/* 壶天信使官网的响应式水墨主题与下载交互样式。 */
:root {
  color-scheme: light dark;
  --paper: #f3efe5;
  --paper-deep: #e8e1d3;
  --card: #fbf9f3;
  --ink: #18201e;
  --ink-soft: #59635f;
  --ink-faint: #7b827e;
  --line: rgba(24, 32, 30, 0.13);
  --line-strong: rgba(24, 32, 30, 0.24);
  --vermilion: #bd3e3a;
  --vermilion-dark: #94312f;
  --gold: #aa8b46;
  --mist: rgba(255, 255, 255, 0.56);
  --shadow: 0 24px 70px rgba(39, 48, 44, 0.12);
  --shell: min(1120px, calc(100vw - 40px));
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: "Noto Serif SC", "Songti SC", "PingFang SC", serif;
  font-size: 16px;
  line-height: 1.75;
  text-rendering: optimizeLegibility;
}

body::before {
  position: fixed;
  inset: 0;
  z-index: -1;
  content: "";
  pointer-events: none;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 400 400' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.8' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
  opacity: 0.035;
  mix-blend-mode: multiply;
}

a {
  color: inherit;
}

img {
  display: block;
  max-width: 100%;
}

.skip-link {
  position: fixed;
  top: 12px;
  left: 12px;
  z-index: 100;
  padding: 8px 12px;
  background: var(--ink);
  color: var(--paper);
  transform: translateY(-150%);
}

.skip-link:focus {
  transform: translateY(0);
}

.shell {
  width: var(--shell);
  margin-inline: auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  border-bottom: 1px solid var(--line);
  background: color-mix(in srgb, var(--paper) 88%, transparent);
  backdrop-filter: blur(18px);
}

.nav-shell {
  display: flex;
  min-height: 74px;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  text-decoration: none;
}

.brand img {
  border-radius: 10px;
  box-shadow: 0 7px 18px rgba(16, 79, 122, 0.16);
}

.brand span {
  display: grid;
  line-height: 1.15;
}

.brand strong {
  font-size: 1rem;
  letter-spacing: 0.08em;
}

.brand small {
  margin-top: 4px;
  color: var(--ink-faint);
  font-family: ui-sans-serif, system-ui, sans-serif;
  font-size: 0.62rem;
  letter-spacing: 0.18em;
}

.nav-download {
  border-bottom: 1px solid var(--vermilion);
  color: var(--vermilion);
  font-weight: 700;
  text-decoration: none;
}

.nav-download:hover {
  color: var(--vermilion-dark);
}

.hero {
  position: relative;
  overflow: hidden;
  padding: clamp(68px, 9vw, 120px) 0 clamp(88px, 11vw, 140px);
}

.section-watermark::before {
  position: absolute;
  right: -0.05em;
  bottom: -0.44em;
  content: "信";
  color: var(--ink);
  font-family: "ZCOOL KuaiLe", cursive;
  font-size: min(42vw, 620px);
  line-height: 1;
  opacity: 0.025;
  pointer-events: none;
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.02fr) minmax(380px, 0.98fr);
  align-items: center;
  gap: clamp(40px, 8vw, 96px);
}

.eyebrow,
.section-kicker {
  margin: 0 0 18px;
  color: var(--vermilion);
  font-family: ui-sans-serif, system-ui, sans-serif;
  font-size: 0.76rem;
  font-weight: 800;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.eyebrow {
  display: flex;
  align-items: center;
  gap: 10px;
}

.eyebrow span {
  display: inline-block;
  width: 30px;
  height: 2px;
  background: var(--vermilion);
}

h1,
h2,
h3,
p {
  text-wrap: pretty;
}

h1,
h2 {
  margin: 0;
  font-family: "Noto Serif SC", serif;
  font-weight: 900;
  line-height: 1.18;
  letter-spacing: -0.035em;
}

h1 {
  max-width: 10em;
  font-size: clamp(3rem, 6.4vw, 6.3rem);
}

h1 em {
  color: var(--vermilion);
  font-style: normal;
}

h2 {
  font-size: clamp(2rem, 4.2vw, 3.7rem);
}

.hero-lead {
  max-width: 38rem;
  margin: 28px 0 0;
  color: var(--ink-soft);
  font-size: clamp(1.02rem, 1.5vw, 1.2rem);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 34px;
}

.button {
  display: inline-flex;
  min-height: 52px;
  align-items: center;
  justify-content: center;
  gap: 9px;
  padding: 12px 22px;
  border: 1px solid transparent;
  font-family: ui-sans-serif, system-ui, sans-serif;
  font-weight: 750;
  line-height: 1.2;
  text-align: center;
  text-decoration: none;
  transition: transform 160ms ease, box-shadow 160ms ease, background-color 160ms ease;
}

.button:hover {
  transform: translateY(-2px);
}

.button:focus-visible,
.nav-download:focus-visible,
.brand:focus-visible {
  outline: 3px solid color-mix(in srgb, var(--vermilion) 65%, transparent);
  outline-offset: 4px;
}

.button-primary {
  background: var(--vermilion);
  color: #fffaf0;
  box-shadow: 0 14px 34px rgba(189, 62, 58, 0.24);
}

.button-primary:hover {
  background: var(--vermilion-dark);
}

.button-quiet {
  border-color: var(--line-strong);
  background: var(--mist);
  color: var(--ink);
}

.download-facts {
  display: flex;
  flex-wrap: wrap;
  gap: 7px 22px;
  margin: 20px 0 0;
  padding: 0;
  color: var(--ink-faint);
  font-family: ui-sans-serif, system-ui, sans-serif;
  font-size: 0.8rem;
  list-style: none;
}

.download-facts li:not(:first-child)::before {
  margin-right: 20px;
  color: var(--gold);
  content: "·";
}

.signal-illustration {
  position: relative;
  min-height: 520px;
}

.phone-card {
  position: absolute;
  top: 20px;
  right: 38px;
  z-index: 3;
  width: min(286px, 72vw);
  min-height: 492px;
  padding: 18px 18px 24px;
  border: 1px solid rgba(24, 32, 30, 0.18);
  border-radius: 36px;
  background: color-mix(in srgb, var(--card) 95%, transparent);
  box-shadow: var(--shadow);
}

.phone-card::before {
  position: absolute;
  inset: 8px;
  border: 1px solid var(--line);
  border-radius: 29px;
  content: "";
  pointer-events: none;
}

.phone-top {
  position: relative;
  z-index: 1;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 2px 8px 16px;
  color: var(--ink-faint);
  font-family: ui-sans-serif, system-ui, sans-serif;
  font-size: 0.64rem;
}

.phone-top span {
  width: 58px;
  height: 5px;
  border-radius: 999px;
  background: var(--ink);
  opacity: 0.9;
}

.phone-brand {
  position: relative;
  z-index: 1;
  display: flex;
  align-items: center;
  gap: 11px;
  padding: 17px 10px 22px;
  border-top: 1px solid var(--line);
}

.phone-brand img {
  border-radius: 8px;
}

.phone-brand span,
.notice-row span {
  display: grid;
}

.phone-brand strong {
  font-size: 0.92rem;
}

.phone-brand small,
.notice-row small {
  color: var(--ink-faint);
  font-family: ui-sans-serif, system-ui, sans-serif;
  font-size: 0.66rem;
}

.notice-row {
  position: relative;
  z-index: 1;
  display: flex;
  align-items: flex-start;
  gap: 10px;
  margin: 0 8px 10px;
  padding: 13px 12px;
  border: 1px solid var(--line);
  background: var(--paper);
}

.notice-row i {
  flex: 0 0 auto;
  width: 7px;
  height: 7px;
  margin-top: 8px;
  border-radius: 50%;
  background: var(--vermilion);
}

.notice-row strong {
  font-size: 0.78rem;
}

.notice-row.muted i {
  background: var(--gold);
}

.source {
  position: absolute;
  z-index: 2;
  display: grid;
  min-width: 152px;
  padding: 18px;
  border-left: 3px solid var(--vermilion);
  background: var(--card);
  box-shadow: 0 16px 35px rgba(34, 44, 40, 0.1);
}

.source-desktop {
  top: 118px;
  left: 0;
}

.source-server {
  bottom: 76px;
  left: 14px;
}

.source-icon {
  color: var(--vermilion);
  font-family: ui-sans-serif, system-ui, sans-serif;
  font-size: 1.35rem;
  line-height: 1;
}

.source strong {
  margin-top: 9px;
  font-size: 0.82rem;
}

.source small {
  color: var(--ink-faint);
  font-family: ui-sans-serif, system-ui, sans-serif;
  font-size: 0.68rem;
}

.signal-line {
  position: absolute;
  z-index: 1;
  height: 1px;
  border-top: 1px dashed color-mix(in srgb, var(--vermilion) 60%, transparent);
  transform-origin: left center;
}

.signal-one {
  top: 190px;
  left: 134px;
  width: 155px;
  transform: rotate(-9deg);
}

.signal-two {
  bottom: 160px;
  left: 142px;
  width: 140px;
  transform: rotate(12deg);
}

.vertical-inscription {
  position: absolute;
  top: 30px;
  right: 0;
  margin: 0;
  color: var(--ink);
  font-family: "ZCOOL KuaiLe", cursive;
  letter-spacing: 0.22em;
  opacity: 0.2;
  writing-mode: vertical-rl;
}

.capabilities,
.boundary-section {
  position: relative;
  overflow: hidden;
  padding: clamp(84px, 11vw, 140px) 0;
  background: var(--paper-deep);
}

.capabilities::before {
  right: auto;
  left: -0.08em;
  content: "知";
}

.section-heading {
  max-width: 720px;
  margin-bottom: 48px;
}

.section-heading h2 {
  position: relative;
  display: inline-block;
}

.section-heading h2::after {
  display: block;
  width: 1.4em;
  height: 3px;
  margin-top: 17px;
  background: var(--vermilion);
  content: "";
}

.section-heading > p:last-child {
  max-width: 42rem;
  margin: 24px 0 0;
  color: var(--ink-soft);
}

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

.feature-card {
  position: relative;
  min-height: 278px;
  overflow: hidden;
  padding: 32px;
  border: 1px solid var(--line);
  background: var(--card);
  transition: transform 180ms ease, box-shadow 180ms ease;
}

.feature-card::before {
  position: absolute;
  top: 0;
  left: 0;
  width: 3px;
  height: 0;
  background: var(--vermilion);
  content: "";
  transition: height 220ms ease;
}

.feature-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 16px 40px rgba(26, 32, 30, 0.08);
}

.feature-card:hover::before {
  height: 100%;
}

.feature-number {
  color: var(--vermilion);
  font-family: "ZCOOL KuaiLe", cursive;
  font-size: 1.4rem;
}

.feature-card h3 {
  margin: 48px 0 12px;
  font-size: 1.25rem;
}

.feature-card p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 0.94rem;
}

.flow-section {
  padding: clamp(84px, 11vw, 140px) 0;
}

.flow-grid {
  display: grid;
  grid-template-columns: minmax(0, 0.75fr) minmax(0, 1.25fr);
  gap: clamp(40px, 8vw, 100px);
}

.section-heading.compact {
  margin: 0;
}

.flow-list {
  margin: 0;
  padding: 0;
  list-style: none;
}

.flow-list li {
  display: grid;
  grid-template-columns: 58px 1fr;
  gap: 20px;
  padding: 24px 0;
  border-top: 1px solid var(--line);
}

.flow-list li:last-child {
  border-bottom: 1px solid var(--line);
}

.flow-list > li > span {
  color: var(--vermilion);
  font-family: ui-sans-serif, system-ui, sans-serif;
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.1em;
}

.flow-list strong {
  font-size: 1.04rem;
}

.flow-list p {
  margin: 6px 0 0;
  color: var(--ink-soft);
  font-size: 0.92rem;
}

.release-section {
  position: relative;
  overflow: hidden;
  padding: clamp(78px, 10vw, 120px) 0;
  background: #171b1a;
  color: #f5f1e8;
}

.release-section::before {
  position: absolute;
  right: -4vw;
  bottom: -0.55em;
  color: #fff;
  content: "达";
  font-family: "ZCOOL KuaiLe", cursive;
  font-size: min(42vw, 600px);
  line-height: 1;
  opacity: 0.025;
}

.release-grid {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(300px, 0.85fr);
  align-items: end;
  gap: 56px 80px;
}

.section-kicker.light {
  color: #d99b76;
}

.release-lead {
  max-width: 42rem;
  margin: 24px 0 0;
  color: #d4d8d5;
}

.release-note {
  max-width: 42rem;
  margin: 18px 0 0;
  padding-left: 16px;
  border-left: 2px solid #bd6d66;
  color: #b8c0bc;
  font-size: 0.9rem;
}

.release-meta {
  margin: 0;
  border-top: 1px solid rgba(255, 255, 255, 0.16);
}

.release-meta div {
  display: grid;
  grid-template-columns: 7.5em 1fr;
  gap: 16px;
  padding: 13px 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.12);
}

.release-meta dt {
  color: #9da7a2;
  font-family: ui-sans-serif, system-ui, sans-serif;
  font-size: 0.78rem;
}

.release-meta dd {
  margin: 0;
  color: #f5f1e8;
  font-family: ui-sans-serif, system-ui, sans-serif;
  font-size: 0.82rem;
  word-break: break-word;
}

.release-meta .checksum {
  grid-template-columns: 1fr;
  gap: 4px;
}

.checksum dd {
  color: #c9d0cc;
  font-family: ui-monospace, SFMono-Regular, Consolas, monospace;
  font-size: 0.68rem;
  line-height: 1.55;
}

.button-light {
  grid-column: 1 / -1;
  width: fit-content;
  background: #f5f1e8;
  color: #171b1a;
}

.boundary-section::before {
  content: "界";
}

.boundary-grid {
  display: grid;
  grid-template-columns: 140px minmax(0, 700px);
  align-items: center;
  justify-content: center;
  gap: clamp(32px, 7vw, 80px);
}

.boundary-grid h2 {
  margin-bottom: 22px;
}

.boundary-grid p:last-child {
  margin: 0;
  color: var(--ink-soft);
}

.seal {
  display: grid;
  width: 124px;
  height: 124px;
  place-items: center;
  border: 4px double color-mix(in srgb, var(--vermilion) 80%, transparent);
  color: var(--vermilion);
  font-family: "ZCOOL KuaiLe", cursive;
  font-size: 4.4rem;
  transform: rotate(-3deg);
}

.final-cta {
  padding: clamp(78px, 10vw, 120px) 0;
}

.final-card {
  display: grid;
  max-width: 920px;
  justify-items: center;
  padding: clamp(46px, 7vw, 78px) clamp(24px, 7vw, 70px);
  border: 1px solid var(--line-strong);
  background: var(--card);
  text-align: center;
  box-shadow: var(--shadow);
}

.final-card p:not(.section-kicker) {
  max-width: 38rem;
  margin: 20px 0 28px;
  color: var(--ink-soft);
}

.site-footer {
  padding: 34px 0;
  border-top: 1px solid var(--line);
  color: var(--ink-faint);
  font-family: ui-sans-serif, system-ui, sans-serif;
  font-size: 0.75rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1fr auto auto;
  align-items: center;
  gap: 26px;
}

.footer-grid p {
  margin: 0;
}

@media (max-width: 900px) {
  .hero-grid,
  .flow-grid,
  .release-grid {
    grid-template-columns: 1fr;
  }

  .hero-copy {
    max-width: 680px;
  }

  .signal-illustration {
    width: min(520px, 100%);
    margin-inline: auto;
  }

  .card-grid {
    grid-template-columns: 1fr;
  }

  .feature-card {
    min-height: auto;
  }

  .feature-card h3 {
    margin-top: 28px;
  }

  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }

  .footer-brand {
    grid-column: 1 / -1;
  }
}

@media (max-width: 620px) {
  :root {
    --shell: min(100% - 28px, 1120px);
  }

  body {
    font-size: 15px;
  }

  .nav-shell {
    min-height: 66px;
  }

  .brand img {
    width: 38px;
    height: 38px;
  }

  .nav-download {
    font-size: 0.82rem;
  }

  .hero {
    padding-top: 54px;
  }

  h1 {
    font-size: clamp(2.7rem, 15vw, 4.2rem);
  }

  .hero-actions,
  .button {
    width: 100%;
  }

  .button {
    min-height: 54px;
  }

  .download-facts {
    gap: 4px 13px;
  }

  .download-facts li:not(:first-child)::before {
    margin-right: 11px;
  }

  .signal-illustration {
    min-height: 510px;
  }

  .phone-card {
    right: 0;
    width: min(270px, 78vw);
  }

  .source {
    min-width: 124px;
    padding: 14px;
  }

  .source-desktop {
    top: 112px;
  }

  .source-server {
    bottom: 63px;
    left: 0;
  }

  .signal-one {
    left: 104px;
    width: 120px;
  }

  .signal-two {
    left: 108px;
    width: 115px;
  }

  .vertical-inscription {
    display: none;
  }

  .feature-card {
    padding: 26px;
  }

  .flow-list li {
    grid-template-columns: 44px 1fr;
    gap: 12px;
  }

  .release-grid {
    gap: 42px;
  }

  .release-meta div {
    grid-template-columns: 1fr;
    gap: 3px;
  }

  .boundary-grid {
    grid-template-columns: 1fr;
  }

  .seal {
    width: 90px;
    height: 90px;
    font-size: 3.2rem;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  .footer-brand {
    grid-column: auto;
  }
}

@media (prefers-color-scheme: dark) {
  :root {
    --paper: #171b1a;
    --paper-deep: #202624;
    --card: #252b29;
    --ink: #f3efe5;
    --ink-soft: #c4cbc7;
    --ink-faint: #9da6a1;
    --line: rgba(238, 241, 232, 0.13);
    --line-strong: rgba(238, 241, 232, 0.24);
    --vermilion: #dc716b;
    --vermilion-dark: #ec8882;
    --gold: #c8aa65;
    --mist: rgba(255, 255, 255, 0.05);
    --shadow: 0 24px 70px rgba(0, 0, 0, 0.34);
  }

  body::before {
    opacity: 0.04;
    mix-blend-mode: screen;
  }

  .brand img,
  .phone-brand img {
    box-shadow: 0 8px 22px rgba(73, 172, 221, 0.18);
  }

  .phone-card,
  .feature-card,
  .source,
  .final-card {
    border-color: var(--line-strong);
  }

  .button-primary {
    color: #171b1a;
  }

  .release-section {
    background: #0f1211;
  }
}

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

  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
  }
}