/* ============================================================
   天帅实验室 TIANSHUAI LAB — design system
   midnight laboratory / phosphor instrument aesthetic
   ============================================================ */
:root{
  --bg:#070d16;
  --bg2:#0a1220;
  --panel:#0d1726;
  --panel2:#111e31;
  --line:#1c2c42;
  --line2:#28405e;
  --ink:#e9f2f9;
  --muted:#8ba3bb;
  --dim:#5a7189;
  --cyan:#3ee6c4;
  --cyan2:#4cc9ff;
  --amber:#ffb347;
  --amber2:#ff8f5a;
  --red:#ff6b6b;
  --phy:#4cc9ff;
  --che:#ffb347;
  --font-display:"ZCOOL QingKe HuangYou","Noto Sans SC",sans-serif;
  --font-body:"Noto Sans SC","PingFang SC","Microsoft YaHei",sans-serif;
  --font-mono:"JetBrains Mono","SFMono-Regular",Consolas,monospace;
}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  background:var(--bg);
  color:var(--ink);
  font-family:var(--font-body);
  font-size:16px;
  line-height:1.65;
  overflow-x:hidden;
  -webkit-font-smoothing:antialiased;
}
::selection{background:var(--cyan);color:#06231c}
a{color:inherit;text-decoration:none}
img,svg,canvas{display:block;max-width:100%}
button{font-family:inherit;cursor:pointer;border:none;background:none;color:inherit}
input{font-family:inherit}

/* scrollbar */
::-webkit-scrollbar{width:10px;height:10px}
::-webkit-scrollbar-track{background:var(--bg2)}
::-webkit-scrollbar-thumb{background:var(--line2);border-radius:5px}
::-webkit-scrollbar-thumb:hover{background:var(--cyan)}

/* ---------- utility ---------- */
.wrap{width:min(1240px,92vw);margin:0 auto}
.mono{font-family:var(--font-mono)}
.tag{
  display:inline-flex;align-items:center;gap:6px;
  font-family:var(--font-mono);font-size:11px;letter-spacing:.14em;
  text-transform:uppercase;color:var(--cyan);
  border:1px solid color-mix(in srgb,var(--cyan) 40%,transparent);
  padding:4px 12px;border-radius:99px;background:color-mix(in srgb,var(--cyan) 8%,transparent);
}
.tag.amber{color:var(--amber);border-color:color-mix(in srgb,var(--amber) 40%,transparent);background:color-mix(in srgb,var(--amber) 8%,transparent)}

/* ---------- nav ---------- */
.nav{
  position:fixed;inset:0 0 auto 0;z-index:100;
  backdrop-filter:blur(14px);-webkit-backdrop-filter:blur(14px);
  background:color-mix(in srgb,var(--bg) 78%,transparent);
  border-bottom:1px solid var(--line);
  transition:background .3s;
}
.nav-in{display:flex;align-items:center;justify-content:space-between;height:68px}
.brand{display:flex;align-items:center;gap:12px}
.brand-mark{
  width:40px;height:40px;border-radius:11px;display:grid;place-items:center;
  background:linear-gradient(135deg,#0f2233,#123a44);
  border:1px solid var(--line2);
  box-shadow:0 0 18px color-mix(in srgb,var(--cyan) 25%,transparent),inset 0 1px 0 rgba(255,255,255,.08);
}
.brand-mark svg{width:22px;height:22px}
.brand-name{font-family:var(--font-display);font-size:22px;letter-spacing:.06em;line-height:1}
.brand-name small{display:block;font-family:var(--font-mono);font-size:9px;letter-spacing:.32em;color:var(--dim);margin-top:3px}
.nav-links{display:flex;gap:6px;align-items:center}
.nav-links a{
  font-size:14px;color:var(--muted);padding:8px 16px;border-radius:8px;
  transition:.25s;position:relative;
}
.nav-links a:hover{color:var(--ink);background:rgba(255,255,255,.05)}
.nav-cta{
  font-family:var(--font-mono);font-size:12px;letter-spacing:.1em;
  color:#04222 !important;color:#06231c!important;background:var(--cyan);
  font-weight:700;border-radius:8px;padding:9px 18px!important;
  box-shadow:0 0 16px color-mix(in srgb,var(--cyan) 45%,transparent);
}
.nav-cta:hover{background:#6ff2d6!important}
.nav-burger{display:none;flex-direction:column;gap:5px;padding:8px}
.nav-burger span{width:22px;height:2px;background:var(--ink);border-radius:2px;transition:.3s}

/* ---------- hero ---------- */
.hero{position:relative;min-height:100svh;display:flex;align-items:center;padding:140px 0 90px;overflow:hidden}
#bg-canvas{position:absolute;inset:0;width:100%;height:100%;z-index:0}
.hero-grid-lines{
  position:absolute;inset:0;z-index:0;pointer-events:none;opacity:.5;
  background-image:linear-gradient(rgba(76,201,255,.05) 1px,transparent 1px),linear-gradient(90deg,rgba(76,201,255,.05) 1px,transparent 1px);
  background-size:56px 56px;
  mask-image:radial-gradient(ellipse 90% 80% at 50% 40%,#000 30%,transparent 75%);
  -webkit-mask-image:radial-gradient(ellipse 90% 80% at 50% 40%,#000 30%,transparent 75%);
}
.hero-in{position:relative;z-index:2;display:grid;grid-template-columns:1.15fr .85fr;gap:56px;align-items:center}
.hero-kicker{display:flex;align-items:center;gap:14px;margin-bottom:26px}
.hero-kicker .line{width:44px;height:1px;background:var(--cyan)}
.hero-kicker span{font-family:var(--font-mono);font-size:12px;letter-spacing:.3em;color:var(--cyan)}
.hero h1{
  font-family:var(--font-display);font-weight:400;
  font-size:clamp(46px,6.4vw,88px);line-height:1.08;letter-spacing:.02em;
}
.hero h1 em{
  font-style:normal;color:transparent;
  background:linear-gradient(100deg,var(--cyan) 10%,var(--cyan2) 55%,var(--amber) 110%);
  -webkit-background-clip:text;background-clip:text;
  text-shadow:0 0 44px color-mix(in srgb,var(--cyan) 35%,transparent);
}
.hero-sub{margin:26px 0 38px;max-width:520px;color:var(--muted);font-size:17px}
.hero-sub b{color:var(--ink);font-weight:600}
.hero-ctas{display:flex;gap:16px;flex-wrap:wrap}
.btn{
  display:inline-flex;align-items:center;gap:10px;
  font-size:15px;font-weight:600;padding:14px 28px;border-radius:12px;
  transition:transform .2s,box-shadow .2s,background .2s;position:relative;
}
.btn:active{transform:translateY(1px) scale(.99)}
.btn-primary{
  background:linear-gradient(120deg,var(--cyan),#2bd4ec);color:#052a24;
  box-shadow:0 8px 30px color-mix(in srgb,var(--cyan) 35%,transparent);
}
.btn-primary:hover{box-shadow:0 10px 40px color-mix(in srgb,var(--cyan) 55%,transparent);transform:translateY(-2px)}
.btn-ghost{border:1px solid var(--line2);color:var(--ink);background:rgba(255,255,255,.03)}
.btn-ghost:hover{border-color:var(--cyan);color:var(--cyan);background:color-mix(in srgb,var(--cyan) 7%,transparent)}
.hero-panel{
  position:relative;border:1px solid var(--line);border-radius:20px;
  background:linear-gradient(160deg,color-mix(in srgb,var(--panel) 88%,transparent),color-mix(in srgb,var(--bg2) 92%,transparent));
  backdrop-filter:blur(8px);
  padding:26px;box-shadow:0 30px 80px rgba(0,0,0,.5),inset 0 1px 0 rgba(255,255,255,.06);
}
.hero-panel-head{display:flex;align-items:center;justify-content:space-between;margin-bottom:18px}
.hero-panel-head .dots{display:flex;gap:7px}
.hero-panel-head .dots i{width:10px;height:10px;border-radius:50%;background:var(--line2)}
.hero-panel-head .dots i:nth-child(1){background:#ff6058}.hero-panel-head .dots i:nth-child(2){background:#febc2e}.hero-panel-head .dots i:nth-child(3){background:#28c840}
.hero-panel-head .ttl{font-family:var(--font-mono);font-size:11px;letter-spacing:.2em;color:var(--dim)}
.hero-readouts{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin-bottom:16px}
.hro{
  border:1px solid var(--line);border-radius:12px;padding:14px 16px;background:rgba(255,255,255,.02);
}
.hro .k{font-size:11px;color:var(--dim);letter-spacing:.12em;font-family:var(--font-mono);text-transform:uppercase}
.hro .v{font-family:var(--font-mono);font-size:24px;margin-top:4px;color:var(--cyan)}
.hro .v.amber{color:var(--amber)}
.hro .u{font-size:12px;color:var(--dim);margin-left:4px}
.hero-wave{border:1px solid var(--line);border-radius:12px;background:#0a1220;overflow:hidden}
.hero-wave canvas{width:100%;height:120px}
.hero-orbit{position:absolute;z-index:1;pointer-events:none}
.stat-strip{
  display:flex;gap:0;margin-top:70px;border:1px solid var(--line);border-radius:16px;overflow:hidden;
  background:color-mix(in srgb,var(--panel) 70%,transparent);backdrop-filter:blur(6px);
}
.stat{flex:1;padding:22px 26px;border-right:1px solid var(--line)}
.stat:last-child{border-right:none}
.stat .n{font-family:var(--font-display);font-size:38px;color:var(--ink);line-height:1}
.stat .n i{font-style:normal;color:var(--cyan)}
.stat .l{font-size:13px;color:var(--dim);margin-top:6px;letter-spacing:.08em}

/* ---------- sections ---------- */
.section{padding:110px 0 40px;position:relative}
.sec-head{display:flex;align-items:flex-end;justify-content:space-between;margin-bottom:52px;gap:24px;flex-wrap:wrap}
.sec-head .idx{font-family:var(--font-mono);font-size:13px;color:var(--cyan);letter-spacing:.2em;margin-bottom:12px;display:block}
.sec-head .idx.amber{color:var(--amber)}
.sec-head h2{font-family:var(--font-display);font-weight:400;font-size:clamp(32px,4vw,52px);line-height:1.15}
.sec-head p{max-width:420px;color:var(--muted);font-size:15px}

/* experiment cards */
.exp-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:22px}
.exp-card{
  position:relative;border:1px solid var(--line);border-radius:18px;overflow:hidden;
  background:linear-gradient(170deg,var(--panel),var(--bg2));
  transition:transform .35s cubic-bezier(.2,.8,.2,1),border-color .35s,box-shadow .35s;
  display:flex;flex-direction:column;
}
.exp-card:hover{transform:translateY(-8px);border-color:var(--line2);box-shadow:0 24px 60px rgba(0,0,0,.5)}
.exp-card.phy:hover{box-shadow:0 24px 60px color-mix(in srgb,var(--phy) 14%,transparent)}
.exp-card.che:hover{box-shadow:0 24px 60px color-mix(in srgb,var(--che) 14%,transparent)}
.exp-illus{
  height:180px;position:relative;overflow:hidden;display:grid;place-items:center;
  background:radial-gradient(ellipse 120% 100% at 50% 0%,rgba(76,201,255,.07),transparent 60%);
  border-bottom:1px solid var(--line);
}
.che .exp-illus{background:radial-gradient(ellipse 120% 100% at 50% 0%,rgba(255,179,71,.08),transparent 60%)}
.exp-illus svg{width:150px;height:150px;transition:transform .5s cubic-bezier(.2,.8,.2,1)}
.exp-card:hover .exp-illus svg{transform:scale(1.1) rotate(-2deg)}
.exp-num{
  position:absolute;top:14px;right:16px;font-family:var(--font-mono);font-size:11px;color:var(--dim);letter-spacing:.15em;
}
.exp-body{padding:22px 24px 24px;display:flex;flex-direction:column;gap:10px;flex:1}
.exp-name{font-size:20px;font-weight:700;letter-spacing:.02em}
.exp-name-en{font-family:var(--font-mono);font-size:11px;color:var(--dim);letter-spacing:.18em;text-transform:uppercase;margin-top:-6px}
.exp-desc{font-size:13.5px;color:var(--muted);flex:1}
.exp-foot{display:flex;align-items:center;justify-content:space-between;margin-top:8px}
.exp-open{
  font-family:var(--font-mono);font-size:12px;letter-spacing:.1em;color:var(--cyan);
  display:inline-flex;align-items:center;gap:8px;
}
.che .exp-open{color:var(--amber)}
.exp-open svg{transition:transform .3s}
.exp-card:hover .exp-open svg{transform:translateX(5px)}

/* feature band */
.feat-band{
  margin-top:110px;border:1px solid var(--line);border-radius:22px;overflow:hidden;
  background:linear-gradient(140deg,#0c1826,#0a1322 60%,#121b10);
  display:grid;grid-template-columns:repeat(4,1fr);
}
.feat{padding:34px 28px;border-right:1px solid var(--line);position:relative;transition:background .3s}
.feat:last-child{border-right:none}
.feat:hover{background:rgba(255,255,255,.025)}
.feat .f-ico{
  width:46px;height:46px;border-radius:12px;display:grid;place-items:center;margin-bottom:18px;
  border:1px solid var(--line2);background:rgba(255,255,255,.03);
}
.feat h3{font-size:17px;margin-bottom:8px}
.feat p{font-size:13px;color:var(--muted)}

/* download */
.dl-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:22px}
.dl-card{
  border:1px solid var(--line);border-radius:18px;padding:32px 28px;position:relative;overflow:hidden;
  background:linear-gradient(165deg,var(--panel),var(--bg2));transition:.35s;
}
.dl-card:hover{border-color:var(--line2);transform:translateY(-6px)}
.dl-card .plat{font-family:var(--font-mono);font-size:11px;letter-spacing:.25em;color:var(--dim);text-transform:uppercase}
.dl-card h3{font-family:var(--font-display);font-weight:400;font-size:30px;margin:10px 0 6px}
.dl-card .ver{font-family:var(--font-mono);font-size:12px;color:var(--cyan);margin-bottom:18px}
.dl-card p{font-size:13.5px;color:var(--muted);margin-bottom:24px;min-height:44px}
.dl-btn{width:100%;justify-content:center}
.dl-card .glow{position:absolute;width:220px;height:220px;border-radius:50%;filter:blur(70px);opacity:.16;top:-90px;right:-70px;pointer-events:none}

/* footer */
.footer{margin-top:120px;border-top:1px solid var(--line);padding:44px 0 54px;background:var(--bg2)}
.footer-in{display:flex;justify-content:space-between;align-items:center;gap:24px;flex-wrap:wrap}
.footer .f-note{font-size:13px;color:var(--dim)}
.footer .f-links{display:flex;gap:22px;font-size:13px;color:var(--muted)}
.footer .f-links a:hover{color:var(--cyan)}

/* reveal animation */
.rv{opacity:0;transform:translateY(28px);transition:opacity .7s ease,transform .7s cubic-bezier(.2,.8,.2,1)}
.rv.on{opacity:1;transform:none}
.rv-d1{transition-delay:.08s}.rv-d2{transition-delay:.16s}.rv-d3{transition-delay:.24s}

/* ============================================================
   LAB SHELL (experiment pages)
   ============================================================ */
.lab-top{padding:96px 0 0}
.lab-crumb{display:flex;align-items:center;gap:10px;font-family:var(--font-mono);font-size:12px;color:var(--dim);letter-spacing:.1em}
.lab-crumb a{color:var(--muted)}
.lab-crumb a:hover{color:var(--cyan)}
.lab-title-row{display:flex;align-items:flex-end;justify-content:space-between;gap:20px;margin:16px 0 26px;flex-wrap:wrap}
.lab-title-row h1{font-family:var(--font-display);font-weight:400;font-size:clamp(30px,3.6vw,46px)}
.lab-title-row .sub{color:var(--muted);font-size:14px;max-width:560px}
.lab-wrap{
  display:grid;grid-template-columns:1fr 348px;gap:20px;align-items:start;margin-bottom:80px;
}
.stage{
  position:relative;border:1px solid var(--line);border-radius:18px;overflow:hidden;
  background:radial-gradient(ellipse 130% 110% at 50% -10%,#0e1b2c,#080f1a 70%);
  min-height:560px;box-shadow:inset 0 1px 0 rgba(255,255,255,.05),0 24px 60px rgba(0,0,0,.4);
}
.stage canvas{position:absolute;inset:0;width:100%;height:100%;touch-action:none}
.stage-hud{
  position:absolute;top:14px;left:14px;display:flex;gap:8px;z-index:5;flex-wrap:wrap;
}
.hud-chip{
  font-family:var(--font-mono);font-size:11px;letter-spacing:.12em;color:var(--muted);
  background:rgba(7,13,22,.72);border:1px solid var(--line);border-radius:8px;padding:6px 12px;
  backdrop-filter:blur(6px);
}
.hud-chip b{color:var(--cyan);font-weight:600}
.stage-tip{
  position:absolute;bottom:14px;left:50%;transform:translateX(-50%);z-index:5;
  font-size:12px;color:var(--dim);background:rgba(7,13,22,.72);border:1px solid var(--line);
  padding:6px 16px;border-radius:99px;backdrop-filter:blur(6px);white-space:nowrap;
  transition:opacity .5s;
}
/* control panel */
.panel{
  border:1px solid var(--line);border-radius:18px;background:linear-gradient(175deg,var(--panel),var(--bg2));
  padding:22px;display:flex;flex-direction:column;gap:18px;position:sticky;top:86px;
  max-height:calc(100vh - 110px);overflow-y:auto;
}
.panel-sec{border-bottom:1px dashed var(--line);padding-bottom:16px}
.panel-sec:last-child{border-bottom:none;padding-bottom:0}
.panel-sec>h4{
  font-family:var(--font-mono);font-size:11px;letter-spacing:.22em;color:var(--dim);
  text-transform:uppercase;margin-bottom:14px;display:flex;align-items:center;gap:8px;
}
.panel-sec>h4::before{content:"";width:8px;height:8px;border-radius:2px;background:var(--cyan);box-shadow:0 0 8px var(--cyan)}
.panel.che-panel .panel-sec>h4::before{background:var(--amber);box-shadow:0 0 8px var(--amber)}
.ctrl{margin-bottom:14px}
.ctrl:last-child{margin-bottom:0}
.ctrl-lab{display:flex;justify-content:space-between;font-size:13px;color:var(--muted);margin-bottom:8px}
.ctrl-lab .val{font-family:var(--font-mono);color:var(--cyan);font-size:13px}
.che-panel .ctrl-lab .val{color:var(--amber)}
input[type=range]{
  -webkit-appearance:none;appearance:none;width:100%;height:26px;background:transparent;
}
input[type=range]::-webkit-slider-runnable-track{
  height:4px;border-radius:2px;background:linear-gradient(90deg,var(--cyan) var(--p,50%),var(--line) var(--p,50%));
}
.che-panel input[type=range]::-webkit-slider-runnable-track{
  background:linear-gradient(90deg,var(--amber) var(--p,50%),var(--line) var(--p,50%));
}
input[type=range]::-webkit-slider-thumb{
  -webkit-appearance:none;width:18px;height:18px;border-radius:50%;margin-top:-7px;
  background:var(--ink);border:3px solid var(--cyan);box-shadow:0 0 10px color-mix(in srgb,var(--cyan) 60%,transparent);
  cursor:grab;transition:transform .15s;
}
.che-panel input[type=range]::-webkit-slider-thumb{border-color:var(--amber);box-shadow:0 0 10px color-mix(in srgb,var(--amber) 60%,transparent)}
input[type=range]::-webkit-slider-thumb:hover{transform:scale(1.15)}
input[type=range]::-moz-range-track{height:4px;border-radius:2px;background:var(--line)}
input[type=range]::-moz-range-progress{height:4px;border-radius:2px;background:var(--cyan)}
input[type=range]::-moz-range-thumb{width:14px;height:14px;border-radius:50%;background:var(--ink);border:3px solid var(--cyan);cursor:grab}
.seg{display:flex;background:var(--bg);border:1px solid var(--line);border-radius:10px;padding:4px;gap:4px}
.seg button{
  flex:1;font-size:13px;padding:8px 6px;border-radius:7px;color:var(--muted);transition:.2s;font-weight:500;
}
.seg button.on{background:color-mix(in srgb,var(--cyan) 16%,transparent);color:var(--cyan);box-shadow:inset 0 0 0 1px color-mix(in srgb,var(--cyan) 40%,transparent)}
.che-panel .seg button.on{background:color-mix(in srgb,var(--amber) 16%,transparent);color:var(--amber);box-shadow:inset 0 0 0 1px color-mix(in srgb,var(--amber) 40%,transparent)}
.btn-row{display:flex;gap:10px}
.btn-sm{
  flex:1;display:inline-flex;align-items:center;justify-content:center;gap:8px;
  font-size:13.5px;font-weight:600;padding:11px 10px;border-radius:10px;transition:.2s;
  border:1px solid var(--line2);color:var(--ink);background:rgba(255,255,255,.03);
}
.btn-sm:hover{border-color:var(--cyan);color:var(--cyan)}
.che-panel .btn-sm:hover{border-color:var(--amber);color:var(--amber)}
.btn-sm.primary{background:linear-gradient(120deg,var(--cyan),#2bd4ec);color:#052a24;border:none}
.btn-sm.primary:hover{color:#052a24;filter:brightness(1.1)}
.che-panel .btn-sm.primary{background:linear-gradient(120deg,var(--amber),var(--amber2));color:#3a1c02}
.che-panel .btn-sm.primary:hover{color:#3a1c02}
.btn-sm.warn:hover{border-color:var(--red);color:var(--red)}
.btn-sm:disabled{opacity:.4;cursor:not-allowed;transform:none}
/* readouts */
.ro-grid{display:grid;grid-template-columns:1fr 1fr;gap:10px}
.ro{
  border:1px solid var(--line);border-radius:11px;padding:10px 13px;background:rgba(255,255,255,.02);
}
.ro .k{font-size:10.5px;color:var(--dim);letter-spacing:.08em;font-family:var(--font-mono)}
.ro .v{font-family:var(--font-mono);font-size:19px;color:var(--cyan);margin-top:2px;line-height:1.2}
.che-panel .ro .v{color:var(--amber)}
.ro .v small{font-size:11px;color:var(--dim)}
/* data table */
.data-table{width:100%;border-collapse:collapse;font-size:12.5px}
.data-table th{
  font-family:var(--font-mono);font-size:10px;letter-spacing:.1em;color:var(--dim);
  text-align:left;padding:7px 8px;border-bottom:1px solid var(--line2);font-weight:500;
}
sub{font-size:.72em;line-height:0}
.data-table td{padding:7px 8px;border-bottom:1px solid var(--line);font-family:var(--font-mono);color:var(--muted)}
.data-table tr:last-child td{border-bottom:none}
.data-table td:first-child{color:var(--dim)}
.empty-row td{color:var(--dim)!important;text-align:center;font-family:var(--font-body)!important;font-size:12px;padding:14px 8px!important}
/* theory box */
.theory{font-size:13px;color:var(--muted);line-height:1.8}
.theory b{color:var(--ink)}
.theory .formula{
  display:block;text-align:center;font-family:var(--font-mono);color:var(--cyan);
  background:rgba(255,255,255,.03);border:1px solid var(--line);border-radius:9px;
  padding:10px;margin:10px 0;font-size:14px;letter-spacing:.05em;
}
.che-panel .theory .formula{color:var(--amber)}
details.theory-box summary{
  list-style:none;display:flex;align-items:center;justify-content:space-between;cursor:pointer;
  font-size:13.5px;font-weight:600;color:var(--ink);
}
details.theory-box summary::-webkit-details-marker{display:none}
details.theory-box summary .chev{transition:transform .3s;color:var(--dim)}
details.theory-box[open] summary .chev{transform:rotate(180deg)}
details.theory-box .theory{margin-top:12px}
/* toast */
.toast{
  position:fixed;bottom:28px;left:50%;transform:translate(-50%,80px);z-index:200;
  background:var(--panel2);border:1px solid var(--line2);color:var(--ink);
  padding:12px 24px;border-radius:12px;font-size:14px;opacity:0;transition:.4s cubic-bezier(.2,.8,.2,1);
  box-shadow:0 16px 40px rgba(0,0,0,.5);pointer-events:none;max-width:86vw;text-align:center;
}
.toast.show{opacity:1;transform:translate(-50%,0)}
.toast.ok{border-color:var(--cyan);color:var(--cyan)}
.toast.warn{border-color:var(--amber);color:var(--amber)}

/* ---------- download page ---------- */
.dl-hero{padding:150px 0 60px;text-align:center}
.dl-hero h1{font-family:var(--font-display);font-weight:400;font-size:clamp(38px,5vw,64px)}
.dl-hero p{color:var(--muted);margin:18px auto 0;max-width:520px}
.qr-note{margin-top:70px;border:1px dashed var(--line2);border-radius:16px;padding:28px;text-align:center;color:var(--muted);font-size:13.5px}
.qr-note code{font-family:var(--font-mono);color:var(--cyan);background:rgba(255,255,255,.04);padding:2px 8px;border-radius:6px}

/* ---------- responsive ---------- */
@media (max-width:1080px){
  .hero-in{grid-template-columns:1fr;gap:40px}
  .hero-panel{max-width:560px}
  .exp-grid{grid-template-columns:repeat(2,1fr)}
  .feat-band{grid-template-columns:repeat(2,1fr)}
  .feat:nth-child(2n){border-right:none}
  .feat{border-bottom:1px solid var(--line)}
  .lab-wrap{grid-template-columns:1fr}
  .panel{position:static;max-height:none}
  .stage{min-height:480px}
}
@media (max-width:680px){
  .nav-links{
    position:fixed;top:68px;right:0;left:0;flex-direction:column;align-items:stretch;
    background:var(--bg2);border-bottom:1px solid var(--line);padding:14px 4vw 20px;gap:4px;
    transform:translateY(-130%);transition:transform .35s;box-shadow:0 30px 40px rgba(0,0,0,.5);
  }
  .nav-links.open{transform:none}
  .nav-burger{display:flex}
  .exp-grid,.dl-grid{grid-template-columns:1fr}
  .stat-strip{flex-direction:column}
  .stat{border-right:none;border-bottom:1px solid var(--line)}
  .stat:last-child{border-bottom:none}
  .stage{min-height:400px}
  .hero{padding-top:120px}
}
@media (max-width:480px){
  .feat-band{grid-template-columns:1fr}
  .feat{border-right:none}
}