/* =========================================================
   TRAINING — shared design system
   Opera GX aesthetic. Dark, neon red accent, gaming feel.
   ========================================================= */

@import url('https://fonts.googleapis.com/css2?family=Orbitron:wght@500;700;900&family=Inter:wght@400;500;600;700&family=JetBrains+Mono:wght@500&display=swap');

:root {
  --bg: #07070b;
  --surface: #12121a;
  --surface-2: #1a1a26;
  --border: #2a2a3a;
  --border-bright: #3a3a4f;
  --accent: #ff3656;
  --accent-bright: #ff5073;
  --accent-dim: #b8243e;
  --accent-glow: rgba(255, 54, 86, 0.35);
  --accent-glow-soft: rgba(255, 54, 86, 0.12);
  --cyan: #33d8ff;
  --text: rgba(255, 255, 255, 0.94);
  --text-muted: rgba(255, 255, 255, 0.58);
  --text-dim: rgba(255, 255, 255, 0.38);
  --font-display: 'Orbitron', system-ui, sans-serif;
  --font-body: 'Inter', system-ui, sans-serif;
  --font-mono: 'JetBrains Mono', ui-monospace, monospace;
  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --shadow-glow: 0 0 40px -10px var(--accent-glow);
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html, body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.55;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
  /* clip instead of hidden — hidden creates a scroll container
     on body and breaks position: sticky on descendants */
  overflow-x: clip;
}

/* subtle grain overlay across everything */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 1;
  background-image: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='160' height='160'><filter id='n'><feTurbulence baseFrequency='0.9' numOctaves='2' stitchTiles='stitch'/></filter><rect width='160' height='160' filter='url(%23n)' opacity='0.04'/></svg>");
  mix-blend-mode: overlay;
}

/* background radial pulse behind everything */
body::after {
  content: "";
  position: fixed;
  top: -30vh; left: -20vw;
  width: 80vw; height: 80vh;
  background: radial-gradient(circle, var(--accent-glow-soft) 0%, transparent 65%);
  pointer-events: none; z-index: 0;
}

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

/* =========================================================
   LAYOUT: left island sidebar + right content
   ========================================================= */
.layout {
  display: grid;
  grid-template-columns: 260px 1fr;
  gap: 20px;
  padding: 20px;
  min-height: 100vh;
  position: relative;
  z-index: 2;
}

/* sidebar column — sticky, viewport-tall, centers the sidebar card vertically.
   Default grid `align-items: stretch` makes the cell fill the row, which gives
   sticky room to slide as the user scrolls past 100vh of content. */
.sidebar-col {
  position: sticky;
  top: 0;
  align-self: stretch;
  height: 100vh;
  display: flex;
  align-items: center;
  padding: 20px 0;
}

.sidebar {
  width: 100%;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 18px 16px;
  display: flex;
  flex-direction: column;
  gap: 14px;
  max-height: calc(100vh - 40px);
  overflow-y: auto;
  box-shadow:
    0 0 0 1px rgba(255,255,255,0.02) inset,
    0 24px 60px -20px rgba(0,0,0,0.6),
    0 0 80px -20px var(--accent-glow-soft);
}

.sidebar::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: var(--radius-lg);
  padding: 1px;
  background: linear-gradient(180deg, var(--accent-glow) 0%, transparent 30%, transparent 70%, var(--accent-glow-soft) 100%);
  -webkit-mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  pointer-events: none;
  opacity: 0.5;
}

.logo {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 26px;
  letter-spacing: 0.15em;
  background: linear-gradient(135deg, #fff 0%, var(--accent-bright) 60%, var(--accent) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  text-shadow: 0 0 28px var(--accent-glow);
  padding-left: 4px;
  user-select: none;
}

.logo-sub {
  font-family: var(--font-mono);
  font-size: 10px;
  color: var(--text-dim);
  letter-spacing: 0.2em;
  padding-left: 4px;
  margin-top: 4px;
  text-transform: uppercase;
}

.nav { list-style: none; display: flex; flex-direction: column; gap: 4px; }

.nav-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  color: var(--text-muted);
  font-weight: 500;
  font-size: 13.5px;
  transition: background 150ms ease, color 150ms ease;
  cursor: pointer;
  border: 1px solid transparent;
}
.nav-item:hover { color: var(--text); background: var(--surface-2); }
.nav-item.active {
  color: var(--text);
  background: linear-gradient(90deg, var(--accent-glow-soft) 0%, transparent 60%);
  border-color: var(--accent-dim);
  box-shadow: inset 3px 0 0 var(--accent);
}
.nav-item svg { width: 18px; height: 18px; flex: 0 0 18px; }

.nav-section {
  font-family: var(--font-mono);
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 0.2em;
  color: var(--text-dim);
  padding: 4px 12px 2px;
  margin-top: 2px;
}

.sidebar-foot {
  margin-top: 4px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-size: 12px;
  color: var(--text-dim);
}

.foot-links {
  display: flex;
  gap: 8px;
}
.foot-links a {
  padding: 8px 10px;
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 12px;
  color: var(--text-muted);
  transition: all 150ms ease;
  flex: 1;
  text-align: center;
}
.foot-links a:hover {
  border-color: var(--accent);
  color: var(--text);
  box-shadow: 0 0 16px -4px var(--accent-glow);
}

/* =========================================================
   MAIN CONTENT
   ========================================================= */
.main {
  padding: 8px 8px 60px 8px;
  max-width: 1100px;
}

.hero {
  padding: 80px 0 60px;
  position: relative;
}

.hero h1 {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(44px, 6vw, 78px);
  line-height: 1.0;
  letter-spacing: -0.01em;
  margin-bottom: 24px;
}
.hero h1 .accent {
  background: linear-gradient(135deg, var(--accent) 0%, var(--accent-bright) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  text-shadow: 0 0 32px var(--accent-glow);
}

.hero .kicker {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--accent);
  padding: 6px 12px;
  background: var(--accent-glow-soft);
  border: 1px solid var(--accent-dim);
  border-radius: 999px;
  margin-bottom: 24px;
}

.hero p.lede {
  font-size: 20px;
  color: var(--text-muted);
  max-width: 720px;
  margin-bottom: 40px;
}

.cta-row { display: flex; gap: 12px; flex-wrap: wrap; }

.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 14px 24px;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-family: var(--font-body);
  font-size: 15px;
  cursor: pointer;
  transition: transform 120ms ease, box-shadow 200ms ease, background 200ms ease;
  border: 1px solid transparent;
  text-decoration: none;
  letter-spacing: 0.01em;
}
.btn-primary {
  background: linear-gradient(135deg, var(--accent) 0%, var(--accent-bright) 100%);
  color: #fff;
  box-shadow: 0 0 32px -8px var(--accent-glow), inset 0 1px 0 rgba(255,255,255,0.2);
}
.btn-primary:hover {
  transform: translateY(-1px);
  box-shadow: 0 0 48px -6px var(--accent-glow), inset 0 1px 0 rgba(255,255,255,0.25);
}
.btn-secondary {
  background: var(--surface);
  color: var(--text);
  border-color: var(--border-bright);
}
.btn-secondary:hover {
  border-color: var(--accent);
  color: var(--text);
}
.btn svg { width: 18px; height: 18px; }

/* =========================================================
   SECTION BLOCKS
   ========================================================= */
section.block {
  padding: 56px 0;
  border-top: 1px solid var(--border);
}
section.block:first-of-type { border-top: 0; }

.section-label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.25em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 12px;
}
.section-title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(28px, 3.5vw, 44px);
  margin-bottom: 20px;
  letter-spacing: -0.01em;
}
.section-body {
  font-size: 16px;
  color: var(--text-muted);
  max-width: 800px;
}
.section-body p + p { margin-top: 16px; }
.section-body strong { color: var(--text); font-weight: 600; }

/* card grid for scenarios, etc */
.grid-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
  margin-top: 32px;
}
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 24px;
  transition: transform 160ms ease, border-color 160ms ease, box-shadow 200ms ease;
  position: relative;
  overflow: hidden;
}
.card:hover {
  transform: translateY(-2px);
  border-color: var(--border-bright);
  box-shadow: 0 16px 32px -12px rgba(0,0,0,0.5), 0 0 60px -30px var(--accent-glow);
}
.card .card-num {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--accent);
  letter-spacing: 0.2em;
  margin-bottom: 10px;
}
.card h3 {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 18px;
  letter-spacing: 0.02em;
  margin-bottom: 10px;
}
.card p { color: var(--text-muted); font-size: 14px; }

/* stats row */
.stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 16px;
  margin-top: 32px;
}
.stat {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 20px;
}
.stat .n {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 36px;
  color: var(--accent);
  line-height: 1;
  margin-bottom: 8px;
}
.stat .l {
  font-size: 13px;
  color: var(--text-muted);
  letter-spacing: 0.05em;
}

/* footer */
.site-footer {
  padding: 40px 0 0;
  border-top: 1px solid var(--border);
  color: var(--text-dim);
  font-size: 13px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
}

/* =========================================================
   Responsive
   ========================================================= */
@media (max-width: 860px) {
  .layout { grid-template-columns: 1fr; padding: 12px; }
  .sidebar-col { position: static; height: auto; padding: 0; display: block; }
  .sidebar { max-height: none; overflow: visible; flex-direction: row; align-items: center; flex-wrap: wrap; }
  .nav { flex-direction: row; flex-wrap: wrap; flex: 1; justify-content: flex-end; gap: 4px; }
  .nav-section, .logo-sub, .sidebar-foot { display: none; }
  .main { padding: 8px 0 40px; }
}