/* ===== CSS Custom Properties ===== */
:root {
  --brand-purple: #7C3AED;
  --brand-purple-dark: #6D28D9;
  --brand-purple-light: #8B5CF6;
  --brand-cyan: #06B6D4;
  --brand-cyan-dark: #0891B2;
  --brand-gradient: linear-gradient(135deg, #7C3AED, #06B6D4);

  /* Light mode (default) */
  --bg-primary: #FFFFFF;
  --bg-secondary: #F8F7FC;
  --bg-card: #FFFFFF;
  --bg-code: #1E1B2E;
  --text-primary: #1A1A2E;
  --text-secondary: #4A4A6A;
  --text-muted: #7A7A9A;
  --text-code: #E2E0F0;
  --border-color: #E8E5F0;
  --card-shadow: 0 1px 3px rgba(0,0,0,0.08), 0 4px 12px rgba(0,0,0,0.04);
  --card-shadow-hover: 0 4px 12px rgba(124,58,237,0.12), 0 8px 24px rgba(0,0,0,0.06);
  --code-copy-bg: rgba(255,255,255,0.1);
  --before-bg: #FEF2F2;
  --before-border: #EF4444;
  --before-text: #991B1B;
  --after-bg: #F0FDF4;
  --after-border: #22C55E;
  --after-text: #166534;
}

[data-theme="dark"] {
  --bg-primary: #0F0E1A;
  --bg-secondary: #1A1830;
  --bg-card: #1E1B2E;
  --bg-code: #12101F;
  --text-primary: #E8E5F0;
  --text-secondary: #B0ADC0;
  --text-muted: #7A7890;
  --text-code: #E2E0F0;
  --border-color: #2A2840;
  --card-shadow: 0 1px 3px rgba(0,0,0,0.3), 0 4px 12px rgba(0,0,0,0.2);
  --card-shadow-hover: 0 4px 12px rgba(124,58,237,0.25), 0 8px 24px rgba(0,0,0,0.3);
  --code-copy-bg: rgba(255,255,255,0.08);
  --before-bg: #2A1215;
  --before-border: #DC2626;
  --before-text: #FCA5A5;
  --after-bg: #122015;
  --after-border: #16A34A;
  --after-text: #86EFAC;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg-primary: #0F0E1A;
    --bg-secondary: #1A1830;
    --bg-card: #1E1B2E;
    --bg-code: #12101F;
    --text-primary: #E8E5F0;
    --text-secondary: #B0ADC0;
    --text-muted: #7A7890;
    --text-code: #E2E0F0;
    --border-color: #2A2840;
    --card-shadow: 0 1px 3px rgba(0,0,0,0.3), 0 4px 12px rgba(0,0,0,0.2);
    --card-shadow-hover: 0 4px 12px rgba(124,58,237,0.25), 0 8px 24px rgba(0,0,0,0.3);
    --code-copy-bg: rgba(255,255,255,0.08);
    --before-bg: #2A1215;
    --before-border: #DC2626;
    --before-text: #FCA5A5;
    --after-bg: #122015;
    --after-border: #16A34A;
    --after-text: #86EFAC;
  }
}

/* ===== Reset & Base ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: 0.01ms !important; transition-duration: 0.01ms !important; }
}

body {
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  transition: background 0.3s ease, color 0.3s ease;
}

img { max-width: 100%; height: auto; display: block; }
a { color: var(--brand-purple-light); text-decoration: none; }
a:hover { text-decoration: underline; }
a:focus-visible { outline: 2px solid var(--brand-purple); outline-offset: 2px; border-radius: 2px; }

/* ===== Layout ===== */
.container {
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 1.25rem;
}

section {
  padding: 4rem 0;
  position: relative;
}

/* #48 — Increased section spacing on desktop */
@media (min-width: 768px) {
  section {
    padding: 6rem 0;
  }
}

/* ===== Header ===== */
/* #45 — Frosted-glass sticky header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: color-mix(in srgb, var(--bg-primary) 80%, transparent);
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.06), 0 1px 0 rgba(0, 0, 0, 0.03);
  padding: 0.75rem 0;
  transition: background 0.3s ease, box-shadow 0.3s ease;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.header-logo {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-weight: 700;
  font-size: 1.125rem;
  color: var(--text-primary);
  text-decoration: none;
}

.header-logo:hover { text-decoration: none; }

.header-logo img {
  width: 28px;
  height: 28px;
}

.header-nav {
  display: flex;
  align-items: center;
  gap: 1.5rem;
}

.header-nav a {
  color: var(--text-secondary);
  font-size: 0.9rem;
  font-weight: 500;
}

.header-nav a:hover { color: var(--brand-purple-light); text-decoration: none; }
.header-nav a.nav-active { color: var(--brand-purple); font-weight: 600; }

/* ===== Theme Toggle ===== */
.theme-toggle {
  background: none;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 0.4rem;
  cursor: pointer;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: border-color 0.2s, color 0.2s;
  width: 36px;
  height: 36px;
}

.theme-toggle:hover { border-color: var(--brand-purple); color: var(--brand-purple); }
.theme-toggle:focus-visible { outline: 2px solid var(--brand-purple); outline-offset: 2px; }

.theme-toggle svg { width: 18px; height: 18px; }

.theme-toggle .icon-moon { display: none; }

[data-theme="dark"] .theme-toggle .icon-sun { display: none; }
[data-theme="dark"] .theme-toggle .icon-moon { display: block; }

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .theme-toggle .icon-sun { display: none; }
  :root:not([data-theme="light"]) .theme-toggle .icon-moon { display: block; }
}

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem 1.5rem;
  border-radius: 8px;
  font-weight: 600;
  font-size: 0.95rem;
  text-decoration: none;
  transition: transform 0.2s cubic-bezier(0.34, 1.56, 0.64, 1), box-shadow 0.2s ease;
  border: none;
  cursor: pointer;
}

.btn:hover { text-decoration: none; transform: translateY(-2px); }
.btn:focus-visible { outline: 2px solid var(--brand-purple); outline-offset: 2px; }

.btn-primary {
  background: var(--brand-gradient);
  color: #FFFFFF;
  box-shadow: 0 2px 8px rgba(124,58,237,0.3);
}

.btn-primary:hover { box-shadow: 0 4px 20px rgba(124,58,237,0.5), 0 0 40px rgba(124,58,237,0.2); }

.btn-secondary {
  background: var(--bg-card);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
  box-shadow: var(--card-shadow);
}

.btn-secondary:hover { border-color: var(--brand-purple); }

.btn svg { width: 18px; height: 18px; }

/* ===== Footer ===== */
.site-footer {
  border-top: 1px solid var(--border-color);
  padding: 2rem 0;
  text-align: center;
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1.5rem;
  flex-wrap: wrap;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.footer-inner a {
  color: var(--text-secondary);
}

.footer-inner a:hover { color: var(--brand-purple-light); }

.footer-sep { color: var(--border-color); }

/* ===== Skip Link ===== */
.skip-link {
  position: absolute;
  top: -100%;
  left: 1rem;
  background: var(--brand-purple);
  color: #FFFFFF;
  padding: 0.5rem 1rem;
  border-radius: 4px;
  z-index: 200;
  font-weight: 600;
}

.skip-link:focus {
  top: 0.5rem;
}

/* ===== Scroll entrance animations ===== */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.reveal.revealed {
  opacity: 1;
  transform: translateY(0);
}

.reveal[style*="--delay"] {
  transition-delay: var(--delay);
}

@media (prefers-reduced-motion: reduce) {
  .reveal {
    opacity: 1;
    transform: none;
    transition: none;
  }
}

/* ===== Soft section dividers ===== */
.section-divider {
  position: relative;
}

.section-divider::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 80px;
  background: linear-gradient(to bottom, var(--bg-primary), transparent);
  pointer-events: none;
  z-index: 1;
}

.section-divider-reverse::before {
  background: linear-gradient(to bottom, var(--bg-secondary), transparent);
}

.section-divider-bottom::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 80px;
  background: linear-gradient(to top, var(--bg-primary), transparent);
  pointer-events: none;
  z-index: 1;
}

.section-divider-bottom-alt::after {
  background: linear-gradient(to top, var(--bg-secondary), transparent);
}

/* ===== Dot-grid texture on secondary sections ===== */
section.features,
section.comparison {
  position: relative;
}
section.features::before,
section.comparison::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: radial-gradient(circle, var(--text-muted) 1px, transparent 1px);
  background-size: 24px 24px;
  opacity: 0.12;
  pointer-events: none;
  z-index: 0;
}
section.features > *,
section.comparison > * {
  position: relative;
  z-index: 1;
}

/* ===== Hamburger Menu ===== */
.hamburger-btn {
  display: none;
  background: none;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 0.4rem;
  cursor: pointer;
  color: var(--text-secondary);
  width: 36px;
  height: 36px;
  align-items: center;
  justify-content: center;
  transition: border-color 0.2s, color 0.2s;
}

.hamburger-btn:hover { border-color: var(--brand-purple); color: var(--brand-purple); }
.hamburger-btn:focus-visible { outline: 2px solid var(--brand-purple); outline-offset: 2px; }

.hamburger-btn svg { width: 20px; height: 20px; }
.hamburger-btn .icon-close { display: none; }

.mobile-nav {
  display: none;
  position: absolute;
  top: 100%;
  left: 0;
  right: 0;
  background: var(--bg-primary);
  border-bottom: 1px solid var(--border-color);
  padding: 0.75rem 1.25rem 1rem;
  z-index: 99;
  flex-direction: column;
  gap: 0.25rem;
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

.mobile-nav a {
  display: block;
  padding: 0.6rem 0.5rem;
  color: var(--text-secondary);
  font-size: 0.95rem;
  font-weight: 500;
  border-radius: 6px;
  transition: background 0.15s, color 0.15s;
}

.mobile-nav a:hover { background: var(--bg-secondary); color: var(--brand-purple-light); text-decoration: none; }
.mobile-nav a.nav-active { color: var(--brand-purple); font-weight: 600; }

.mobile-nav-open .mobile-nav { display: flex; }
.mobile-nav-open .hamburger-btn .icon-menu { display: none; }
.mobile-nav-open .hamburger-btn .icon-close { display: block; }
/* ===== Responsive (shared) ===== */
@media (max-width: 480px) {
  .header-nav .nav-link { display: none; }
  .hamburger-btn { display: flex; }
  .site-header { position: relative; }
}