:root{
  --bg:#ffffff;
  --bg-alt:#f7f8fb;
  --text:#141821;
  --muted:#5b6472;
  --line:#e6e9f0;
  --accent:#3b5bdb;
  --accent-2:#12b886;
  --accent-soft:#eef2ff;
  --radius:16px;
  --shadow:0 1px 2px rgba(16,24,40,.04),0 12px 32px -12px rgba(16,24,40,.16);
  --maxw:1180px;
}

*{box-sizing:border-box}
html{scroll-behavior:smooth;scroll-padding-top:80px}
body{
  margin:0;background:var(--bg);color:var(--text);
  font-family:'Inter',-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,'Helvetica Neue',Arial,'PingFang SC','Microsoft YaHei',sans-serif;
  font-size:17px;line-height:1.7;-webkit-font-smoothing:antialiased;
}
a{color:var(--accent);text-decoration:none}
a:hover{text-decoration:underline}
img{max-width:100%;display:block}
sup{font-size:.65em;font-weight:600;color:var(--accent)}

.container{width:100%;max-width:var(--maxw);margin:0 auto;padding:0 24px}
.container-narrow{max-width:880px}
.container-wide{max-width:1320px}
.muted{color:var(--muted)}

/* ---------- NAV ---------- */
.nav{
  position:sticky;top:0;z-index:60;background:rgba(255,255,255,.82);
  backdrop-filter:saturate(160%) blur(12px);border-bottom:1px solid transparent;
  transition:border-color .2s ease, box-shadow .2s ease;
}
.nav.scrolled{border-color:var(--line);box-shadow:0 1px 12px rgba(16,24,40,.05)}
.nav-inner{max-width:var(--maxw);margin:0 auto;padding:12px 24px;display:flex;align-items:center;gap:20px}
.nav-brand{display:flex;align-items:baseline;gap:10px;text-decoration:none!important}
.logo{font-weight:800;letter-spacing:-.02em;font-size:20px;color:var(--text);
  background:linear-gradient(95deg,var(--accent),var(--accent-2));-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent}
.nav-venue{font-size:12px;color:var(--muted);font-weight:500;letter-spacing:.02em}
.nav-links{margin-left:auto;display:flex;gap:22px}
.nav-links a{color:var(--muted);font-size:14.5px;font-weight:500;text-decoration:none}
.nav-links a:hover{color:var(--text)}
.nav-toggle{display:none;background:none;border:0;color:var(--text);cursor:pointer;margin-left:auto;padding:6px}

/* ---------- HERO ---------- */
.hero{position:relative;padding:64px 0 8px;text-align:center;overflow:hidden}
.hero-bg{
  position:absolute;inset:-200px 0 auto 0;height:620px;z-index:-1;
  background:
    radial-gradient(600px 320px at 20% 30%, rgba(59,91,219,.13), transparent 60%),
    radial-gradient(620px 330px at 80% 20%, rgba(18,184,134,.12), transparent 60%),
    radial-gradient(500px 300px at 50% 70%, rgba(124,58,237,.08), transparent 60%);
  filter:blur(6px);
}
.badge{
  display:inline-block;padding:6px 14px;border-radius:999px;background:var(--accent-soft);
  color:var(--accent);font-size:13px;font-weight:600;letter-spacing:.01em;border:1px solid #dce3ff;
}
.title{
  margin:22px auto 14px;max-width:1000px;font-size:clamp(30px,4.4vw,52px);line-height:1.15;
  font-weight:800;letter-spacing:-.028em;
}
.title-accent{background:linear-gradient(95deg,var(--accent),var(--accent-2));-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent}
.subtitle{max-width:760px;margin:0 auto 26px;color:var(--muted);font-size:18px}

.authors{display:flex;flex-wrap:wrap;justify-content:center;gap:6px 18px;margin:0 auto 14px;max-width:920px}
.author{font-size:16.5px;font-weight:500}
.author a{color:var(--text)}
.author a:hover{color:var(--accent)}
.corr{color:var(--accent-2);font-size:.8em;margin-left:2px}
.lead-mark{color:var(--accent);font-size:.58em;margin-left:3px;vertical-align:super;line-height:1}
.affiliations{color:var(--muted);font-size:14.5px;line-height:1.6;max-width:900px;margin:0 auto}
.corr-note{margin-top:6px;font-size:13px}

.buttons{display:flex;flex-wrap:wrap;justify-content:center;gap:12px;margin:30px 0 44px}
.btn{
  display:inline-flex;align-items:center;gap:9px;padding:11px 20px;border-radius:999px;
  font-size:15px;font-weight:600;text-decoration:none!important;transition:.18s ease;border:1px solid transparent;
}
.btn .ic{width:17px;height:17px;flex:none}
.btn-dark{background:#151a23;color:#fff}
.btn-dark:hover{background:#2a3342;transform:translateY(-2px);box-shadow:0 8px 22px -8px rgba(16,24,40,.5)}
.btn-ghost{background:#fff;color:var(--text);border-color:var(--line)}
.btn-ghost:hover{border-color:#c8cedb;transform:translateY(-2px)}
.btn-disabled{background:#eef0f4;color:#98a1b0;pointer-events:none}
.soon{font-size:11px;font-weight:700;background:#dde1e8;color:#79828f;padding:1px 7px;border-radius:999px;text-transform:uppercase;letter-spacing:.04em}

/* ---------- FIGURES ---------- */
.figure{margin:0 0 8px;background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:14px;box-shadow:var(--shadow)}
.figure img{width:100%;height:auto;border-radius:8px;margin:0 auto;cursor:zoom-in}
.figure figcaption{margin-top:14px;color:var(--muted);font-size:14.5px;line-height:1.6;text-align:left;padding:0 6px}
.figure-plain{box-shadow:none}

/* ---------- SECTIONS ---------- */
.section{padding:74px 0}
.section-alt{background:var(--bg-alt);border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.section-title{
  font-size:clamp(24px,2.6vw,32px);font-weight:800;letter-spacing:-.022em;margin:0 0 22px;text-align:center;
}
.sub-title{font-size:20px;font-weight:700;letter-spacing:-.015em;margin:44px 0 16px}
.abstract{font-size:17.5px;line-height:1.85;text-align:justify;color:#2a303c}
.lead{color:var(--muted);font-size:16.5px;margin:0 auto 26px;text-align:center}
.note{color:var(--muted);font-size:14px;margin:12px auto 0;line-height:1.6}

/* ---------- CARDS ---------- */
.cards{display:grid;grid-template-columns:repeat(3,1fr);gap:20px;margin-top:8px}
.card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:26px 24px;box-shadow:var(--shadow);transition:.2s ease}
.card:hover{transform:translateY(-4px);box-shadow:0 18px 40px -20px rgba(16,24,40,.3)}
.card-ic{
  display:inline-flex;align-items:center;justify-content:center;width:38px;height:38px;border-radius:10px;
  background:linear-gradient(135deg,var(--accent),var(--accent-2));color:#fff;font-weight:800;font-size:14px;margin-bottom:14px
}
.card h3{margin:0 0 10px;font-size:17.5px;font-weight:700;letter-spacing:-.01em}
.card p{margin:0;font-size:15px;color:var(--muted);line-height:1.72}

.stats{display:grid;grid-template-columns:repeat(4,1fr);gap:16px;margin-top:34px}
.stat{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:22px 16px;text-align:center}
.stat-num{font-size:30px;font-weight:800;letter-spacing:-.03em;
  background:linear-gradient(95deg,var(--accent),var(--accent-2));-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent}
.stat-lbl{font-size:13.5px;color:var(--muted);line-height:1.5;margin-top:4px}

/* ---------- METHOD ---------- */
.method-grid{display:grid;grid-template-columns:1fr 1fr;gap:20px;margin:34px auto 0}
.mbox{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:24px;box-shadow:var(--shadow)}
.mbox h3{margin:8px 0 10px;font-size:17px;font-weight:700}
.mbox p{font-size:15px;color:var(--muted);margin:0 0 12px;line-height:1.7}
.mtag{display:inline-block;font-size:11px;font-weight:700;letter-spacing:.06em;text-transform:uppercase;padding:3px 9px;border-radius:6px;background:#eef0f4;color:#6b7484}
.mtag-red{background:#ffeceb;color:#d6453c}
.mtag-blue{background:#e8efff;color:#3b5bdb}
.mtag-green{background:#e6f8f1;color:#0f9d70}
.eq{
  background:#0f1420;color:#e7ecf5;border-radius:10px;padding:14px 16px;font-family:'JetBrains Mono',ui-monospace,SFMono-Regular,Menlo,monospace;
  font-size:13.5px;line-height:1.9;overflow-x:auto;display:flex;flex-wrap:wrap;align-items:center;gap:8px
}
.eq-center{justify-content:center;text-align:center}
.eq-l{color:#8ab4ff}
.eq-sum{color:#7ee2b8}
.eq sub,.eq sup{font-size:.75em}
.ticks{margin:0;padding-left:0;list-style:none}
.ticks li{position:relative;padding-left:24px;margin-bottom:10px;font-size:15px;color:var(--muted);line-height:1.65}
.ticks li:before{content:"";position:absolute;left:0;top:9px;width:10px;height:10px;border-radius:3px;background:linear-gradient(135deg,var(--accent),var(--accent-2))}

/* ---------- TABLES ---------- */
.table-wrap{overflow-x:auto;border:1px solid var(--line);border-radius:var(--radius);background:#fff;box-shadow:var(--shadow);margin:0 auto}
.tbl{width:100%;border-collapse:collapse;font-size:14.5px;min-width:520px}
.tbl th,.tbl td{padding:11px 14px;text-align:center;border-bottom:1px solid var(--line);white-space:nowrap}
.tbl thead th{background:#f3f5f9;font-weight:700;font-size:13.5px;color:#3a424f}
.tbl thead tr:first-child th{border-bottom:1px solid var(--line)}
.tbl tbody td:first-child,.tbl thead th:first-child{text-align:left;font-weight:600}
.tbl tbody tr:last-child td{border-bottom:0}
.tbl-res{min-width:760px}
.tbl tbody tr.ours{background:linear-gradient(90deg,rgba(59,91,219,.06),rgba(18,184,134,.05))}
.tbl tbody tr.ours td:first-child{color:var(--accent)}
.tbl tbody tr:hover{background:#f7f9fd}
.tbl tbody tr.ours:hover{background:linear-gradient(90deg,rgba(59,91,219,.1),rgba(18,184,134,.08))}
.pill{display:inline-block;padding:2px 10px;border-radius:999px;background:#eef0f4;color:#6b7484;font-size:12.5px;font-weight:600}
.pill-green{background:#e6f8f1;color:#0f9d70}
.pill-blue{background:#e8efff;color:#3b5bdb}

.tabs{display:flex;gap:8px;justify-content:center;margin-bottom:18px;flex-wrap:wrap}
.tab{
  border:1px solid var(--line);background:#fff;color:var(--muted);padding:8px 18px;border-radius:999px;
  font-size:14.5px;font-weight:600;cursor:pointer;font-family:inherit;transition:.18s ease
}
.tab:hover{border-color:#c8cedb;color:var(--text)}
.tab.active{background:#151a23;border-color:#151a23;color:#fff}
.tabpanel{display:none}
.tabpanel.active{display:block;animation:fade .25s ease}
@keyframes fade{from{opacity:0;transform:translateY(6px)}to{opacity:1;transform:none}}

.two-col{display:grid;grid-template-columns:1.15fr .85fr;gap:36px;align-items:start;margin-top:8px}

/* ---------- FOOTER ---------- */
.footer{padding:42px 0;text-align:center}
.footer p{margin:6px 0;font-size:14px;color:var(--muted)}

/* ---------- LIGHTBOX ---------- */
.lightbox{
  position:fixed;inset:0;background:rgba(8,11,18,.92);z-index:200;display:none;
  align-items:center;justify-content:center;padding:36px;cursor:zoom-out
}
.lightbox.open{display:flex}
.lightbox img{max-width:96vw;max-height:92vh;border-radius:8px;object-fit:contain}
.lb-close{position:absolute;top:16px;right:24px;background:none;border:0;color:#fff;font-size:38px;line-height:1;cursor:pointer;opacity:.8}
.lb-close:hover{opacity:1}

/* ---------- RESPONSIVE ---------- */
@media (max-width:980px){
  .cards{grid-template-columns:1fr}
  .stats{grid-template-columns:repeat(2,1fr)}
  .method-grid{grid-template-columns:1fr}
  .two-col{grid-template-columns:1fr}
}
@media (max-width:720px){
  body{font-size:16px}
  .nav-links{
    display:none;position:absolute;top:100%;left:0;right:0;background:#fff;border-bottom:1px solid var(--line);
    flex-direction:column;gap:0;padding:8px 24px 16px
  }
  .nav-links.open{display:flex}
  .nav-links a{padding:10px 0;border-bottom:1px solid var(--line)}
  .nav-toggle{display:block}
  .hero{padding:40px 0 4px}
  .section{padding:54px 0}
  .buttons{gap:9px}
  .btn{padding:10px 16px;font-size:14px}
  .d-md{display:none}
  .abstract{text-align:left}
}