:root{
  --bg:#0b1220;
  --card:#0f1b33;
  --card2:#0d1730;
  --text:#e7eefc;
  --muted:#a7b6d8;
  --brand:#3b82f6;
  --brand2:#22c55e;
  --border:rgba(231,238,252,0.12);
  --shadow: 0 12px 30px rgba(0,0,0,.35);
}
*{box-sizing:border-box}
html,body{height:100%}
body{
  margin:0;
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, "Apple Color Emoji","Segoe UI Emoji";
  background: radial-gradient(1200px 700px at 20% 10%, rgba(59,130,246,.25), transparent 60%),
              radial-gradient(900px 600px at 80% 20%, rgba(34,197,94,.15), transparent 55%),
              linear-gradient(180deg, var(--bg), #070c16);
  color:var(--text);
  line-height:1.5;
}
a{color:inherit}
.container{max-width:1100px;margin:0 auto;padding:0 20px}

/* Header */
.header{
  position:sticky;top:0;z-index:20;
  backdrop-filter: blur(10px);
  background: rgba(7,12,22,.65);
  border-bottom:1px solid var(--border);
}
.header-inner{display:flex;align-items:center;justify-content:space-between;gap:14px;padding:14px 0}
.brand{display:flex;align-items:center;gap:12px;text-decoration:none}
.logo{
  width:38px;height:38px;border-radius:12px;
  background: linear-gradient(135deg, rgba(59,130,246,.9), rgba(34,197,94,.85));
  box-shadow: 0 10px 20px rgba(59,130,246,.18);
  display:grid;place-items:center;
  font-weight:800;
  letter-spacing:.5px;
}
.brand-name{font-weight:800;letter-spacing:.2px}
.nav{display:flex;align-items:center;gap:10px;flex-wrap:wrap;justify-content:flex-end}
.nav a{
  text-decoration:none;
  padding:8px 10px;
  border-radius:10px;
  color:var(--muted);
  border:1px solid transparent;
}
.nav a:hover{color:var(--text);border-color:var(--border);background:rgba(255,255,255,.03)}

/* Buttons */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:10px;
  border-radius:14px;
  padding:12px 16px;
  border:1px solid var(--border);
  text-decoration:none;
  font-weight:700;
  box-shadow:none;
}
.btn-primary{background:rgba(59,130,246,.95);border-color:rgba(59,130,246,.55)}
.btn-primary:hover{filter:brightness(1.03)}
.btn-ghost{background:rgba(255,255,255,.03)}
.btn-ghost:hover{background:rgba(255,255,255,.06)}
.badge{display:inline-flex;align-items:center;gap:8px;padding:6px 10px;border-radius:999px;border:1px solid var(--border);color:var(--muted);font-size:13px}

/* Hero */
.hero{padding:56px 0 20px}
.hero-grid{display:grid;grid-template-columns:1.3fr .7fr;gap:22px;align-items:stretch}
@media (max-width: 900px){.hero-grid{grid-template-columns:1fr;}}
.h1{font-size:44px;line-height:1.08;margin:14px 0 12px;letter-spacing:-.6px}
@media (max-width: 520px){.h1{font-size:36px}}
.sub{color:var(--muted);font-size:17px;margin:0 0 18px;max-width:62ch}
.cta{display:flex;gap:12px;flex-wrap:wrap;margin-top:12px}

.card{
  background: linear-gradient(180deg, rgba(255,255,255,.05), rgba(255,255,255,.02));
  border:1px solid var(--border);
  border-radius:18px;
  box-shadow: var(--shadow);
}
.card-pad{padding:18px}
.panel-title{font-weight:800;margin:0 0 8px}
.panel-sub{color:var(--muted);margin:0;font-size:14px}

.kpi{display:grid;grid-template-columns:1fr 1fr;gap:10px;margin-top:14px}
.kpi .mini{padding:12px;border-radius:14px;border:1px solid var(--border);background:rgba(15,27,51,.45)}
.mini b{display:block;font-size:14px}
.mini span{color:var(--muted);font-size:13px}

/* Sections */
.section{padding:28px 0}
.section h2{margin:0 0 10px;font-size:24px;letter-spacing:-.3px}
.section p{margin:0 0 12px;color:var(--muted)}
.grid3{display:grid;grid-template-columns:repeat(3,1fr);gap:14px}
@media (max-width: 900px){.grid3{grid-template-columns:1fr}}
.feature{padding:16px;border-radius:16px;border:1px solid var(--border);background:rgba(15,27,51,.45)}
.feature h3{margin:0 0 6px;font-size:16px}
.feature p{margin:0;color:var(--muted);font-size:14px}

/* Problem cards */
.problem-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:14px}
@media (max-width: 900px){.problem-grid{grid-template-columns:1fr}}
.problem{padding:16px;border-radius:18px;border:1px solid var(--border);background:rgba(15,27,51,.45)}
.problem h3{margin:0 0 8px}
.problem .hint{color:var(--muted);font-size:13px;margin:0 0 10px}
.list{margin:0;padding-left:18px;color:var(--muted)}
.list li{margin:6px 0}
.list a{color:var(--text)}
.note{color:var(--muted);font-size:13px}

/* Footer */
.footer{margin-top:34px;padding:26px 0;border-top:1px solid var(--border);color:var(--muted)}
.footer a{color:var(--muted)}
.footer a:hover{color:var(--text)}
.footer-grid{display:flex;gap:14px;justify-content:space-between;flex-wrap:wrap;align-items:flex-start}
.small{font-size:13px}

/* Content pages */
.page{padding:28px 0}
.prose{max-width:80ch}
.prose h1{margin:10px 0 10px;font-size:34px;letter-spacing:-.5px}
.prose h2{margin:22px 0 10px;font-size:20px}
.prose p{color:var(--muted);margin:0 0 12px}
.prose ul{color:var(--muted)}
hr{border:0;border-top:1px solid var(--border);margin:18px 0}
.code{font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace; font-size: 13px; color: var(--text); background: rgba(255,255,255,.04); border: 1px solid var(--border); padding: 10px 12px; border-radius: 14px; overflow:auto}

/* Utility */
.m0{margin:0}
.mt8{margin-top:8px}
.mt12{margin-top:12px}
.mt18{margin-top:18px}