:root {
  --canvas: #f5f1ec;
  --surface: #ffffff;
  --surface-2: #ebe7e1;
  --ink: #111111;
  --ink-muted: #626260;
  --ink-subtle: #7b7b78;
  --ink-tertiary: #9c9fa5;
  --hairline: #d3cec6;
  --hairline-soft: #ebe7e1;
  --brand: #2563eb;
  --brand-hover: #1d4ed8;
  --brand-soft: #e8eeff;
  --on-primary: #ffffff;
  --success: #16a34a;
  --font: Inter, "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --radius-sm: 6px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --max: 1120px;
  --nav-h: 64px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 80px; }
html, body { margin: 0; padding: 0; }
body {
  font-family: var(--font);
  background: var(--canvas);
  color: var(--ink);
  font-size: 16px;
  line-height: 1.5;
  font-weight: 400;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
button, input, textarea { font-family: inherit; }

.wrap {
  width: min(var(--max), calc(100% - 48px));
  margin: 0 auto;
}

/* Nav */
.nav {
  position: sticky;
  top: 0;
  z-index: 40;
  height: var(--nav-h);
  background: color-mix(in srgb, var(--canvas) 88%, transparent);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--hairline);
}
.nav-inner {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}
.brand-mark {
  width: 28px;
  height: 28px;
  overflow: hidden;
  flex-shrink: 0;
}
.brand-mark img {
  width: 28px;
  height: auto;
  display: block;
}
.brand-name {
  font-size: 16px;
  font-weight: 600;
  letter-spacing: -0.02em;
}
.nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
}
.nav-links a {
  padding: 8px 12px;
  border-radius: var(--radius-md);
  font-size: 14px;
  color: var(--ink-muted);
}
.nav-links a:hover,
.nav-links a.is-active {
  color: var(--ink);
  background: var(--surface);
}
.nav-actions { display: flex; align-items: center; gap: 8px; }
.nav-toggle {
  display: none;
  width: 40px;
  height: 40px;
  border: 1px solid var(--hairline);
  background: var(--surface);
  border-radius: var(--radius-md);
  cursor: pointer;
}
.nav-toggle span,
.nav-toggle span::before,
.nav-toggle span::after {
  display: block;
  width: 16px;
  height: 1.5px;
  background: var(--ink);
  position: relative;
  margin: 0 auto;
}
.nav-toggle span::before,
.nav-toggle span::after {
  content: "";
  position: absolute;
  left: 0;
}
.nav-toggle span::before { top: -5px; }
.nav-toggle span::after { top: 5px; }

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 40px;
  padding: 10px 16px;
  border-radius: 6px;
  font-size: 14px;
  font-weight: 500;
  line-height: 1.2;
  border: 1px solid transparent;
  cursor: pointer;
  transition: background .15s ease, color .15s ease, border-color .15s ease;
}
.btn-primary {
  background: var(--ink);
  color: var(--on-primary);
}
.btn-primary:hover { background: #000; }
.btn-secondary {
  background: var(--surface);
  color: var(--ink);
  border-color: var(--hairline);
}
.btn-secondary:hover { background: var(--surface-2); }
.btn-brand {
  background: var(--brand);
  color: #fff;
}
.btn-brand:hover { background: var(--brand-hover); }

/* Hero */
.hero {
  padding: 80px 0 40px;
  overflow: hidden;
}
.hero-grid {
  display: grid;
  grid-template-columns: 1fr 1.05fr;
  gap: 32px;
  align-items: center;
}
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  font-weight: 500;
  color: var(--ink-muted);
  margin-bottom: 18px;
}
.eyebrow::before {
  content: "";
  width: 8px;
  height: 8px;
  border-radius: 99px;
  background: var(--brand);
}
.hero h1 {
  margin: 0 0 18px;
  font-size: clamp(36px, 5vw, 64px);
  font-weight: 500;
  line-height: 1.12;
  letter-spacing: -0.03em;
}
.hero-lead {
  margin: 0 0 32px;
  max-width: 34em;
  font-size: 18px;
  line-height: 1.6;
  color: var(--ink-muted);
}
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; }

.download-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}
.download-card {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 12px;
}
.download-card h3 { margin: 0; }
.download-card p { margin: 0; color: var(--ink-muted); }
.download-card code {
  font-size: 13px;
  background: var(--surface-2);
  padding: 1px 6px;
  border-radius: 4px;
}
.download-qr {
  display: inline-flex;
  margin-top: 4px;
  padding: 8px;
  background: #fff;
  border: 1px solid var(--hairline);
  border-radius: 12px;
}
.download-qr img { display: block; width: 164px; height: 164px; }
.download-note {
  margin: 0;
  font-size: 13px;
  color: var(--ink-subtle);
}
#androidDownload.is-missing {
  opacity: 0.55;
  cursor: not-allowed;
}
.hero-meta {
  display: flex;
  gap: 24px;
  margin-top: 36px;
  padding-top: 24px;
  border-top: 1px solid var(--hairline);
}
.hero-meta b {
  display: block;
  font-size: 20px;
  font-weight: 600;
  letter-spacing: -0.03em;
}
.hero-meta span {
  font-size: 13px;
  color: var(--ink-subtle);
}

.cover {
  --cover-w: 228px;
  position: relative;
  height: 500px;
  perspective: 1400px;
  touch-action: pan-y;
  user-select: none;
  cursor: grab;
}
.cover:active { cursor: grabbing; }
.cover-item {
  position: absolute;
  left: 50%;
  top: 50%;
  width: var(--cover-w);
  padding: 0;
  border: 0;
  background: none;
  transform: translate(-50%, -50%) scale(.72);
  opacity: 0;
  pointer-events: none;
  z-index: 0;
  transition: transform .45s cubic-bezier(.22, 1, .36, 1), opacity .35s ease;
  filter: drop-shadow(0 16px 28px rgba(17, 17, 17, .14));
}
.cover-item img {
  width: 100%;
  height: auto;
  display: block;
  pointer-events: none;
}
.cover-item[data-pos="-1"],
.cover-item[data-pos="0"],
.cover-item[data-pos="1"] {
  opacity: 1;
  pointer-events: auto;
}
.cover-item[data-pos="0"] {
  transform: translate(-50%, -50%) scale(1);
  z-index: 3;
  cursor: default;
}
.cover-item[data-pos="-1"] {
  transform: translate(-50%, -50%) translateX(-176px) rotateY(8deg) scale(.78);
  z-index: 2;
  cursor: pointer;
}
.cover-item[data-pos="1"] {
  transform: translate(-50%, -50%) translateX(176px) rotateY(-8deg) scale(.78);
  z-index: 2;
  cursor: pointer;
}
.cover-item[data-pos="-2"] {
  transform: translate(-50%, -50%) translateX(-248px) rotateY(12deg) scale(.62);
}
.cover-item[data-pos="2"] {
  transform: translate(-50%, -50%) translateX(248px) rotateY(-12deg) scale(.62);
}

/* Product mock */
.product-card {
  background: var(--surface);
  border: 1px solid var(--hairline);
  border-radius: var(--radius-xl);
  overflow: hidden;
}
.product-chrome {
  display: flex;
  align-items: center;
  gap: 10px;
  height: 44px;
  padding: 0 16px;
  border-bottom: 1px solid var(--hairline-soft);
  background: #fbfaf8;
}
.dots { display: flex; gap: 6px; }
.dots i {
  width: 8px;
  height: 8px;
  border-radius: 99px;
  background: #d9d4cc;
}
.product-chrome p {
  margin: 0;
  font-size: 13px;
  color: var(--ink-subtle);
}
.product-body {
  display: grid;
  grid-template-columns: 200px 1fr;
  min-height: 440px;
}
.conv-list {
  border-right: 1px solid var(--hairline-soft);
  padding: 12px;
  background: #fcfbf9;
}
.conv-search {
  height: 34px;
  border-radius: 8px;
  background: var(--surface-2);
  color: var(--ink-tertiary);
  font-size: 12px;
  display: flex;
  align-items: center;
  padding: 0 10px;
  margin-bottom: 10px;
}
.conv {
  display: flex;
  gap: 10px;
  padding: 10px;
  border-radius: 10px;
}
.conv.is-active { background: var(--surface); border: 1px solid var(--hairline-soft); }
.avatar {
  width: 32px;
  height: 32px;
  border-radius: 99px;
  display: grid;
  place-items: center;
  font-size: 12px;
  font-weight: 600;
  color: #fff;
  flex-shrink: 0;
}
.conv strong { display: block; font-size: 13px; font-weight: 500; }
.conv em {
  display: block;
  font-style: normal;
  font-size: 12px;
  color: var(--ink-subtle);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.chat-pane { display: flex; flex-direction: column; min-width: 0; }
.chat-head {
  height: 52px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 16px;
  border-bottom: 1px solid var(--hairline-soft);
}
.chat-head strong { font-size: 14px; font-weight: 500; }
.chat-head span { font-size: 12px; color: var(--success); }
.chat-thread {
  flex: 1;
  padding: 18px 16px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.bubble {
  max-width: 82%;
  padding: 10px 12px;
  border-radius: 12px;
  font-size: 13px;
  line-height: 1.45;
}
.bubble small {
  display: block;
  margin-top: 4px;
  font-size: 11px;
  color: var(--ink-tertiary);
}
.bubble.in {
  background: var(--surface-2);
  align-self: flex-start;
}
.bubble.out {
  background: var(--brand);
  color: #fff;
  align-self: flex-end;
}
.bubble.out small { color: rgba(255,255,255,.7); }
.chip {
  align-self: center;
  font-size: 11px;
  color: var(--ink-tertiary);
  background: var(--surface-2);
  padding: 3px 8px;
  border-radius: 99px;
}
.chat-input {
  margin: 0 16px 16px;
  height: 44px;
  border: 1px solid var(--hairline);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 8px 0 14px;
  color: var(--ink-tertiary);
  font-size: 13px;
}
.send {
  width: 28px;
  height: 28px;
  border-radius: 8px;
  background: var(--ink);
  color: #fff;
  display: grid;
  place-items: center;
  font-size: 12px;
}

/* Sections */
.section { padding: 96px 0; }
.section-head {
  max-width: 640px;
  margin-bottom: 40px;
}
.section-head.center {
  text-align: center;
  margin-left: auto;
  margin-right: auto;
}
.section h2 {
  margin: 0 0 12px;
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 500;
  letter-spacing: -0.03em;
  line-height: 1.2;
}
.section-head p {
  margin: 0;
  font-size: 18px;
  color: var(--ink-muted);
}

.grid-3, .grid-6, .grid-2 {
  display: grid;
  gap: 16px;
}
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-6 { grid-template-columns: repeat(3, 1fr); }
.grid-2 { grid-template-columns: 1fr 1fr; }

.card {
  background: var(--surface);
  border: 1px solid var(--hairline);
  border-radius: var(--radius-lg);
  padding: 24px;
  box-shadow: inset 0 1px 0 rgba(255,255,255,.7);
  transition: border-color .15s ease;
}
.card:hover { border-color: #c4bfb6; }
.card h3 {
  margin: 14px 0 8px;
  font-size: 20px;
  font-weight: 500;
  letter-spacing: -0.02em;
}
.card p {
  margin: 0;
  font-size: 14px;
  color: var(--ink-muted);
  line-height: 1.55;
}
.ico {
  width: 40px;
  height: 40px;
  border-radius: 10px;
  background: var(--brand-soft);
  color: var(--brand);
  display: grid;
  place-items: center;
}
.ico svg { width: 20px; height: 20px; }

.scene {
  min-height: 196px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}
.scene-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.scene .tag {
  font-size: 12px;
  font-weight: 500;
  color: var(--brand);
}
.scene .idx {
  font-size: 12px;
  color: var(--ink-tertiary);
}

.process {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}
.step {
  background: var(--surface);
  border: 1px solid var(--hairline);
  border-radius: var(--radius-lg);
  padding: 24px;
  min-height: 180px;
}
.step-num {
  font-size: 13px;
  font-weight: 500;
  color: var(--brand);
  margin-bottom: 18px;
}
.step h3 {
  margin: 0 0 8px;
  font-size: 20px;
  font-weight: 500;
}
.step p {
  margin: 0;
  font-size: 14px;
  color: var(--ink-muted);
}

.cta-banner {
  background: var(--ink);
  color: #fff;
  border-radius: var(--radius-lg);
  padding: 48px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}
.cta-banner h2 {
  margin: 0 0 8px;
  font-size: 28px;
  font-weight: 500;
  letter-spacing: -0.03em;
  color: #fff;
}
.cta-banner p {
  margin: 0;
  color: #9c9fa5;
}
.cta-banner .btn-primary {
  background: #fff;
  color: #111;
}
.cta-banner .btn-primary:hover { background: #f3f3f3; }

/* Footer */
.footer {
  padding: 64px 0 32px;
  border-top: 1px solid var(--hairline);
  color: var(--ink-muted);
  font-size: 13px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: 32px;
  margin-bottom: 48px;
}
.footer strong {
  display: block;
  color: var(--ink);
  font-size: 14px;
  font-weight: 500;
  margin-bottom: 14px;
}
.footer a {
  display: block;
  padding: 5px 0;
  color: var(--ink-subtle);
}
.footer a:hover { color: var(--ink); }
.footer-copy {
  padding-top: 24px;
  border-top: 1px solid var(--hairline-soft);
  color: var(--ink-tertiary);
}

/* Contact dock */
.dock {
  position: fixed;
  right: 16px;
  bottom: 24px;
  z-index: 30;
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.dock-btn {
  width: 48px;
  height: 48px;
  border: 1px solid var(--hairline);
  background: var(--surface);
  border-radius: var(--radius-md);
  display: grid;
  place-items: center;
  cursor: pointer;
  position: relative;
}
.dock-btn:hover { background: var(--surface-2); }
.dock-pop {
  position: absolute;
  right: calc(100% + 10px);
  top: 50%;
  transform: translateY(-50%);
  background: var(--surface);
  border: 1px solid var(--hairline);
  border-radius: var(--radius-md);
  padding: 12px 14px;
  white-space: nowrap;
  font-size: 13px;
  color: var(--ink);
  display: none;
  min-width: 160px;
}
.dock-btn:hover .dock-pop,
.dock-btn:focus-within .dock-pop { display: block; }
.dock-pop b { display: block; font-size: 12px; color: var(--ink-subtle); font-weight: 500; margin-bottom: 4px; }

/* Inner pages */
.page {
  padding: 56px 0 96px;
}
.page-head {
  max-width: 720px;
  margin-bottom: 40px;
}
.page-head h1 {
  margin: 0 0 10px;
  font-size: clamp(32px, 5vw, 48px);
  font-weight: 500;
  letter-spacing: -0.03em;
}
.page-head p { margin: 0; color: var(--ink-muted); }

.policy {
  max-width: 760px;
  background: var(--surface);
  border: 1px solid var(--hairline);
  border-radius: var(--radius-xl);
  padding: 40px 44px;
}
.policy h1 { font-size: 32px; font-weight: 500; letter-spacing: -0.03em; margin: 0 0 8px; }
.policy h2 {
  font-size: 22px;
  font-weight: 500;
  margin: 36px 0 12px;
  letter-spacing: -0.02em;
}
.policy h4 {
  margin: 0 0 4px;
  font-size: 14px;
  font-weight: 500;
  color: var(--ink-muted);
}
.policy p, .policy li {
  color: var(--ink-muted);
  font-size: 15px;
  line-height: 1.75;
}
.policy ul { padding-left: 18px; }

.board {
  display: grid;
  grid-template-columns: 1.1fr .9fr;
  gap: 20px;
  align-items: start;
}
.board-card { padding: 28px; }
.comment-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.comment-list li {
  background: var(--surface-2);
  border-radius: 10px;
  padding: 12px 14px;
  font-size: 14px;
  color: var(--ink);
  word-break: break-word;
}
.comment-empty {
  color: var(--ink-subtle);
  font-size: 14px;
}
.field { display: flex; flex-direction: column; gap: 8px; margin-bottom: 16px; }
.field label { font-size: 14px; font-weight: 500; }
.field textarea,
.field input {
  width: 100%;
  border: 1px solid var(--hairline);
  background: var(--surface);
  border-radius: var(--radius-md);
  padding: 12px 14px;
  font-size: 15px;
  color: var(--ink);
  resize: vertical;
  min-height: 120px;
}
.field textarea:focus,
.field input:focus {
  outline: 2px solid color-mix(in srgb, var(--brand) 45%, transparent);
  border-color: var(--brand);
}
.form-note { font-size: 13px; color: var(--ink-subtle); margin: 0 0 16px; }

.notfound {
  min-height: calc(100vh - 220px);
  display: grid;
  place-items: center;
  text-align: center;
  padding: 80px 24px;
}
.notfound h1 {
  font-size: 72px;
  font-weight: 500;
  letter-spacing: -0.04em;
  margin: 0 0 8px;
}
.notfound p { color: var(--ink-muted); margin: 0 0 24px; }

@media (max-width: 1024px) {
  .hero-grid, .board, .footer-grid { grid-template-columns: 1fr; }
  .grid-3, .grid-6, .process { grid-template-columns: 1fr 1fr; }
  .product-body { grid-template-columns: 180px 1fr; }
  .cover { --cover-w: 200px; height: 460px; }
}

@media (max-width: 768px) {
  .wrap { width: calc(100% - 32px); }
  .nav-links, .nav-actions .btn-secondary { display: none; }
  .nav.is-open .nav-links {
    display: flex;
    flex-direction: column;
    position: absolute;
    left: 0;
    right: 0;
    top: var(--nav-h);
    background: var(--canvas);
    border-bottom: 1px solid var(--hairline);
    padding: 12px 16px 16px;
  }
  .nav-toggle { display: grid; place-items: center; }
  .hero { padding: 40px 0 24px; }
  .hero-grid { gap: 28px; }
  .product-body { grid-template-columns: 1fr; }
  .conv-list { display: none; }
  .cover { --cover-w: 168px; height: 400px; }
  .cover-item[data-pos="-1"] { transform: translate(-50%, -50%) translateX(-118px) rotateY(6deg) scale(.78); }
  .cover-item[data-pos="1"] { transform: translate(-50%, -50%) translateX(118px) rotateY(-6deg) scale(.78); }
  .grid-3, .grid-6, .process, .grid-2, .download-grid { grid-template-columns: 1fr; }
  .section { padding: 64px 0; }
  .cta-banner { flex-direction: column; align-items: flex-start; padding: 28px; }
  .policy { padding: 24px 20px; }
  .dock { flex-direction: row; }
  body { padding-bottom: 72px; }
  .hero-meta { padding-right: 0; }
  .nav-actions .btn { display: none; }
}