:root {
  --bg: #edf6f2;
  --bg-deep: #dcefe7;
  --paper: rgba(255, 255, 255, 0.9);
  --paper-strong: rgba(255, 255, 255, 0.97);
  --paper-soft: rgba(255, 255, 255, 0.72);
  --glass: rgba(255, 255, 255, 0.48);
  --glass-strong: rgba(255, 255, 255, 0.72);
  --glass-soft: rgba(255, 255, 255, 0.3);
  --ink: #132325;
  --ink-soft: #4f6668;
  --ink-quiet: #708486;
  --line: rgba(16, 57, 60, 0.12);
  --line-strong: rgba(16, 57, 60, 0.22);
  --accent: #0e5a5d;
  --accent-strong: #0a3d3f;
  --accent-soft: rgba(14, 90, 93, 0.1);
  --device-shell: linear-gradient(180deg, rgba(251, 255, 253, 0.92), rgba(241, 249, 245, 0.82));
  --card-reader: linear-gradient(180deg, rgba(255, 255, 255, 0.98), rgba(248, 251, 250, 0.92));
  --card-tinted: linear-gradient(180deg, rgba(247, 252, 250, 0.96), rgba(242, 248, 245, 0.9));
  --surface-contrast-bg: linear-gradient(180deg, rgba(14, 90, 93, 0.14), rgba(10, 61, 63, 0.18));
  --surface-contrast-border: rgba(14, 90, 93, 0.14);
  --surface-contrast-ink: #103235;
  --surface-contrast-muted: #456264;
  --shadow: 0 24px 56px rgba(17, 63, 58, 0.12);
  --shadow-soft: 0 12px 28px rgba(17, 63, 58, 0.08);
  --surface-dark: linear-gradient(180deg, rgba(18, 35, 42, 0.96), rgba(11, 23, 29, 0.98));
  --font-display: "Iowan Old Style", "Baskerville", "Times New Roman", "Songti SC", "STSong", serif;
  --font-body: "Avenir Next", "PingFang SC", "Noto Sans SC", "Helvetica Neue", sans-serif;
}

:root[data-theme="dark"] {
  --bg: #071417;
  --bg-deep: #0d2226;
  --paper: rgba(10, 24, 28, 0.86);
  --paper-strong: rgba(10, 20, 24, 0.96);
  --paper-soft: rgba(18, 36, 41, 0.78);
  --glass: rgba(8, 22, 27, 0.58);
  --glass-strong: rgba(18, 36, 41, 0.78);
  --glass-soft: rgba(12, 28, 33, 0.72);
  --ink: #eef7f4;
  --ink-soft: #a6c2bf;
  --ink-quiet: #7e9a98;
  --line: rgba(120, 215, 193, 0.16);
  --line-strong: rgba(120, 215, 193, 0.28);
  --accent: #75d8c3;
  --accent-strong: #b4fff0;
  --accent-soft: rgba(117, 216, 195, 0.14);
  --device-shell: linear-gradient(180deg, rgba(10, 22, 27, 0.96), rgba(8, 18, 23, 0.9));
  --card-reader: linear-gradient(180deg, rgba(16, 34, 40, 0.98), rgba(12, 24, 30, 0.94));
  --card-tinted: linear-gradient(180deg, rgba(13, 30, 35, 0.96), rgba(10, 22, 27, 0.92));
  --surface-contrast-bg: var(--surface-dark);
  --surface-contrast-border: rgba(255, 255, 255, 0.06);
  --surface-contrast-ink: #f3faf8;
  --surface-contrast-muted: rgba(243, 250, 248, 0.72);
  --shadow: 0 28px 60px rgba(0, 0, 0, 0.32);
  --shadow-soft: 0 14px 32px rgba(0, 0, 0, 0.22);
  --surface-dark: linear-gradient(180deg, rgba(7, 20, 24, 0.96), rgba(5, 14, 18, 0.98));
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-width: 320px;
  color: var(--ink);
  font-family: var(--font-body);
  background:
    radial-gradient(circle at top left, rgba(222, 243, 236, 0.86), transparent 34%),
    radial-gradient(circle at 90% 14%, rgba(187, 229, 219, 0.54), transparent 26%),
    linear-gradient(180deg, #f7fcfa 0%, var(--bg) 52%, #e6f3ee 100%);
}

:root[data-theme="dark"] body {
  background:
    radial-gradient(circle at top left, rgba(23, 83, 76, 0.38), transparent 34%),
    radial-gradient(circle at 90% 14%, rgba(37, 111, 101, 0.22), transparent 26%),
    linear-gradient(180deg, #071417 0%, #0b191d 48%, #0d1f24 100%);
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  opacity: 0.2;
  background-image:
    linear-gradient(rgba(16, 57, 60, 0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(16, 57, 60, 0.03) 1px, transparent 1px);
  background-size: 32px 32px;
}

a {
  color: inherit;
  text-decoration: none;
}

main,
section,
footer {
  scroll-margin-top: 104px;
}

.page-shell {
  width: min(1200px, calc(100vw - 24px));
  margin: 0 auto;
  padding: 14px 0 40px;
}

.surface,
.surface-subtle,
.surface-contrast,
.capability-card,
.privacy-card,
.assistant-copy,
.assistant-scene,
.cta-section,
.dl-btn {
  border: 1px solid var(--line);
  border-radius: 28px;
  background: linear-gradient(180deg, var(--paper-strong), var(--paper));
  box-shadow: var(--shadow-soft);
}

.surface-subtle {
  background: linear-gradient(180deg, var(--paper-soft), var(--paper));
}

.surface-contrast,
.hero-note-dark {
  background: var(--surface-contrast-bg);
  color: var(--surface-contrast-ink);
  border-color: var(--surface-contrast-border);
}

.topbar,
.hero,
.content-section,
.cta-section,
.site-footer {
  opacity: 0;
  transform: translateY(18px);
  animation: rise-in 700ms ease forwards;
}

.topbar {
  position: sticky;
  top: 12px;
  z-index: 30;
  display: grid;
  grid-template-columns: 1fr;
  grid-template-areas:
    "brand"
    "nav"
    "tools";
  gap: 12px;
  align-items: center;
  padding: 12px;
  border: 1px solid var(--line);
  border-radius: 24px;
  background: var(--paper-soft);
  backdrop-filter: blur(16px);
  box-shadow: 0 14px 32px rgba(29, 48, 45, 0.08);
}

.brand-lockup {
  grid-area: brand;
  display: inline-flex;
  align-items: center;
  gap: 12px;
  min-width: 0;
}

.brand-logo {
  width: 44px;
  height: 44px;
  border-radius: 15px;
  box-shadow: 0 10px 22px rgba(17, 35, 37, 0.14);
  object-fit: cover;
}

.brand-text {
  display: flex;
  flex-direction: column;
  gap: 1px;
  min-width: 0;
}

.brand-text strong {
  font-size: 1rem;
  line-height: 1.1;
}

.brand-text span {
  color: var(--ink-quiet);
  font-size: 0.8rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.topbar-tools {
  grid-area: tools;
  display: inline-flex;
  justify-content: flex-start;
}

.lang-switch {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--glass-soft);
}

.tool-chip {
  min-height: 34px;
  padding: 0 12px;
  border: 0;
  border-radius: 999px;
  background: transparent;
  color: var(--ink-soft);
  font: inherit;
  cursor: pointer;
  transition: transform 180ms ease, background-color 180ms ease, color 180ms ease;
}

.tool-chip.is-active {
  background: var(--accent);
  color: #f7f3ea;
}

.topnav {
  grid-area: nav;
  display: flex;
  gap: 10px;
  overflow-x: auto;
  padding-bottom: 2px;
  scrollbar-width: none;
}

.topnav::-webkit-scrollbar {
  display: none;
}

.topnav a {
  display: inline-flex;
  align-items: center;
  min-height: 38px;
  padding: 0 14px;
  border-radius: 999px;
  color: var(--ink-soft);
  background: var(--glass);
  border: 1px solid transparent;
  white-space: nowrap;
}

.hero {
  margin-top: 18px;
  display: grid;
  gap: 24px;
  padding: 28px;
}

.hero-copy {
  display: grid;
  gap: 18px;
}

.eyebrow,
.mini-label,
.capability-kicker,
.chat-label,
.visual-meta,
.page-badge,
.dl-badge {
  font-size: 0.75rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.eyebrow,
.page-badge,
.capability-kicker,
.mini-label {
  color: var(--accent);
}

.hero h1,
.section-heading h2,
.cta-section h2 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 600;
  line-height: 1.06;
  letter-spacing: 0;
}

.hero h1 {
  font-size: clamp(2.2rem, 5vw, 4.7rem);
  max-width: 11ch;
}

.hero-lead,
.section-heading,
.capability-card p,
.privacy-card p,
.assistant-copy li,
.assistant-scene p,
.download-note,
.site-footer p {
  color: var(--ink-soft);
  line-height: 1.65;
}

.hero-actions,
.assistant-actions,
.footer-links,
.proof-tags,
.format-pills,
.download-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.button,
.dl-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 18px;
  border-radius: 999px;
  font-weight: 600;
}

.button-primary {
  color: #f7f3ea;
  background: var(--accent);
}

.button-secondary {
  background: var(--glass);
  border: 1px solid var(--line);
}

.hero-visual {
  position: relative;
  display: grid;
  gap: 16px;
}

.hero-glow {
  position: absolute;
  inset: 10% 18% auto;
  height: 240px;
  border-radius: 999px;
  background: radial-gradient(circle, rgba(87, 164, 145, 0.28), transparent 70%);
  filter: blur(12px);
}

.phone-frame {
  position: relative;
  z-index: 1;
  border-radius: 34px;
  padding: 16px;
  background: var(--device-shell);
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
}

.phone-chrome,
.visual-card-top,
.capability-head,
.dl-copy {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.phone-dots {
  display: inline-flex;
  gap: 8px;
}

.phone-dots span {
  width: 9px;
  height: 9px;
  border-radius: 999px;
  background: rgba(14, 90, 93, 0.24);
}

.device-chip {
  display: inline-flex;
  align-items: center;
  min-height: 30px;
  padding: 0 10px;
  border-radius: 999px;
  background: rgba(14, 90, 93, 0.08);
  color: var(--accent);
  font-size: 0.76rem;
}

.phone-stack {
  display: grid;
  gap: 14px;
  margin-top: 16px;
}

.visual-card,
.hero-note,
.privacy-highlight,
.privacy-card,
.capability-card,
.assistant-copy,
.assistant-scene,
.cta-section,
.site-footer {
  padding: 20px;
}

.visual-card {
  border-radius: 22px;
  border: 1px solid var(--line);
}

.visual-card-reader {
  background: var(--card-reader);
}

.visual-card-formats,
.visual-card-chat {
  background: var(--card-tinted);
}

.visual-card h2,
.capability-card h3,
.privacy-highlight h3,
.privacy-card h3 {
  margin: 0;
  letter-spacing: 0;
}

.page-lines {
  display: grid;
  gap: 10px;
  margin-top: 18px;
}

.page-lines span {
  display: block;
  height: 9px;
  border-radius: 999px;
  background: linear-gradient(90deg, rgba(14, 90, 93, 0.18), rgba(14, 90, 93, 0.04));
}

.page-lines span:nth-child(2) {
  width: 88%;
}

.page-lines span:nth-child(3) {
  width: 70%;
}

.format-pills span,
.proof-tags span,
.assistant-actions span {
  display: inline-flex;
  align-items: center;
  min-height: 32px;
  padding: 0 12px;
  border-radius: 999px;
  background: var(--glass);
  border: 1px solid var(--line);
}

.chat-row {
  display: grid;
  gap: 8px;
  padding: 14px;
  border-radius: 18px;
}

.chat-row-user {
  background: rgba(14, 90, 93, 0.08);
}

.chat-row-assistant {
  margin-top: 10px;
  background: rgba(255, 255, 255, 0.42);
}

.hero-sidecards {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.content-section {
  display: grid;
  gap: 22px;
  margin-top: 18px;
}

.section-heading {
  display: grid;
  gap: 10px;
  max-width: 760px;
}

.section-heading h2 {
  font-size: clamp(1.8rem, 3vw, 3rem);
}

.capability-grid,
.privacy-grid {
  display: grid;
  gap: 14px;
}

.capability-index {
  font-size: 0.88rem;
  color: var(--ink-quiet);
}

.privacy-shell,
.assistant-layout {
  display: grid;
  gap: 14px;
}

.assistant-points {
  margin: 0;
  padding-left: 18px;
}

.assistant-points li + li {
  margin-top: 10px;
}

.source-panel blockquote {
  margin: 10px 0 14px;
  padding-left: 14px;
  border-left: 3px solid rgba(14, 90, 93, 0.22);
  font-family: var(--font-display);
  font-size: 1.1rem;
  line-height: 1.7;
}

.download-grid {
  gap: 14px;
}

.dl-btn {
  flex: 1 1 260px;
  justify-content: flex-start;
  gap: 14px;
  padding: 16px 18px;
  border-radius: 24px;
}

.dl-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 42px;
  height: 42px;
  border-radius: 14px;
  background: rgba(14, 90, 93, 0.08);
  color: var(--accent);
}

.dl-icon svg {
  width: 22px;
  height: 22px;
}

.dl-copy {
  flex: 1 1 auto;
  align-items: flex-start;
  flex-direction: column;
}

.dl-platform {
  font-weight: 700;
}

.dl-desc,
.chat-label,
.visual-meta,
.download-note,
.site-footer,
.footer-links a {
  color: var(--ink-soft);
}

.cta-section {
  margin-top: 18px;
  display: grid;
  gap: 16px;
}

.site-footer {
  margin-top: 18px;
  display: grid;
  gap: 16px;
}

.footer-links a {
  min-height: 32px;
  display: inline-flex;
  align-items: center;
}

@keyframes rise-in {
  from {
    opacity: 0;
    transform: translateY(18px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (min-width: 820px) {
  .topbar {
    grid-template-columns: auto 1fr auto;
    grid-template-areas: "brand nav tools";
  }

  .topbar-tools {
    justify-content: flex-end;
  }

  .hero {
    grid-template-columns: minmax(0, 1.02fr) minmax(0, 0.98fr);
    align-items: center;
  }

  .capability-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .privacy-shell {
    grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
  }

  .assistant-layout {
    grid-template-columns: minmax(0, 0.92fr) minmax(0, 1.08fr);
  }

  .site-footer {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: start;
  }
}

@media (max-width: 819px) {
  .hero {
    padding: 22px;
  }

  .hero-sidecards {
    grid-template-columns: 1fr;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  .topbar,
  .hero,
  .content-section,
  .cta-section,
  .site-footer {
    animation: none;
    opacity: 1;
    transform: none;
  }
}