:root {
  /* Color palette */
  --amber: #d97706;
  --amber-bg: #fffbeb;
  --amber-border: #fde68a;
  --indigo: #4c6ef5;
  --indigo-bg: #eef2ff;
  --indigo-border: #c7d2fe;
  --teal: #0d9488;
  --teal-bg: #f0fdfa;
  --teal-border: #99f6e4;
  --red: #ef4444;
  --red-bg: #fef2f2;
  --red-border: #fecaca;
  --green: #16a34a;
  --green-bg: #f0fdf4;
  --green-border: #86efac;

  /* Surfaces */
  --bg: #f6f8fa;
  --surface: #ffffff;
  --surface-2: #f8fafc;
  --border: #e2e8f0;
  --text: #1e293b;
  --text-2: #475569;
  --text-3: #94a3b8;
  --code-bg: #0f172a;
  --code-text: #e2e8f0;

  /* Typography */
  --font-display: 'Outfit', 'Inter', sans-serif;
  --font-body: 'Inter', system-ui, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', 'Courier New', monospace;

  /* Shape */
  --radius: 0.5rem;
  --radius-lg: 0.875rem;
  --nav-h: 64px;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body { background: var(--bg); color: var(--text); font-family: var(--font-body); font-size: 0.9375rem; line-height: 1.6; }

@import url('https://fonts.googleapis.com/css2?family=Outfit:wght@400;600;700;800&family=Inter:wght@400;500;600&family=JetBrains+Mono:wght@400;500&display=swap');

/* ---- NAV ---- */
.nav {
  position: sticky; top: 0; z-index: 100;
  height: var(--nav-h);
  background: rgba(255,255,255,0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}
.nav-inner { max-width: 900px; margin: 0 auto; padding: 0 1.5rem; height: 100%; display: flex; align-items: center; justify-content: space-between; }
.nav-brand { font-family: var(--font-display); font-weight: 800; font-size: 1.05rem; color: var(--text); text-decoration: none; }
.nav-brand span { color: var(--amber); }
.nav-links { display: flex; gap: 0.25rem; align-items: center; }
.nav-link { color: var(--text-2); text-decoration: none; font-weight: 500; font-size: 0.875rem; padding: 0.35rem 0.75rem; border-radius: var(--radius); transition: background 0.15s, color 0.15s; }
.nav-link:hover, .nav-link.active { background: var(--amber-bg); color: var(--amber); }

/* ---- HERO ---- */
.hero {
  background: linear-gradient(135deg, #0f172a 0%, #1e1b4b 100%);
  padding: 5rem 1.5rem 4rem;
  text-align: center;
}
.hero-eyebrow {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 500;
  color: var(--amber);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  margin-bottom: 1rem;
}
.hero h1 {
  font-family: var(--font-display);
  font-size: 2.75rem;
  font-weight: 800;
  color: #f8fafc;
  letter-spacing: -0.03em;
  line-height: 1.1;
  margin-bottom: 1rem;
  max-width: 640px;
  margin-left: auto;
  margin-right: auto;
}
.hero-sub {
  font-size: 1rem;
  color: #94a3b8;
  max-width: 540px;
  margin: 0 auto 2.5rem;
  line-height: 1.7;
}
.hero-cta { display: inline-flex; gap: 1rem; flex-wrap: wrap; justify-content: center; }

/* ---- PROGRESS TRACK ---- */
.progress-track {
  max-width: 700px;
  margin: 3rem auto;
  padding: 0 1.5rem;
}
.progress-steps {
  display: flex;
  align-items: center;
  justify-content: space-between;
  position: relative;
}
.progress-line {
  position: absolute;
  top: 50%;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--border);
  z-index: 0;
  transform: translateY(-50%);
}
.progress-line-fill {
  height: 100%;
  background: var(--amber);
  transition: width 0.4s;
}
.step-dot {
  width: 2.25rem;
  height: 2.25rem;
  border-radius: 50%;
  background: var(--surface);
  border: 2px solid var(--border);
  color: var(--text-3);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 600;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  z-index: 1;
  text-decoration: none;
  transition: background 0.2s, border-color 0.2s, color 0.2s;
}
.step-dot.active {
  background: var(--amber);
  border-color: var(--amber);
  color: white;
}
.step-dot.done {
  background: var(--green-bg);
  border-color: var(--green);
  color: var(--green);
}
.step-dot.done::after { content: "✓"; }
.progress-labels {
  display: flex;
  justify-content: space-between;
  margin-top: 0.5rem;
}
.step-label {
  font-size: 0.68rem;
  color: var(--text-3);
  text-align: center;
  width: 2.25rem;
  font-family: var(--font-mono);
}
.step-label.active { color: var(--amber); font-weight: 600; }
.step-label.done { color: var(--green); }

/* ---- STEP LAYOUT ---- */
.step-layout {
  max-width: 760px;
  margin: 0 auto;
  padding: 2rem 1.5rem 4rem;
}
.step-header-section {
  margin-bottom: 2rem;
}
.step-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  background: var(--amber-bg);
  border: 1px solid var(--amber-border);
  border-radius: 99px;
  padding: 0.25rem 0.75rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--amber);
  margin-bottom: 0.75rem;
}
.step-title {
  font-family: var(--font-display);
  font-size: 1.75rem;
  font-weight: 800;
  color: var(--text);
  letter-spacing: -0.025em;
  margin-bottom: 0.5rem;
}
.step-sub { color: var(--text-3); font-size: 0.9375rem; }

/* ---- TASK CARD ---- */
.task-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  margin-bottom: 1.25rem;
}
.task-card-header {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 1rem;
}
.task-num {
  width: 1.75rem;
  height: 1.75rem;
  border-radius: 50%;
  background: var(--amber);
  color: white;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}
.task-title { font-weight: 700; font-size: 0.9375rem; }

/* ---- CHECKLIST ---- */
.checklist { list-style: none; padding: 0; }
.checklist li {
  display: flex;
  align-items: flex-start;
  gap: 0.6rem;
  font-size: 0.875rem;
  color: var(--text-2);
  padding: 0.4rem 0;
  border-bottom: 1px solid var(--border);
  cursor: pointer;
  transition: background 0.1s;
  border-radius: 0.25rem;
}
.checklist li:last-child { border-bottom: none; }
.checklist li.checked { color: var(--text-3); text-decoration: line-through; }
.check-box {
  width: 1.1rem;
  height: 1.1rem;
  border: 2px solid var(--border);
  border-radius: 0.25rem;
  flex-shrink: 0;
  margin-top: 0.1rem;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.65rem;
  color: white;
  background: transparent;
  transition: all 0.15s;
}
.checklist li.checked .check-box { background: var(--green); border-color: var(--green); }
.checklist li.checked .check-box::after { content: "✓"; }

/* ---- CODE BLOCK ---- */
.code-block {
  background: var(--code-bg);
  color: var(--code-text);
  padding: 1.25rem 1.5rem;
  border-radius: var(--radius);
  font-family: var(--font-mono);
  font-size: 0.78rem;
  line-height: 1.9;
  overflow-x: auto;
  margin: 1rem 0;
}
.code-block .cmt { color: #64748b; }
.code-block .kw { color: #93c5fd; }
.code-block .str { color: #86efac; }
.code-block .fn { color: #fde68a; }
.code-block .var { color: #f0abfc; }
.code-block .num { color: #fb923c; }

/* ---- CALLOUT ---- */
.callout {
  border-radius: var(--radius);
  padding: 1rem 1.25rem;
  margin: 1.25rem 0;
  font-size: 0.875rem;
  line-height: 1.6;
}
.callout-title { font-weight: 700; margin-bottom: 0.25rem; }
.callout-tip { background: var(--teal-bg); border: 1px solid var(--teal-border); }
.callout-tip .callout-title { color: var(--teal); }
.callout-warning { background: var(--amber-bg); border: 1px solid var(--amber-border); }
.callout-warning .callout-title { color: var(--amber); }
.callout-success { background: var(--green-bg); border: 1px solid var(--green-border); }
.callout-success .callout-title { color: var(--green); }

/* ---- STEP NAV ---- */
.step-nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 2.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border);
  gap: 1rem;
  flex-wrap: wrap;
}

/* ---- BUTTONS ---- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.6rem 1.25rem;
  border-radius: var(--radius);
  font-weight: 600;
  font-size: 0.875rem;
  text-decoration: none;
  border: none;
  cursor: pointer;
  transition: opacity 0.15s, transform 0.1s;
}
.btn:hover { opacity: 0.88; transform: translateY(-1px); }
.btn-amber { background: var(--amber); color: white; }
.btn-outline { background: transparent; border: 1px solid var(--border); color: var(--text-2); }
.btn-green { background: var(--green); color: white; }

/* ---- BADGE ---- */
.badge {
  display: inline-block;
  padding: 0.2rem 0.6rem;
  border-radius: 99px;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}
.badge-amber { background: var(--amber-bg); border: 1px solid var(--amber-border); color: var(--amber); }
.badge-green { background: var(--green-bg); border: 1px solid var(--green-border); color: var(--green); }
.badge-gray { background: var(--surface-2); border: 1px solid var(--border); color: var(--text-3); }
.badge-teal { background: var(--teal-bg); border: 1px solid var(--teal-border); color: var(--teal); }

/* ---- CODE TABS ---- */
.code-tabs-wrap { border: 1px solid var(--border); border-radius: var(--radius-lg); overflow: hidden; margin: 1rem 0; }
.code-tabs-header { display: flex; background: var(--surface-2); border-bottom: 1px solid var(--border); }
.code-tab { background: none; border: none; padding: 0.6rem 1rem; font-family: var(--font-mono); font-size: 0.75rem; font-weight: 600; color: var(--text-3); cursor: pointer; transition: background 0.15s, color 0.15s; }
.code-tab.active { background: var(--code-bg); color: var(--amber); }
.code-tab-content { display: none; }
.code-tab-content.active { display: block; }
.code-tab-content .code-block { border-radius: 0; margin: 0; border: none; }

/* ---- HOME PAGE ---- */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1rem;
  max-width: 900px;
  margin: 0 auto 4rem;
  padding: 0 1.5rem;
}
.feature-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
}
.feature-icon { font-size: 1.5rem; margin-bottom: 0.75rem; }
.feature-title { font-weight: 700; margin-bottom: 0.35rem; font-size: 0.9375rem; }
.feature-desc { font-size: 0.8rem; color: var(--text-3); line-height: 1.6; }

.steps-overview {
  max-width: 700px;
  margin: 0 auto 4rem;
  padding: 0 1.5rem;
}
.overview-step {
  display: flex;
  gap: 1.25rem;
  align-items: flex-start;
  padding: 1.25rem 0;
  border-bottom: 1px solid var(--border);
}
.overview-step:last-child { border-bottom: none; }
.overview-num {
  width: 2.5rem;
  height: 2.5rem;
  background: var(--amber);
  color: white;
  border-radius: 50%;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 0.875rem;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}
.overview-title { font-weight: 700; margin-bottom: 0.25rem; }
.overview-sub { font-size: 0.825rem; color: var(--text-3); }
.overview-time { font-family: var(--font-mono); font-size: 0.68rem; color: var(--amber); background: var(--amber-bg); border: 1px solid var(--amber-border); border-radius: 99px; padding: 0.1rem 0.5rem; margin-left: auto; flex-shrink: 0; align-self: flex-start; margin-top: 0.25rem; }

/* ---- SUCCESS ---- */
.success-layout {
  max-width: 620px;
  margin: 0 auto;
  padding: 4rem 1.5rem;
  text-align: center;
}

/* ---- FOOTER ---- */
.footer {
  background: #0f172a;
  color: #94a3b8;
  padding: 3rem 1.5rem 1.5rem;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr;
  gap: 2rem;
  max-width: 900px;
  margin: 0 auto 2rem;
}
.footer-brand { font-family: var(--font-display); font-weight: 800; font-size: 1rem; color: #f8fafc; margin-bottom: 0.5rem; }
.footer-brand span { color: var(--amber); }
.footer-desc { font-size: 0.8rem; color: #64748b; line-height: 1.6; }
.footer-col-title { font-family: var(--font-mono); font-size: 0.68rem; font-weight: 600; letter-spacing: 0.08em; text-transform: uppercase; color: #f8fafc; margin-bottom: 0.75rem; }
.footer-links { list-style: none; }
.footer-links li { margin-bottom: 0.4rem; }
.footer-links a { color: #94a3b8; text-decoration: none; font-size: 0.8rem; transition: color 0.15s; }
.footer-links a:hover { color: var(--amber); }
.footer-bottom { text-align: center; padding-top: 1.5rem; border-top: 1px solid #1e293b; font-size: 0.75rem; color: #475569; max-width: 900px; margin: 0 auto; }

/* ---- RESPONSIVE ---- */
@media (max-width: 768px) {
  .feature-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .hero h1 { font-size: 2rem; }
  .step-title { font-size: 1.4rem; }
}

/* ═══════════════════════════════════════════════
   DARK THEME
   ═══════════════════════════════════════════════ */
[data-theme="dark"] {
  --bg:          #0f172a;
  --bg-card:     #1e293b;
  --bg-hover:    #334155;
  --bg-tag:      #1e293b;
  --border:      #334155;
  --border-dark: #475569;
  --text:        #f1f5f9;
  --text-2:      #cbd5e1;
  --text-3:      #94a3b8;
  --text-4:      #64748b;
  --code-bg:     #0f172a;
  --code-text:   #e2e8f0;
}
[data-theme="dark"] .nav { background: rgba(15,23,42,0.95); border-bottom-color: var(--border); }
[data-theme="dark"] body { background: var(--bg); color: var(--text); }

/* Theme toggle */
.theme-toggle {
  background: none;
  border: 1px solid var(--border);
  color: var(--text-3);
  cursor: pointer;
  border-radius: 6px;
  padding: 0.3rem 0.65rem;
  font-size: 0.85rem;
  line-height: 1;
  margin-left: 0.5rem;
  transition: background 0.15s, color 0.15s;
}
.theme-toggle:hover { background: var(--bg-hover); color: var(--text); }