:root {
  --bg: #101722;
  --panel: #182232;
  --panel-soft: #202b3b;
  --line: rgba(255, 255, 255, 0.12);
  --text: #f4f7fb;
  --muted: #9caabd;
  --soft: #d7dee8;
  --orange: #f59e0b;
  --orange-strong: #f97316;
  --green: #2fbf71;
  --cyan: #35b6cc;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "Segoe UI", "Microsoft YaHei", Arial, sans-serif;
  color: var(--text);
  background: var(--bg);
}

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 16px clamp(20px, 5vw, 72px);
  background: rgba(16, 23, 34, 0.88);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(14px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 18px;
}

.brand img {
  width: 34px;
  height: 34px;
}

.top-nav {
  display: flex;
  align-items: center;
  gap: 22px;
  color: var(--muted);
  font-size: 14px;
}

.top-nav a:hover {
  color: var(--orange);
}

.hero {
  min-height: 92vh;
  display: grid;
  grid-template-columns: minmax(0, 0.85fr) minmax(460px, 1.15fr);
  gap: clamp(32px, 5vw, 72px);
  align-items: center;
  padding: clamp(48px, 8vw, 96px) clamp(20px, 5vw, 72px) 64px;
  background:
    linear-gradient(120deg, rgba(245, 158, 11, 0.16), rgba(53, 182, 204, 0.08) 42%, transparent 64%),
    linear-gradient(180deg, #111927 0%, #101722 100%);
}

.hero-copy {
  max-width: 660px;
}

.eyebrow {
  margin: 0 0 12px;
  color: var(--orange);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0;
  text-transform: uppercase;
}

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

h1 {
  margin-bottom: 18px;
  font-size: clamp(48px, 7vw, 86px);
  line-height: 1.02;
}

h2 {
  margin-bottom: 14px;
  font-size: clamp(28px, 4vw, 44px);
  line-height: 1.14;
}

h3 {
  margin-bottom: 10px;
  font-size: 20px;
}

.hero-text {
  max-width: 580px;
  color: var(--soft);
  font-size: 19px;
  line-height: 1.75;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 30px;
}

.backup-download {
  margin-top: 14px;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.7;
}

.backup-download a {
  color: var(--orange);
}

.backup-download span {
  margin-left: 8px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 0 20px;
  border-radius: 8px;
  font-weight: 700;
  border: 1px solid var(--line);
}

.button.primary {
  color: #111927;
  background: var(--orange);
  border-color: var(--orange);
}

.button.secondary {
  color: var(--text);
  background: rgba(255, 255, 255, 0.05);
}

.product-preview {
  width: 100%;
  min-width: 0;
}

.app-shell {
  display: grid;
  grid-template-columns: 180px minmax(0, 1fr);
  min-height: 510px;
  border: 1px solid var(--line);
  border-radius: 8px;
  overflow: hidden;
  background: #121b29;
  box-shadow: 0 28px 80px rgba(0, 0, 0, 0.32);
}

.preview-sidebar {
  padding: 18px 14px;
  background: #0d1522;
  border-right: 1px solid var(--line);
}

.preview-logo {
  display: flex;
  align-items: center;
  gap: 9px;
  padding-bottom: 16px;
  margin-bottom: 16px;
  border-bottom: 1px solid var(--line);
  font-size: 15px;
}

.preview-logo img {
  width: 30px;
  height: 30px;
}

.preview-sidebar span {
  display: block;
  padding: 11px 12px;
  margin-bottom: 6px;
  border-radius: 7px;
  color: var(--muted);
  font-size: 14px;
}

.preview-sidebar .active {
  color: var(--orange);
  background: rgba(245, 158, 11, 0.13);
  border-right: 3px solid var(--orange);
}

.preview-main {
  padding: 24px;
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.04), transparent 48%),
    #152031;
}

.preview-toolbar {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  align-items: center;
  margin-bottom: 20px;
}

.preview-toolbar small,
.symbol-grid span {
  color: var(--muted);
}

.preview-toolbar strong {
  display: block;
  font-size: 32px;
}

.preview-toolbar button {
  border: 0;
  border-radius: 8px;
  padding: 12px 18px;
  color: #101722;
  font-weight: 700;
  background: linear-gradient(135deg, var(--orange), var(--orange-strong));
}

.symbol-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
}

.symbol-grid article,
.feature-card,
.release-box > div {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.045);
}

.symbol-grid article {
  min-height: 128px;
  padding: 16px;
}

.symbol-grid b,
.symbol-grid span,
.symbol-grid i {
  display: block;
}

.symbol-grid span {
  margin: 14px 0;
  font-size: 13px;
  line-height: 1.5;
}

.symbol-grid i {
  color: var(--green);
  font-style: normal;
  font-weight: 700;
}

.strategy-panel {
  margin-top: 18px;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.035);
}

.panel-line {
  height: 12px;
  margin: 12px 0;
  border-radius: 8px;
  background: rgba(156, 170, 189, 0.28);
}

.panel-line.strong {
  width: 82%;
  background: rgba(245, 158, 11, 0.52);
}

.panel-line.short {
  width: 58%;
  background: rgba(53, 182, 204, 0.45);
}

.section {
  padding: 76px clamp(20px, 5vw, 72px);
}

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

.section-text {
  color: var(--soft);
  line-height: 1.8;
  font-size: 17px;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
}

.feature-card {
  padding: 22px;
}

.feature-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 38px;
  height: 38px;
  margin-bottom: 22px;
  border-radius: 8px;
  color: #101722;
  font-weight: 800;
  background: var(--orange);
}

.feature-card p,
.release-box p,
.security-band p {
  color: var(--muted);
  line-height: 1.75;
}

.split {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(360px, 1.1fr);
  gap: clamp(30px, 5vw, 70px);
  align-items: start;
  background: #121b28;
}

.steps {
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--line);
}

.steps li {
  display: grid;
  grid-template-columns: 130px minmax(0, 1fr);
  gap: 20px;
  padding: 20px 0;
  border-bottom: 1px solid var(--line);
}

.steps span {
  color: var(--muted);
}

.security-band {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(320px, 0.75fr);
  gap: clamp(28px, 4vw, 56px);
  align-items: center;
  background: linear-gradient(90deg, #172235, #111927);
}

.security-list {
  display: grid;
  gap: 10px;
}

.security-list span {
  padding: 13px 16px;
  border: 1px solid rgba(53, 182, 204, 0.28);
  border-radius: 8px;
  background: rgba(53, 182, 204, 0.08);
}

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

.release-box > div {
  padding: 22px;
}

.download-box {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 22px;
  margin-top: 18px;
  padding: 24px;
  border: 1px solid rgba(245, 158, 11, 0.34);
  border-radius: 8px;
  background: rgba(245, 158, 11, 0.08);
}

.download-box h3 {
  margin-bottom: 8px;
}

.download-box p {
  margin-bottom: 0;
  color: var(--muted);
}

.download-actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 12px;
}

.site-footer {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  padding: 28px clamp(20px, 5vw, 72px);
  color: var(--muted);
  border-top: 1px solid var(--line);
  background: #0d1522;
}

@media (max-width: 980px) {
  .hero,
  .split,
  .security-band {
    grid-template-columns: 1fr;
  }

  .product-preview {
    margin-top: 4px;
  }

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

@media (max-width: 720px) {
  .site-header {
    align-items: flex-start;
    flex-direction: column;
  }

  .top-nav {
    width: 100%;
    overflow-x: auto;
    padding-bottom: 2px;
  }

  h1 {
    font-size: 44px;
  }

  .app-shell {
    grid-template-columns: 1fr;
  }

  .preview-sidebar {
    display: none;
  }

  .symbol-grid,
  .feature-grid,
  .release-box {
    grid-template-columns: 1fr;
  }

  .steps li {
    grid-template-columns: 1fr;
    gap: 6px;
  }

  .site-footer {
    flex-direction: column;
  }

  .download-box {
    align-items: flex-start;
    flex-direction: column;
  }

  .download-actions {
    width: 100%;
    justify-content: flex-start;
  }
}