/* Riverxo V6 — single menu, improved visual system */
:root{
  color-scheme: dark;
  --bg:#0b1118; --bg-2:#0d141c;
  --fg:#eaf4ff; --muted:#a7bccd;
  --accent:#00e7ff; --accent-2:#6d5aff;
  --card:#0f1722; --radius:18px;
  --ring:0 0 0 3px rgba(0,231,255,.25);
  --shadow:0 20px 70px rgba(0,0,0,.45);
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;font:16px/1.6 ui-sans-serif, -apple-system, Segoe UI, Inter, Roboto, Helvetica, Arial; color:var(--fg);
  background: radial-gradient(1000px 700px at 20% -10%, var(--bg-2) 0, var(--bg) 60%), var(--bg);
  -webkit-font-smoothing:antialiased; text-rendering:optimizeLegibility}
a{color:inherit; text-decoration:none}
a:focus-visible,button:focus-visible{outline:none; box-shadow:var(--ring)}
/* Buttons */
.btn{display:inline-flex; align-items:center; gap:.55rem; padding:.85rem 1.1rem; border-radius:14px; font-weight:700; transition:transform .08s ease, filter .2s}
.btn:active{transform:translateY(1px)}
.btn.primary{background:linear-gradient(135deg,var(--accent),var(--accent-2)); color:#001018}
.btn.ghost{border:1px solid rgba(255,255,255,.12); background:rgba(255,255,255,.04)}
/* Header — single row; mobile drawer only below 900px */
.header{position:sticky; top:0; z-index:50; background:rgba(10,15,20,.7); backdrop-filter: blur(10px);
  border-bottom:1px solid rgba(255,255,255,.06)}
.header-inner{max-width:1120px; margin:0 auto; padding:12px 18px; display:flex; align-items:center; justify-content:space-between; gap:12px}
.brand{display:flex; align-items:center; gap:12px; font-weight:800}
.brand img{width:28px;height:28px}
nav.main{display:flex; gap:10px; align-items:center}
#menuBtn{display:none}
#mobileMenu{display:none} /* ALWAYS hidden by default */
@media (max-width:900px){
  nav.main{display:none}
  #menuBtn{display:inline-flex}
  #mobileMenu{display:none; padding:10px 18px 16px}
  #mobileMenu.open{display:grid; gap:10px}
}
/* Layout */
.container{max-width:1120px; margin:0 auto; padding:0 18px}
.hero{display:grid; grid-template-columns:1.2fr .8fr; gap:28px; align-items:center; margin:62px auto 40px}
.card{background:linear-gradient(180deg,rgba(255,255,255,.05),transparent);
  border:1px solid rgba(255,255,255,.10); border-radius:var(--radius); padding:28px; box-shadow:var(--shadow)}
/* Gradient border accent on hero heading */
h1{font-size:clamp(36px,5vw,60px); line-height:1.1; margin:0 0 18px; letter-spacing:.2px}
h1::after{content:""; display:block; height:3px; width:84px; margin-top:14px;
  background:linear-gradient(90deg,var(--accent),var(--accent-2)); border-radius:3px; opacity:.9}
p.lead{font-size:clamp(18px,2.4vw,22px); color:var(--muted); margin:0 0 22px}
.grid{display:grid; gap:18px}
.grid.cols-3{grid-template-columns:repeat(3,1fr)}
.tile{background:var(--card); border:1px solid rgba(255,255,255,.08); border-radius:var(--radius); padding:22px; min-height:140px}
.tile h3{margin:0 0 8px; font-size:18px}
.tile p{margin:0; color:var(--muted)}
.footer{padding:34px 18px 60px; margin-top:30px; display:flex; justify-content:space-between; align-items:center; border-top:1px solid rgba(255,255,255,.06)}
.small{color:var(--muted); font-size:14px}
@media (max-width:900px){
  .hero{grid-template-columns:1fr}
  .grid.cols-3{grid-template-columns:1fr}
}