18px;max-width:720px;margin:10px auto}
.faq summary{cursor:pointer;font-weight:700;padding:14px 0;list-style:none}
.faq summary::-webkit-details-marker{display:none}
.faq summary::after{content:"+";float:right;color:var(--amber);font-size:20px}
.faq details[open] summary::after{content:"–"}
.faq p{color:var(--muted);margin:0 0 16px}

.foot{border-top:1px solid var(--line);margin-top:60px;padding:30px 22px;text-align:center;color:var(--muted)}
.foot b{color:var(--amber)}
.foot a{text-decoration:none;color:var(--muted)}
.foot nav{display:flex;gap:18px;justify-content:center;margin:12px 0}
.foot small{font-size:13px}

@media(max-width:820px){.cards{grid-template-columns:1fr 1fr}.topnav a:not(.pill){display:none}}
@media(max-width:480px){.cards{grid-template-columns:1fr}}

/* cross-link header buttons hover (CSP-safe) */
.xlink{transition:border-color .2s}
.xlink:hover{border-color:#7c5cff!important}

/* AI (beta) separation */
.ai-row{display:flex;align-items:center;gap:12px;flex-wrap:wrap;margin:6px 0 4px}
.b.ai{background:linear-gradient(90deg,#ff9838,#6c63ff);color:#fff}
.b.ai:hover:not(:disabled){filter:brightness(1.06);transform:translateY(-1px)}
.b.ai:disabled{opacity:.5;cursor:not-allowed}
.ai-prog{display:flex;align-items:center;gap:12px;margin:6px 0;background:var(--bg);border:1px solid var(--line);border-radius:8px;padding:8px 12px}
.ai-prog .ai-bar{height:8px;border-radius:6px;background:linear-gradient(90deg,#ff9838,#6c63ff);width:0;min-width:2px;transition:width .2s}
.ai-prog span{color:var(--muted);font-size:14px;white-space:nowrap}