/* ============================================================================
   DuDuClaw — Landing page
   Calm Glass design system, matched to the in-app dashboard (web/src/index.css):
   cool graphite neutrals + a single amber accent, flat hairline panels for
   content, glass for chrome, an ambient graphite/amber/grid stage, system-ui
   type, 0.75rem radii, restrained motion. Light + dark via prefers-color-scheme.
   ========================================================================== */

/* ───────────────────────── Tokens ───────────────────────── */
:root {
  /* Graphite-titanium neutral ramp (cool, low-chroma OKLCH) — same as dashboard */
  --stone-50:  oklch(97.8% 0.003 250);
  --stone-100: oklch(94.6% 0.004 250);
  --stone-200: oklch(88.6% 0.006 251);
  --stone-300: oklch(78.2% 0.008 252);
  --stone-400: oklch(64.4% 0.011 253);
  --stone-500: oklch(52.5% 0.013 255);
  --stone-600: oklch(42.4% 0.015 257);
  --stone-700: oklch(33.2% 0.016 259);
  --stone-800: oklch(25.2% 0.017 261);
  --stone-900: oklch(19.4% 0.017 263);
  --stone-950: oklch(14.5% 0.016 265);

  /* Brand amber — the single signature accent */
  --amber-100: #fef3c7;
  --amber-300: #fcd34d;
  --amber-400: #fbbf24;
  --amber-500: #f59e0b;
  --amber-600: #d97706;
  --amber-700: #b45309;
  --accent-400: #fb923c;

  --radius: 0.75rem;
  --radius-lg: 1rem;
  --radius-sm: 0.5rem;

  --font-sans: ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont,
    "Segoe UI", "Noto Sans TC", "Helvetica Neue", Arial, sans-serif;
  --font-mono: ui-monospace, "SF Mono", SFMono-Regular, Menlo, Consolas,
    "Noto Sans Mono CJK TC", monospace;

  /* Semantic surfaces (light) */
  --app-bg: oklch(95.5% 0.006 250);
  --fg: var(--stone-800);
  --fg-muted: var(--stone-500);
  --fg-faint: var(--stone-400);

  --panel-fill: oklch(99.4% 0.001 250 / 0.86);
  --panel-fill-hover: oklch(100% 0 0 / 0.96);
  --panel-border: oklch(82% 0.006 255 / 0.7);
  --panel-border-strong: oklch(74% 0.008 255 / 0.85);
  --panel-shadow-hover: 0 10px 30px -16px oklch(30% 0.02 260 / 0.22);

  --glass-fill: linear-gradient(165deg, oklch(100% 0 0 / 0.72), oklch(98% 0.004 250 / 0.5));
  --glass-border: oklch(100% 0 0 / 0.65);
  --glass-edge: inset 0 1px 0 0 oklch(100% 0 0 / 0.9);

  --grid-line: oklch(40% 0.02 255 / 0.04);
  --hairline: oklch(82% 0.006 255 / 0.7);
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

@media (prefers-color-scheme: dark) {
  :root {
    --app-bg: oklch(15% 0.014 263);
    --fg: var(--stone-100);
    --fg-muted: var(--stone-400);
    --fg-faint: var(--stone-500);

    --panel-fill: oklch(23% 0.014 262 / 0.66);
    --panel-fill-hover: oklch(26% 0.015 261 / 0.82);
    --panel-border: oklch(100% 0 0 / 0.08);
    --panel-border-strong: oklch(100% 0 0 / 0.14);
    --panel-shadow-hover: 0 14px 36px -18px oklch(0% 0 0 / 0.6);

    --glass-fill: linear-gradient(165deg, oklch(26% 0.015 260 / 0.62), oklch(20% 0.015 262 / 0.5));
    --glass-border: oklch(100% 0 0 / 0.1);
    --glass-edge: inset 0 1px 0 0 oklch(100% 0 0 / 0.13);

    --grid-line: oklch(85% 0.02 255 / 0.03);
    --hairline: oklch(100% 0 0 / 0.08);
  }
}

/* ───────────────────────── Reset & base ───────────────────────── */
*, *::before, *::after { box-sizing: border-box; }
* { margin: 0; }

html { scroll-behavior: smooth; scroll-padding-top: 5rem; -webkit-text-size-adjust: 100%; }

body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.65;
  color: var(--fg);
  background: var(--app-bg);
  font-feature-settings: "tnum" 1;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1, h2, h3 { letter-spacing: -0.02em; line-height: 1.15; color: var(--fg); font-weight: 650; }
a { color: inherit; }
strong { font-weight: 650; color: var(--fg); }
code {
  font-family: var(--font-mono);
  font-size: 0.875em;
  padding: 0.15em 0.45em;
  border-radius: var(--radius-sm);
  background: oklch(60% 0.015 255 / 0.12);
  border: 1px solid var(--hairline);
}
::selection { background: oklch(82% 0.14 80 / 0.4); }
::-webkit-scrollbar { width: 8px; height: 8px; }
::-webkit-scrollbar-thumb { background: oklch(60% 0.015 255 / 0.45); border-radius: 4px; }

/* ───────────────────────── Ambient stage (fixed, refracted by glass) ───────── */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -10;
  pointer-events: none;
  background:
    radial-gradient(60rem 40rem at 8% -16%, oklch(82% 0.13 75 / 0.10), transparent 60%),
    radial-gradient(52rem 36rem at 104% 6%, oklch(70% 0.09 255 / 0.05), transparent 58%),
    var(--app-bg);
}
@media (prefers-color-scheme: dark) {
  body::before {
    background:
      radial-gradient(60rem 40rem at 8% -16%, oklch(60% 0.13 70 / 0.13), transparent 60%),
      radial-gradient(52rem 36rem at 104% 6%, oklch(50% 0.08 260 / 0.10), transparent 58%),
      var(--app-bg);
  }
}
/* fine engineering grid, fading from the top */
body::after {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -9;
  pointer-events: none;
  background-image:
    linear-gradient(var(--grid-line) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-line) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(90rem 64rem at 35% 0%, black 25%, transparent 72%);
  -webkit-mask-image: radial-gradient(90rem 64rem at 35% 0%, black 25%, transparent 72%);
}

/* ───────────────────────── Layout ───────────────────────── */
.container { width: 100%; max-width: 72rem; margin-inline: auto; padding-inline: 1.5rem; }

section.container { padding-block: clamp(3.5rem, 8vw, 6rem); }
section.container > h2 {
  font-size: clamp(1.75rem, 3.5vw, 2.4rem);
  text-align: center;
}
section.container > .lede { text-align: center; }

/* shared section lede */
.lede {
  max-width: 44rem;
  margin-inline: auto;
  margin-top: 1rem;
  font-size: clamp(1rem, 1.6vw, 1.15rem);
  color: var(--fg-muted);
}
.quiet { color: var(--fg-faint); font-size: 0.875rem; }

/* ───────────────────────── Header (sticky glass chrome) ───────────────────── */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: var(--glass-fill);
  border-bottom: 1px solid var(--glass-border);
  box-shadow: var(--glass-edge);
  -webkit-backdrop-filter: blur(24px) saturate(170%);
  backdrop-filter: blur(24px) saturate(170%);
}
.site-header .header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  height: 4rem;
}
.brand { display: inline-flex; align-items: center; gap: 0.6rem; font-weight: 650; font-size: 1.05rem; letter-spacing: -0.01em; }
.brand .paw {
  display: grid; place-items: center;
  width: 2rem; height: 2rem; border-radius: 0.625rem;
  font-size: 1.05rem;
  background: linear-gradient(180deg, var(--amber-400), var(--amber-500));
  box-shadow: 0 4px 16px -4px oklch(70% 0.15 75 / 0.6);
}
.site-header nav { display: flex; align-items: center; gap: 0.35rem; flex-wrap: wrap; }
.site-header nav a {
  text-decoration: none;
  color: var(--fg-muted);
  font-size: 0.9rem;
  font-weight: 500;
  padding: 0.4rem 0.7rem;
  border-radius: var(--radius-sm);
  transition: color 150ms ease, background-color 150ms ease;
}
.site-header nav a:hover { color: var(--fg); background: oklch(60% 0.015 255 / 0.1); }
.site-header nav a.nav-cta {
  color: var(--amber-700);
  background: oklch(82% 0.14 80 / 0.14);
  border: 1px solid oklch(80% 0.13 80 / 0.3);
}
@media (prefers-color-scheme: dark) { .site-header nav a.nav-cta { color: var(--amber-300); } }

/* ───────────────────────── Hero ───────────────────────── */
.hero { text-align: center; padding-block: clamp(4rem, 11vw, 8rem) clamp(3rem, 7vw, 5rem); }
.eyebrow {
  display: inline-flex; align-items: center; gap: 0.5rem;
  font-size: 0.8rem; font-weight: 550; letter-spacing: 0.01em;
  color: var(--amber-700);
  padding: 0.35rem 0.8rem;
  border-radius: 999px;
  background: oklch(82% 0.14 80 / 0.12);
  border: 1px solid oklch(80% 0.13 80 / 0.28);
  margin-bottom: 1.5rem;
}
@media (prefers-color-scheme: dark) { .eyebrow { color: var(--amber-300); } }
.eyebrow .dot { width: 0.45rem; height: 0.45rem; border-radius: 50%; background: var(--amber-500); box-shadow: 0 0 0 3px oklch(80% 0.13 80 / 0.25); }

.hero h1 {
  font-size: clamp(2.25rem, 6vw, 4rem);
  font-weight: 680;
  line-height: 1.08;
}
.hero .accent {
  background: linear-gradient(120deg, var(--amber-500), var(--accent-400));
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent; color: transparent;
}
.hero .lede { margin-top: 1.5rem; font-size: clamp(1.05rem, 2vw, 1.25rem); line-height: 1.7; }

.cta-row { margin-top: 2.25rem; display: flex; gap: 0.85rem; justify-content: center; flex-wrap: wrap; }
.hero .quiet { margin-top: 1.5rem; }

/* ───────────────────────── Buttons ───────────────────────── */
.cta {
  --cta-pad-y: 0.7rem; --cta-pad-x: 1.3rem;
  display: inline-flex; align-items: center; justify-content: center; gap: 0.4rem;
  font-family: inherit; font-size: 0.95rem; font-weight: 600;
  padding: var(--cta-pad-y) var(--cta-pad-x);
  border-radius: var(--radius);
  border: 1px solid transparent;
  text-decoration: none;
  cursor: pointer;
  transition: transform 160ms var(--ease), box-shadow 200ms var(--ease),
    background-color 160ms ease, border-color 160ms ease, color 160ms ease;
}
.cta:active { transform: translateY(0.5px) scale(0.99); }
.cta-primary {
  color: #2a1a02;
  background: linear-gradient(180deg, var(--amber-400), var(--amber-500));
  box-shadow: 0 8px 22px -10px oklch(70% 0.15 75 / 0.7), var(--glass-edge);
}
.cta-primary:hover { transform: translateY(-1px); box-shadow: 0 14px 32px -10px oklch(70% 0.16 75 / 0.8), var(--glass-edge); }
.cta-secondary {
  color: var(--fg);
  background: var(--panel-fill);
  border-color: var(--panel-border-strong);
}
.cta-secondary:hover { transform: translateY(-1px); background: var(--panel-fill-hover); border-color: var(--amber-500); }
.cta:disabled, .cta[disabled] { opacity: 0.55; cursor: not-allowed; transform: none; box-shadow: none; }

/* ───────────────────────── Panels / card grids ───────────────────────── */
.grid-3, .grid-2 { display: grid; gap: 1.25rem; margin-top: 2.5rem; }
.grid-3 { grid-template-columns: repeat(auto-fit, minmax(16rem, 1fr)); }
.grid-2 { grid-template-columns: repeat(auto-fit, minmax(20rem, 1fr)); }

.grid-3 > article, .grid-2 > article {
  background: var(--panel-fill);
  border: 1px solid var(--panel-border);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  transition: border-color 180ms ease, box-shadow 220ms var(--ease), transform 220ms var(--ease);
}
.grid-3 > article:hover, .grid-2 > article:hover {
  transform: translateY(-2px);
  border-color: var(--panel-border-strong);
  box-shadow: var(--panel-shadow-hover);
}
.grid-3 > article h3, .grid-2 > article h3 { font-size: 1.1rem; margin-bottom: 0.55rem; }
.grid-3 > article p, .grid-2 > article p { color: var(--fg-muted); font-size: 0.95rem; }

/* ───────────────────────── Pricing ───────────────────────── */
.grid-pricing {
  display: grid; gap: 1.25rem; margin-top: 2.75rem;
  grid-template-columns: repeat(auto-fit, minmax(15rem, 1fr));
  align-items: stretch;
}
.plan {
  position: relative;
  display: flex; flex-direction: column;
  background: var(--panel-fill);
  border: 1px solid var(--panel-border);
  border-radius: var(--radius-lg);
  padding: 1.75rem 1.5rem;
  transition: border-color 180ms ease, box-shadow 220ms var(--ease), transform 220ms var(--ease);
}
.plan:hover { transform: translateY(-2px); border-color: var(--panel-border-strong); box-shadow: var(--panel-shadow-hover); }
.plan h3 { font-size: 1.15rem; }
.plan .price { margin: 0.85rem 0 0.25rem; font-size: 2rem; font-weight: 680; letter-spacing: -0.03em; }
.plan .price .period { font-size: 0.9rem; font-weight: 500; color: var(--fg-faint); letter-spacing: 0; }
.plan ul { list-style: none; padding: 0; margin: 1.1rem 0 1.5rem; display: grid; gap: 0.55rem; }
.plan ul li {
  position: relative; padding-left: 1.5rem;
  font-size: 0.92rem; color: var(--fg-muted);
}
.plan ul li::before {
  content: ""; position: absolute; left: 0; top: 0.5em;
  width: 0.7rem; height: 0.4rem;
  border-left: 2px solid var(--amber-500); border-bottom: 2px solid var(--amber-500);
  transform: rotate(-45deg) translateY(-2px);
  border-radius: 1px;
}
.plan .cta { margin-top: auto; width: 100%; }

.plan.featured {
  border-color: oklch(80% 0.13 80 / 0.55);
  box-shadow: 0 16px 44px -22px oklch(70% 0.15 75 / 0.5);
  background:
    linear-gradient(180deg, oklch(82% 0.14 80 / 0.06), transparent 40%),
    var(--panel-fill);
}
.plan.featured .badge {
  position: absolute; top: -0.7rem; left: 50%; transform: translateX(-50%);
  font-size: 0.72rem; font-weight: 650; letter-spacing: 0.04em;
  color: #2a1a02;
  padding: 0.28rem 0.75rem; border-radius: 999px;
  background: linear-gradient(180deg, var(--amber-400), var(--amber-500));
  box-shadow: 0 6px 16px -6px oklch(70% 0.15 75 / 0.7);
  white-space: nowrap;
}

/* ───────────────────────── Self-Host block ───────────────────────── */
.self-host {
  margin-top: 2rem;
  background:
    linear-gradient(180deg, oklch(60% 0.02 255 / 0.05), transparent 50%),
    var(--panel-fill);
  border: 1px solid var(--panel-border);
  border-radius: var(--radius-lg);
  padding: 2rem;
}
.self-host h3 { font-size: 1.25rem; }
.self-host > p { color: var(--fg-muted); margin-top: 0.5rem; max-width: 48rem; }
.self-host ul { list-style: none; padding: 0; margin: 1.25rem 0 1.5rem; display: grid; gap: 0.55rem; grid-template-columns: repeat(auto-fit, minmax(18rem, 1fr)); }
.self-host ul li { position: relative; padding-left: 1.5rem; font-size: 0.92rem; color: var(--fg-muted); }
.self-host ul li::before {
  content: ""; position: absolute; left: 0; top: 0.5em;
  width: 0.7rem; height: 0.4rem;
  border-left: 2px solid var(--amber-500); border-bottom: 2px solid var(--amber-500);
  transform: rotate(-45deg) translateY(-2px); border-radius: 1px;
}

/* ───────────────────────── Subscribe notice + form ───────────────────────── */
.subscribe-notice {
  margin-top: 2rem;
  background: var(--panel-fill);
  border: 1px solid var(--panel-border);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
}
.subscribe-notice h3 { font-size: 1.1rem; margin-bottom: 0.85rem; }
.subscribe-notice ul { padding-left: 1.1rem; margin-bottom: 1.5rem; display: grid; gap: 0.65rem; }
.subscribe-notice li { color: var(--fg-muted); font-size: 0.9rem; line-height: 1.6; }
.subscribe-notice a { color: var(--amber-700); text-underline-offset: 2px; }
@media (prefers-color-scheme: dark) { .subscribe-notice a, .founder a, .site-footer a, .consent a { color: var(--amber-400); } }

.checkout-email { display: grid; gap: 0.45rem; margin-bottom: 1.1rem; }
.checkout-email label { font-size: 0.85rem; font-weight: 550; color: var(--fg); }
.checkout-email input {
  font-family: inherit; font-size: 0.95rem;
  padding: 0.7rem 0.9rem;
  color: var(--fg);
  background: var(--app-bg);
  border: 1px solid var(--panel-border-strong);
  border-radius: var(--radius);
  transition: border-color 150ms ease, box-shadow 150ms ease;
}
.checkout-email input:focus {
  outline: none;
  border-color: var(--amber-500);
  box-shadow: 0 0 0 3px oklch(80% 0.13 80 / 0.22);
}
.consent { display: flex; align-items: flex-start; gap: 0.6rem; font-size: 0.875rem; color: var(--fg-muted); cursor: pointer; }
.consent input { margin-top: 0.25rem; width: 1.05rem; height: 1.05rem; accent-color: var(--amber-500); flex-shrink: 0; }
.consent a { color: var(--amber-700); }

/* ───────────────────────── FAQ ───────────────────────── */
#faq { max-width: 52rem; margin-inline: auto; }
#faq details {
  background: var(--panel-fill);
  border: 1px solid var(--panel-border);
  border-radius: var(--radius);
  margin-top: 0.75rem;
  overflow: hidden;
  transition: border-color 160ms ease;
}
#faq details[open] { border-color: var(--panel-border-strong); }
#faq summary {
  cursor: pointer; list-style: none;
  padding: 1.1rem 1.35rem;
  font-weight: 550; font-size: 1rem; color: var(--fg);
  display: flex; align-items: center; justify-content: space-between; gap: 1rem;
}
#faq summary::-webkit-details-marker { display: none; }
#faq summary::after {
  content: "+"; font-size: 1.3rem; font-weight: 400; color: var(--amber-600);
  transition: transform 200ms var(--ease);
  line-height: 1;
}
#faq details[open] summary::after { transform: rotate(45deg); }
#faq details p { padding: 0 1.35rem 1.25rem; color: var(--fg-muted); font-size: 0.95rem; }

/* ───────────────────────── Founder ───────────────────────── */
.founder { max-width: 48rem; }
.founder h2 { text-align: left; font-size: clamp(1.5rem, 3vw, 2rem); }
.founder p { color: var(--fg-muted); margin-top: 1rem; }
.founder a { color: var(--amber-700); font-weight: 550; }

/* ───────────────────────── Footer ───────────────────────── */
.site-footer {
  border-top: 1px solid var(--hairline);
  padding-block: 2.5rem 3rem;
  margin-top: 2rem;
}
.footer-biz p { color: var(--fg-faint); font-size: 0.85rem; line-height: 1.7; }
.footer-biz a { color: var(--fg-muted); }
.footer-links { display: flex; gap: 1.25rem; flex-wrap: wrap; margin: 1.25rem 0; }
.footer-links a { color: var(--fg-muted); font-size: 0.875rem; text-decoration: none; }
.footer-links a:hover { color: var(--amber-600); }
.footer-copy { color: var(--fg-faint); font-size: 0.8rem; }

/* ───────────────────────── Checkout overlay ───────────────────────── */
#checkout-overlay {
  position: fixed; inset: 0; z-index: 100;
  display: grid; place-items: center;
  background: oklch(20% 0.02 260 / 0.45);
  -webkit-backdrop-filter: blur(8px); backdrop-filter: blur(8px);
}
#checkout-overlay[hidden] { display: none; }
.overlay-card {
  background: var(--glass-fill);
  border: 1px solid var(--glass-border);
  box-shadow: var(--glass-edge), 0 24px 60px -20px oklch(20% 0.03 260 / 0.5);
  -webkit-backdrop-filter: blur(32px) saturate(180%); backdrop-filter: blur(32px) saturate(180%);
  border-radius: var(--radius-lg);
  padding: 2rem 2.5rem;
  text-align: center;
  max-width: 22rem;
}
.overlay-card p:first-child { font-weight: 600; font-size: 1.05rem; }
.overlay-card .quiet { margin-top: 0.4rem; }

/* ───────────────────────── Motion / reveal ───────────────────────── */
@keyframes rise {
  from { opacity: 0; transform: translateY(14px); }
  to { opacity: 1; transform: translateY(0); }
}
.hero .eyebrow, .hero h1, .hero .lede, .hero .cta-row { animation: rise 600ms var(--ease) both; }
.hero .eyebrow { animation-delay: 40ms; }
.hero h1 { animation-delay: 100ms; }
.hero .lede { animation-delay: 180ms; }
.hero .cta-row { animation-delay: 260ms; }

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

/* ───────────────────────── Responsive ───────────────────────── */
@media (max-width: 640px) {
  .site-header nav { gap: 0.1rem; }
  .site-header nav a { padding: 0.35rem 0.5rem; font-size: 0.82rem; }
  .cta-row { flex-direction: column; align-items: stretch; }
  .cta { width: 100%; }
}