/* AI Training Collab — Day26 overview
   Standing nvai.dev design system: dark default, purple/gold, Quicksand + Inter. */

:root {
  --radius: 1.15rem;
  --radius-sm: .75rem;
  --bg: #0A0712;
  --surface: #141021;
  --surface-2: #1B1529;
  --border: rgba(255,255,255,.08);
  --text: #F2EFF8;
  --muted: #A9A3B8;
  --purple: #9B86D6;
  --purple-strong: #7B68AE;
  --gold: #E0BE5C;
  --gold-strong: #D4AF37;
  --live: #4ADE80;
  --live-bg: rgba(74,222,128,.12);
  --gold-bg: rgba(212,175,55,.12);
  --blue: #38BDF8;
  --shadow: 0 24px 60px rgba(0,0,0,.55);
  --glow:
    radial-gradient(60rem 36rem at 10% -10%, rgba(139,119,201,.20), transparent 62%),
    radial-gradient(48rem 30rem at 100% 110%, rgba(212,175,55,.10), transparent 60%);
}
[data-theme="light"] {
  --bg: #FAF8F5;
  --surface: #FFFFFF;
  --surface-2: #F6F2FA;
  --border: #EAE4F2;
  --text: #1A0A2E;
  --muted: #5B5566;
  --purple: #7B68AE;
  --purple-strong: #6A57A0;
  --gold: #B8912B;
  --gold-strong: #A8842A;
  --live: #16A34A;
  --live-bg: rgba(22,163,74,.10);
  --gold-bg: rgba(184,145,43,.12);
  --blue: #0284C7;
  --shadow: 0 20px 50px rgba(26,10,46,.10);
  --glow:
    radial-gradient(60rem 36rem at 10% -10%, rgba(123,104,174,.14), transparent 62%),
    radial-gradient(48rem 30rem at 100% 110%, rgba(212,175,55,.16), transparent 60%);
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; color-scheme: dark; scroll-behavior: smooth; }
[data-theme="light"] { color-scheme: light; }
body {
  margin: 0;
  min-height: 100vh;
  font-family: 'Inter', system-ui, -apple-system, 'Segoe UI', sans-serif;
  font-size: 1rem;
  line-height: 1.6;
  color: var(--text);
  background-color: var(--bg);
  background-image: var(--glow);
  -webkit-font-smoothing: antialiased;
  transition: background-color .3s ease, color .3s ease;
}
::selection { background: rgba(139,119,201,.35); }
a { color: inherit; }
a:focus-visible, button:focus-visible {
  outline: 2px solid var(--purple); outline-offset: 2px;
}

.container { width: 100%; max-width: 72rem; margin: 0 auto; padding: 0 1.5rem; }

/* ---------- Topbar ---------- */
.topbar { border-bottom: 1px solid var(--border); }
.topbar-inner {
  display: flex; align-items: center; justify-content: space-between;
  gap: 1rem; padding-top: 1.1rem; padding-bottom: 1.1rem;
}
.brand {
  display: inline-flex; align-items: center; gap: .6rem;
  font-family: 'Quicksand', sans-serif; font-weight: 700;
  font-size: 1.12rem; letter-spacing: -.01em;
  color: var(--text); text-decoration: none;
}
.brand-mark {
  width: 1.05rem; height: 1.05rem; border-radius: 50%;
  background: linear-gradient(135deg, var(--purple-strong), var(--gold-strong));
  box-shadow: 0 0 0 3px rgba(123,104,174,.18);
}
.topbar-right { display: flex; align-items: center; gap: .75rem; }
.topnav { display: flex; align-items: center; gap: .25rem; }
.topnav a {
  font-family: 'Quicksand', sans-serif; font-weight: 600; font-size: .9rem;
  color: var(--muted); text-decoration: none;
  padding: .42rem .7rem; border-radius: 999px;
  transition: color .15s ease, background-color .15s ease;
}
.topnav a:hover { color: var(--text); background: var(--surface-2); }

.theme-toggle {
  display: inline-flex; align-items: center; justify-content: center;
  width: 2.25rem; height: 2.25rem; border-radius: 999px;
  border: 1px solid var(--border); background: var(--surface);
  color: var(--text); font-size: 1rem; line-height: 1; cursor: pointer;
  transition: border-color .15s ease, transform .15s ease;
}
.theme-toggle:hover { border-color: var(--purple); transform: translateY(-1px); }

/* ---------- Hero ---------- */
.hero { padding: 3.5rem 0 1.5rem; }
.eyebrow {
  display: inline-flex; align-items: center; gap: .5rem;
  font-family: 'Quicksand', sans-serif; font-weight: 600;
  font-size: .78rem; letter-spacing: .16em; text-transform: uppercase;
  color: var(--purple);
}
.eyebrow .dot { width: .45rem; height: .45rem; border-radius: 50%; background: var(--gold-strong); }
h1 {
  font-family: 'Quicksand', sans-serif; font-weight: 700;
  font-size: clamp(2.4rem, 5.5vw, 3.6rem);
  line-height: 1.05; letter-spacing: -.025em;
  margin: .9rem 0 1rem;
}
.grad {
  background: linear-gradient(120deg, var(--purple), var(--gold));
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent; color: transparent;
}
.lede {
  max-width: 46rem; margin: 0 0 1.75rem;
  font-size: 1.08rem; color: var(--muted);
}
.lede strong { color: var(--text); font-weight: 600; }
.hero-actions { display: flex; flex-wrap: wrap; gap: .75rem; margin-bottom: 2.25rem; }

.btn {
  display: inline-flex; align-items: center; gap: .5rem;
  font-family: 'Quicksand', sans-serif; font-weight: 600; font-size: .95rem;
  padding: .72rem 1.2rem; border-radius: 999px; text-decoration: none;
  border: 1px solid var(--border); background: var(--surface); color: var(--text);
  transition: transform .15s ease, border-color .15s ease, background-color .15s ease;
}
.btn:hover { transform: translateY(-1px); border-color: var(--purple); }
.btn-primary {
  background: linear-gradient(135deg, var(--gold-strong), #E8CD7A);
  border-color: transparent; color: #1A0A2E;
}
.btn-primary:hover { border-color: transparent; filter: brightness(1.05); }

/* ---------- Metadata rows ---------- */
.meta-rows {
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  display: grid; grid-template-columns: repeat(4, minmax(0, 1fr));
  margin-bottom: 3rem;
}
.meta-row { padding: 1.1rem 1.25rem; border-left: 1px solid var(--border); }
.meta-row:first-child { border-left: 0; padding-left: 0; }
.meta-label {
  font-family: 'Quicksand', sans-serif; font-weight: 600;
  font-size: .72rem; letter-spacing: .14em; text-transform: uppercase;
  color: var(--muted); margin-bottom: .3rem;
}
.meta-value {
  font-family: 'Quicksand', sans-serif; font-weight: 700; font-size: 1rem;
  display: inline-flex; align-items: center; gap: .45rem;
}
.meta-value .dot { width: .5rem; height: .5rem; border-radius: 50%; background: var(--live); box-shadow: 0 0 0 3px var(--live-bg); }
.meta-value.mono, .mono {
  font-family: 'JetBrains Mono', ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: .9rem;
}

/* ---------- Sections ---------- */
.section { padding: 2.5rem 0; scroll-margin-top: 5rem; }
.section-head { max-width: 44rem; margin-bottom: 1.75rem; }
h2 {
  font-family: 'Quicksand', sans-serif; font-weight: 700;
  font-size: clamp(1.6rem, 3vw, 2.1rem);
  line-height: 1.15; letter-spacing: -.02em;
  margin: 0 0 .6rem;
}
.section-head p { margin: 0; color: var(--muted); }

.grid { display: grid; gap: 1rem; }
.grid-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.4rem;
  box-shadow: var(--shadow);
}
.card h3 {
  font-family: 'Quicksand', sans-serif; font-weight: 700;
  font-size: 1.12rem; margin: 0 0 .5rem; letter-spacing: -.01em;
}
.card p { margin: 0; color: var(--muted); font-size: .96rem; }
.card-icon {
  width: 2.1rem; height: 2.1rem; border-radius: .7rem;
  display: inline-flex; align-items: center; justify-content: center;
  background: var(--gold-bg); color: var(--gold-strong);
  font-size: 1.05rem; margin-bottom: .9rem;
}
.card-icon.purple { background: rgba(139,119,201,.14); color: var(--purple); }

/* ---------- Steps ---------- */
.steps { display: grid; gap: .9rem; counter-reset: step; }
.step {
  display: grid; grid-template-columns: 2.6rem minmax(0, 1fr);
  gap: 1rem; align-items: start;
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 1.15rem 1.3rem;
}
.step-num {
  counter-increment: step;
  width: 2.1rem; height: 2.1rem; border-radius: 50%;
  display: inline-flex; align-items: center; justify-content: center;
  font-family: 'Quicksand', sans-serif; font-weight: 700; font-size: .95rem;
  color: #1A0A2E; background: linear-gradient(135deg, var(--gold-strong), #E8CD7A);
}
.step-num::before { content: counter(step); }
.step h3 { font-family: 'Quicksand', sans-serif; font-weight: 700; font-size: 1.05rem; margin: .15rem 0 .3rem; }
.step p { margin: 0; color: var(--muted); font-size: .95rem; }

/* ---------- People ---------- */
.person { display: flex; gap: 1rem; align-items: flex-start; }
.avatar {
  width: 2.9rem; height: 2.9rem; border-radius: 50%; flex: 0 0 auto;
  display: inline-flex; align-items: center; justify-content: center;
  font-family: 'Quicksand', sans-serif; font-weight: 700; font-size: 1.05rem;
  color: #1A0A2E; background: linear-gradient(135deg, var(--purple-strong), var(--gold-strong));
}
.person h3 { margin: .1rem 0 .25rem; }
.person .role {
  font-family: 'Quicksand', sans-serif; font-weight: 600; font-size: .8rem;
  letter-spacing: .1em; text-transform: uppercase; color: var(--purple);
  display: block; margin-bottom: .35rem;
}
.person p { margin: 0; color: var(--muted); font-size: .95rem; }

.note {
  margin-top: 1rem; padding: .95rem 1.15rem;
  border: 1px solid var(--border); border-radius: var(--radius-sm);
  background: var(--surface-2); color: var(--muted); font-size: .93rem;
}
.note strong { color: var(--text); }

/* ---------- Code block ---------- */
pre {
  margin: 0; padding: 1.2rem 1.35rem;
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius); overflow-x: auto;
  font-family: 'JetBrains Mono', ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: .88rem; line-height: 1.7; color: var(--text);
}
pre .c { color: var(--muted); }
pre .h { color: var(--gold-strong); }

/* ---------- Footer ---------- */
.footer {
  border-top: 1px solid var(--border);
  margin-top: 2.5rem; padding: 2rem 0 3rem;
}
.footer-inner {
  display: flex; flex-wrap: wrap; align-items: center;
  justify-content: space-between; gap: 1rem;
}
.footer-brand {
  font-family: 'Quicksand', sans-serif; font-weight: 700; font-size: 1rem;
  display: inline-flex; align-items: center; gap: .55rem;
}
.footer-meta { color: var(--muted); font-size: .88rem; }
.footer-meta a { color: var(--purple); text-decoration: none; }
.footer-meta a:hover { text-decoration: underline; }

/* ---------- Responsive ---------- */
@media (max-width: 56rem) {
  .grid-3 { grid-template-columns: 1fr; }
  .meta-rows { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .meta-row:nth-child(3) { border-left: 0; padding-left: 0; }
  .meta-row { border-top: 1px solid var(--border); }
  .meta-row:nth-child(-n+2) { border-top: 0; }
}
@media (max-width: 40rem) {
  .topnav { display: none; }
  .grid-2 { grid-template-columns: 1fr; }
  .hero { padding-top: 2.5rem; }
}