:root {
  --bg: #0b1020;
  --bg-2: #10182f;
  --card: rgba(255,255,255,0.08);
  --card-border: rgba(255,255,255,0.12);
  --text: #f5f7fb;
  --muted: #b8c0d9;
  --accent: #6ea8fe;
  --accent-2: #8ef0c7;
  --shadow: 0 20px 60px rgba(0,0,0,0.35);
  --radius: 24px;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Arial, sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at top left, rgba(110,168,254,0.24), transparent 30%),
    radial-gradient(circle at top right, rgba(142,240,199,0.18), transparent 25%),
    linear-gradient(180deg, var(--bg) 0%, var(--bg-2) 100%);
}

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

.container {
  width: min(1120px, calc(100% - 28px));
  margin: 0 auto;
}

.home-hero {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 24px 0 40px;
}

.brand {
  display: inline-flex;
  align-items: center;
  width: fit-content;
  gap: 10px;
  padding: 10px 14px;
  border-radius: 999px;
  background: rgba(255,255,255,0.08);
  border: 1px solid rgba(255,255,255,0.12);
  font-weight: 800;
  font-size: 14px;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  margin-bottom: 14px;
}

.home-hero h1 {
  margin: 0 0 10px;
  font-size: clamp(30px, 5vw, 54px);
  line-height: 1.04;
  max-width: 800px;
}

.home-hero p {
  margin: 0 0 24px;
  color: var(--muted);
  font-size: 17px;
  line-height: 1.6;
  max-width: 760px;
}

.home-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
}

.platform-card {
  display: block;
  padding: 24px;
  border-radius: 26px;
  background: rgba(255,255,255,0.08);
  border: 1px solid rgba(255,255,255,0.12);
  box-shadow: var(--shadow);
  transition: transform 0.18s ease, border-color 0.18s ease, background 0.18s ease;
}

.platform-card:hover {
  transform: translateY(-2px);
  border-color: rgba(110,168,254,0.42);
  background: rgba(255,255,255,0.10);
}

.platform-badge {
  display: inline-flex;
  align-items: center;
  min-height: 32px;
  padding: 0 12px;
  border-radius: 999px;
  background: rgba(110,168,254,0.14);
  border: 1px solid rgba(110,168,254,0.28);
  color: #dbe9ff;
  font-size: 13px;
  font-weight: 800;
  margin-bottom: 14px;
}

.platform-card h2 {
  margin: 0 0 8px;
  font-size: 26px;
}

.platform-card p {
  margin: 0 0 16px;
  color: var(--muted);
  line-height: 1.6;
}

.platform-link {
  font-weight: 800;
  color: #dfe9ff;
}

.topbar {
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(12px);
  background: rgba(11,16,32,0.72);
  border-bottom: 1px solid rgba(255,255,255,0.08);
}

.topbar-inner {
  width: min(1120px, calc(100% - 28px));
  margin: 0 auto;
  min-height: 74px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
}

.topbar-title {
  font-weight: 800;
  font-size: 20px;
  white-space: nowrap;
}

.topbar-actions {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  justify-content: flex-end;
}

.btn {
  display: inline-flex;
  justify-content: center;
  align-items: center;
  min-height: 48px;
  padding: 0 16px;
  border-radius: 14px;
  font-weight: 800;
  border: 1px solid transparent;
  transition: transform 0.18s ease, opacity 0.18s ease;
}

.btn:hover {
  transform: translateY(-1px);
  opacity: 0.96;
}

.btn-primary {
  background: linear-gradient(135deg, var(--accent), #4f7cff);
  color: #fff;
  box-shadow: 0 10px 26px rgba(79,124,255,0.35);
}

.btn-secondary {
  background: rgba(255,255,255,0.06);
  color: var(--text);
  border-color: rgba(255,255,255,0.12);
}

.page-offset {
  padding-top: 22px;
  padding-bottom: 36px;
}

.instruction-card {
  background: var(--card);
  border: 1px solid var(--card-border);
  border-radius: 26px;
  box-shadow: var(--shadow);
  padding: 22px;
}

.instruction-badge {
  display: inline-flex;
  align-items: center;
  min-height: 32px;
  padding: 0 12px;
  border-radius: 999px;
  background: rgba(142,240,199,0.12);
  border: 1px solid rgba(142,240,199,0.22);
  font-size: 13px;
  font-weight: 800;
  margin-bottom: 14px;
}

.instruction-card h1 {
  margin: 0 0 10px;
  font-size: clamp(28px, 4vw, 42px);
  line-height: 1.06;
}

.instruction-card p {
  margin: 0 0 18px;
  color: var(--muted);
  line-height: 1.6;
}

.steps {
  margin: 0 0 22px;
  padding-left: 20px;
  line-height: 1.7;
}

.steps li + li {
  margin-top: 8px;
}

.video-block + .video-block {
  margin-top: 16px;
}

.video-title {
  margin-bottom: 10px;
  font-size: 15px;
  font-weight: 800;
}

.video {
  width: 100%;
  max-width: 420px;
  aspect-ratio: 9 / 16;
  border-radius: 18px;
  background: #000;
  display: block;
}

.video-path {
  margin-top: 8px;
  font-size: 13px;
  color: var(--muted);
  word-break: break-all;
}

.back-link {
  display: inline-block;
  margin-top: 18px;
  color: #dfe9ff;
  font-weight: 700;
}

@media (max-width: 860px) {
  .home-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 640px) {
  .topbar-inner {
    align-items: stretch;
    padding: 10px 0;
    flex-direction: column;
  }

  .topbar-title {
    width: 100%;
  }

  .topbar-actions {
    width: 100%;
    display: grid;
    grid-template-columns: 1fr 1fr;
  }

  .btn {
    width: 100%;
  }

  .container,
  .topbar-inner {
    width: min(100% - 18px, 1120px);
  }

  .platform-card,
  .instruction-card {
    padding: 18px;
  }

  .video {
    max-width: 100%;
  }
}