:root{
  --bg:#f6f7fb;
  --card:#ffffff;
  --text:#1f2937;
  --muted:#6b7280;
  --line:#e5e7eb;
  --accent:#2563eb;
  --accent2:#22c55e;
}

*{box-sizing:border-box}

body{
  margin:0;
  font-family: system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
  background:
    radial-gradient(1200px 800px at 10% -10%, rgba(37,99,235,.08), transparent 60%),
    radial-gradient(900px 600px at 90% 10%, rgba(34,197,94,.08), transparent 55%),
    var(--bg);
  color:var(--text);
}

a{color:inherit; text-decoration:none}

.container{
  max-width:1100px;
  margin:0 auto;
  padding:22px;
}

/* NAVBAR */
.nav{
  position:sticky;
  top:0;
  z-index:10;
  background: rgba(255,255,255,.8);
  backdrop-filter: blur(10px);
  border-bottom:1px solid var(--line);
}

.nav-inner{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:14px;
}

.brand{
  display:flex;
  align-items:center;
  gap:10px;
  font-weight:800;
}

.logo{
  width:34px;
  height:34px;
  border-radius:10px;
  background: linear-gradient(135deg, var(--accent), var(--accent2));
}

.menu{
  display:flex;
  flex-wrap:wrap;
  gap:6px;
}

.menu a{
  padding:8px 12px;
  border-radius:10px;
  color:var(--muted);
}

.menu a:hover{
  background:#eef2ff;
  color:var(--accent);
}

.menu a.active{
  background:#e0e7ff;
  color:var(--accent);
  font-weight:600;
}

/* HERO */
.hero{
  padding:36px 0 16px;
}

.hero h1{
  font-size: clamp(28px, 3.6vw, 44px);
  line-height:1.1;
  margin:0 0 12px;
}

.hero p{
  margin:0;
  color:var(--muted);
  max-width:70ch;
}

.badges{
  display:flex;
  flex-wrap:wrap;
  gap:10px;
  margin-top:16px;
}

.badge{
  font-size:13px;
  padding:8px 12px;
  border-radius:999px;
  background:#eef2ff;
  color:#1e40af;
}

/* GRID */
.grid{
  display:grid;
  grid-template-columns: repeat(12, 1fr);
  gap:16px;
  margin:22px 0 10px;
}

.card{
  grid-column: span 12;
  background: var(--card);
  border:1px solid var(--line);
  border-radius:16px;
  padding:18px;
}

@media(min-width:900px){
  .card.half{grid-column: span 6}
  .card.third{grid-column: span 4}
}

.section-title{
  display:flex;
  align-items:center;
  justify-content:space-between;
  margin-bottom:8px;
}

.section-title h2{
  margin:0;
  font-size:20px;
}

.section-title .hint{
  font-size:13px;
  color:var(--muted);
}

/* BUTTONS */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  padding:10px 14px;
  border-radius:12px;
  border:1px solid var(--line);
  background:#ffffff;
  gap:8px;
  cursor:pointer;
}

.btn:hover{
  background:#f1f5f9;
}

.btn.primary{
  background:var(--accent);
  color:#fff;
  border-color:var(--accent);
}

.btn.primary:hover{
  background:#1d4ed8;
}

/* VIDEOS */
.video-list{
  display:grid;
  grid-template-columns: repeat(12, 1fr);
  gap:14px;
}

.video-item{
  grid-column: span 12;
  display:flex;
  gap:14px;
  padding:12px;