:root {
  color-scheme: light dark;
  --bg: #ffffff;
  --ink: #172a2d;
  --muted: #637174;
  --soft: #f5f8f7;
  --panel: rgba(255, 255, 255, 0.88);
  --line: rgba(23, 42, 45, 0.1);
  --primary: #2b6f77;
  --primary-deep: #17464d;
  --coral: #d95d39;
  --green: #4a8c68;
  --gold: #d6a429;
  --shadow: 0 20px 60px rgba(23, 42, 45, 0.1);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--bg);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Display", "SF Pro Text", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  letter-spacing: 0;
}

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

a {
  color: inherit;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(255, 255, 255, 0.82);
  backdrop-filter: blur(18px);
  border-bottom: 1px solid var(--line);
}

.nav {
  width: min(1120px, calc(100% - 32px));
  min-height: 68px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  font-weight: 800;
}

.brand img {
  width: 38px;
  height: 38px;
  border-radius: 10px;
  box-shadow: 0 8px 18px rgba(23, 42, 45, 0.12);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 18px;
  color: var(--muted);
  font-size: 15px;
  font-weight: 650;
}

.nav-links a {
  text-decoration: none;
}

.hero {
  position: relative;
  overflow: hidden;
  min-height: min(760px, calc(100svh - 68px));
  display: grid;
  align-items: center;
  border-bottom: 1px solid var(--line);
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: url("./assets/app-icon.png");
  background-size: min(86vw, 780px);
  background-repeat: no-repeat;
  background-position: right -90px center;
  opacity: 0.08;
}

.hero-inner {
  position: relative;
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto;
  padding: 74px 0 64px;
}

.hero-copy {
  max-width: 720px;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin: 0 0 18px;
  padding: 8px 13px;
  color: var(--primary-deep);
  background: rgba(43, 111, 119, 0.1);
  border: 1px solid rgba(43, 111, 119, 0.15);
  border-radius: 999px;
  font-size: 14px;
  font-weight: 750;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1 {
  margin-bottom: 22px;
  font-size: clamp(48px, 7vw, 86px);
  line-height: 1.02;
  font-weight: 950;
  letter-spacing: 0;
}

.lead {
  max-width: 660px;
  margin-bottom: 30px;
  color: var(--muted);
  font-size: clamp(18px, 2.4vw, 24px);
  line-height: 1.58;
  font-weight: 520;
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 20px;
  border-radius: 14px;
  text-decoration: none;
  font-weight: 800;
  border: 1px solid transparent;
}

.button.primary {
  color: #ffffff;
  background: var(--primary);
  box-shadow: 0 14px 28px rgba(43, 111, 119, 0.22);
}

.button.secondary {
  color: var(--primary-deep);
  background: var(--soft);
  border-color: var(--line);
}

.hero-preview {
  width: min(760px, 100%);
  margin-top: 50px;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
}

.preview-item {
  min-height: 160px;
  padding: 14px;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 24px;
  box-shadow: var(--shadow);
}

.preview-item img {
  width: 92px;
  height: 128px;
  margin: 0 auto 10px;
  object-fit: contain;
  border-radius: 18px;
  background: #ffffff;
}

.preview-item strong,
.preview-item span {
  display: block;
  text-align: center;
}

.preview-item strong {
  font-size: 18px;
}

.preview-item span {
  margin-top: 4px;
  color: var(--muted);
  font-size: 13px;
  font-weight: 650;
}

.section {
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto;
  padding: 76px 0;
}

.section.compact {
  padding-top: 42px;
}

.section-title {
  max-width: 760px;
  margin-bottom: 28px;
}

.section-title h2 {
  margin-bottom: 12px;
  font-size: clamp(32px, 4vw, 52px);
  line-height: 1.12;
  font-weight: 920;
}

.section-title p {
  color: var(--muted);
  font-size: 18px;
  line-height: 1.7;
}

.grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
}

.card,
.support-panel,
.policy-panel {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 24px;
  box-shadow: var(--shadow);
}

.card {
  padding: 24px;
}

.card .num {
  width: 38px;
  height: 38px;
  display: grid;
  place-items: center;
  margin-bottom: 18px;
  color: #ffffff;
  background: var(--primary);
  border-radius: 12px;
  font-weight: 900;
}

.card h3 {
  margin-bottom: 10px;
  font-size: 22px;
}

.card p {
  color: var(--muted);
  line-height: 1.7;
}

.support-panel {
  padding: 30px;
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 24px;
}

.support-list {
  display: grid;
  gap: 12px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.support-list li {
  padding: 14px 16px;
  color: var(--muted);
  background: var(--soft);
  border: 1px solid var(--line);
  border-radius: 16px;
  line-height: 1.6;
}

.contact-card {
  padding: 24px;
  background: var(--primary);
  color: #ffffff;
  border-radius: 22px;
}

.contact-card p {
  color: rgba(255, 255, 255, 0.78);
  line-height: 1.7;
}

.contact-card a {
  display: inline-flex;
  min-height: 46px;
  align-items: center;
  justify-content: center;
  margin-top: 10px;
  padding: 0 16px;
  color: var(--primary-deep);
  background: #ffffff;
  border-radius: 13px;
  text-decoration: none;
  font-weight: 850;
}

.page-hero {
  width: min(900px, calc(100% - 32px));
  margin: 0 auto;
  padding: 76px 0 30px;
}

.page-hero h1 {
  font-size: clamp(42px, 6vw, 72px);
}

.page-hero p {
  color: var(--muted);
  font-size: 18px;
  line-height: 1.75;
}

.policy-panel {
  width: min(900px, calc(100% - 32px));
  margin: 0 auto 80px;
  padding: 34px;
}

.policy-panel h2 {
  margin: 34px 0 12px;
  font-size: 26px;
}

.policy-panel h2:first-child {
  margin-top: 0;
}

.policy-panel p,
.policy-panel li {
  color: var(--muted);
  line-height: 1.85;
}

.policy-panel ul {
  padding-left: 22px;
}

.site-footer {
  border-top: 1px solid var(--line);
  color: var(--muted);
}

.footer-inner {
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto;
  padding: 28px 0;
  display: flex;
  flex-wrap: wrap;
  gap: 12px 20px;
  align-items: center;
  justify-content: space-between;
  font-size: 14px;
}

.footer-links {
  display: flex;
  gap: 16px;
}

.footer-links a {
  text-decoration: none;
}

@media (max-width: 820px) {
  .nav {
    min-height: 62px;
  }

  .nav-links {
    gap: 12px;
    font-size: 14px;
  }

  .hero {
    min-height: auto;
  }

  .hero-inner {
    padding-top: 48px;
  }

  .hero::before {
    background-size: 520px;
    background-position: right -180px top 18px;
  }

  .hero-preview,
  .grid,
  .support-panel {
    grid-template-columns: 1fr;
  }

  .preview-item {
    display: grid;
    grid-template-columns: 82px 1fr;
    align-items: center;
    gap: 14px;
    min-height: 112px;
  }

  .preview-item img {
    width: 76px;
    height: 96px;
    margin: 0;
  }

  .preview-item strong,
  .preview-item span {
    text-align: left;
  }

  .section {
    padding: 54px 0;
  }
}

@media (max-width: 520px) {
  .brand span {
    max-width: 8em;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
  }

  .nav-links a:first-child {
    display: none;
  }

  .actions {
    display: grid;
  }

  .button {
    width: 100%;
  }

  .policy-panel {
    padding: 24px;
  }
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #101415;
    --ink: #eef4f3;
    --muted: #aebcbe;
    --soft: #172123;
    --panel: rgba(23, 30, 31, 0.9);
    --line: rgba(238, 244, 243, 0.1);
    --shadow: 0 20px 60px rgba(0, 0, 0, 0.24);
  }

  .site-header {
    background: rgba(16, 20, 21, 0.82);
  }

  .preview-item img,
  .button.secondary {
    background: #ffffff;
  }

  .button.secondary {
    color: #17464d;
  }
}