:root {
  --brand-navy: #1E3A8A;
  --brand-navy-deep: #172554;
  --brand-magenta: #BE185D;
  --brand-magenta-deep: #9D174D;
  --brand-gradient: linear-gradient(135deg, #1E3A8A 0%, #BE185D 100%);
  --ink: #0F172A;
  --ink-soft: #334155;
  --paper: #F8FAFC;
  --grid: #E2E8F0;
}

html { scroll-behavior: smooth; }

body {
  font-family: 'Inter', system-ui, -apple-system, Segoe UI, Roboto, sans-serif;
  color: var(--ink);
  background: var(--paper);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

.font-display {
  font-family: 'Inter', system-ui, sans-serif;
  letter-spacing: -0.02em;
  font-weight: 800;
}

.brand-gradient-text {
  background: var(--brand-gradient);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.brand-gradient-bg { background: var(--brand-gradient); }
.bg-navy { background-color: var(--brand-navy); }
.bg-navy-deep { background-color: var(--brand-navy-deep); }
.bg-magenta { background-color: var(--brand-magenta); }
.text-navy { color: var(--brand-navy); }
.text-magenta { color: var(--brand-magenta); }
.border-navy { border-color: var(--brand-navy); }

.grid-bg {
  background-color: var(--paper);
  background-image:
    linear-gradient(var(--grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid) 1px, transparent 1px);
  background-size: 32px 32px;
  background-position: -1px -1px;
}

.hero-grid {
  position: relative;
  background-color: var(--paper);
}
.hero-grid::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(var(--grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid) 1px, transparent 1px);
  background-size: 32px 32px;
  mask-image: radial-gradient(ellipse at top, black 40%, transparent 75%);
  -webkit-mask-image: radial-gradient(ellipse at top, black 40%, transparent 75%);
  pointer-events: none;
}
.hero-grid > * { position: relative; }

.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem 1.5rem;
  background: var(--brand-gradient);
  color: white;
  font-weight: 600;
  border-radius: 9999px;
  box-shadow: 0 4px 14px rgba(190, 24, 93, 0.25);
  transition: transform 0.15s ease, box-shadow 0.15s ease;
  white-space: nowrap;
}
.btn-primary:hover {
  transform: translateY(-1px);
  box-shadow: 0 8px 20px rgba(190, 24, 93, 0.35);
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem 1.5rem;
  background: white;
  color: var(--brand-navy);
  font-weight: 600;
  border: 2px solid var(--brand-navy);
  border-radius: 9999px;
  transition: background 0.15s ease;
}
.btn-secondary:hover { background: var(--paper); }

.nav-link {
  color: var(--ink-soft);
  font-weight: 500;
  padding: 0.5rem 0.75rem;
  border-radius: 0.5rem;
  transition: color 0.15s ease, background 0.15s ease;
}
.nav-link:hover { color: var(--brand-navy); background: #EEF2FF; }
.nav-link[aria-current="page"] { color: var(--brand-navy); font-weight: 600; }

.screenshot-placeholder {
  background: linear-gradient(135deg, #E2E8F0 0%, #CBD5E1 100%);
  border: 1px dashed #94A3B8;
  border-radius: 0.75rem;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #64748B;
  font-size: 0.875rem;
  font-weight: 500;
  text-align: center;
  padding: 1rem;
  position: relative;
  overflow: hidden;
}
.screenshot-placeholder::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,0.4) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.4) 1px, transparent 1px);
  background-size: 20px 20px;
  pointer-events: none;
}
.screenshot-placeholder > * { position: relative; z-index: 1; }

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  background: var(--brand-navy);
  color: white;
  padding: 0.5rem 1rem;
  z-index: 100;
}
.skip-link:focus { left: 1rem; top: 1rem; }

details.mobile-nav > summary { list-style: none; cursor: pointer; }
details.mobile-nav > summary::-webkit-details-marker { display: none; }
details.mobile-nav[open] .hamburger-icon .line-1 { transform: rotate(45deg) translate(5px, 5px); }
details.mobile-nav[open] .hamburger-icon .line-2 { opacity: 0; }
details.mobile-nav[open] .hamburger-icon .line-3 { transform: rotate(-45deg) translate(6px, -6px); }
.hamburger-icon .line { transition: transform 0.2s ease, opacity 0.2s ease; transform-origin: center; }

article.guide { scroll-margin-top: 6rem; }

.toc-link {
  display: block;
  padding: 0.5rem 0.75rem;
  border-left: 2px solid transparent;
  color: var(--ink-soft);
  font-size: 0.9rem;
  transition: all 0.15s ease;
}
.toc-link:hover { color: var(--brand-navy); border-left-color: var(--brand-magenta); }

.feature-card {
  background: white;
  border: 1px solid #E2E8F0;
  border-radius: 1rem;
  padding: 1.5rem;
  transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
}
.feature-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 24px rgba(15, 23, 42, 0.08);
  border-color: #CBD5E1;
}
.feature-icon {
  width: 2.75rem;
  height: 2.75rem;
  border-radius: 0.75rem;
  background: var(--brand-gradient);
  color: white;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1rem;
}

.prose-guide h3 { font-weight: 700; color: var(--ink); margin-top: 1.25rem; }
.prose-guide p  { color: var(--ink-soft); line-height: 1.65; margin-top: 0.75rem; }
.prose-guide ul { margin-top: 0.75rem; padding-left: 1.25rem; list-style: disc; color: var(--ink-soft); }
.prose-guide li { margin-top: 0.375rem; line-height: 1.6; }
.prose-guide strong { color: var(--ink); }