:root {
  color-scheme: light;
  --navy: #101b30;
  --text: #162644;
  --muted: #4b5b71;
  --paper: #f6f7f9;
  --line: #d9dfe8;
  --amber: #ffbc70;
  font-family: 'Instrument Sans', 'Microsoft YaHei', 'PingFang SC', 'Noto Sans CJK SC', sans-serif;
  color: var(--text);
  background: var(--paper);
  font-synthesis: none;
}

*, *::before, *::after { box-sizing: border-box; }
body { margin: 0; }
a { color: inherit; text-decoration: none; }
a:focus-visible { outline: 3px solid #2b73d5; outline-offset: 5px; }
.masthead a:focus-visible, .hero a:focus-visible { outline-color: var(--amber); }
h1, h2, h3, p { margin: 0; }
.frame { width: min(1200px, calc(100% - 88px)); margin-inline: auto; }

.masthead { background: var(--navy); color: #fff; border-bottom: 1px solid #a8bde72c; }
.site-header { min-height: 74px; display: flex; align-items: center; justify-content: space-between; gap: 24px; }
.brand, .brand > span { display: inline-flex; align-items: center; }
.brand { gap: 12px; font-size: 15px; font-weight: 700; white-space: nowrap; }
.brand img { border-radius: 8px; object-fit: contain; background: #fff; padding: 3px; }
.brand-divider { height: 14px; margin-inline: 9px; border-left: 1px solid #b4c2dd79; }
.site-header nav { display: flex; align-items: center; gap: clamp(16px, 4vw, 42px); font-size: 14px; color: #e1e7f3; }
.site-header nav a { padding-block: 12px; }
.site-header nav a:hover { color: var(--amber); }

.hero { position: relative; isolation: isolate; background: var(--navy); color: #fff; overflow: hidden; }
.hero-photo {
  position: absolute;
  z-index: -1;
  inset: 0 0 0 19%;
  background: linear-gradient(90deg, var(--navy), #101b30ec 13%, #101b3070 37%, #101b3000 69%),
    linear-gradient(0deg, #0d172ae8, #0e192a00 32%),
    url('./assets/fleet.png') center 60% / cover;
}
.hero-content { padding-block: 92px 88px; }
.hero h1 { font-size: clamp(52px, 5.7vw, 89px); line-height: 1.06; letter-spacing: -.045em; font-weight: 800; }
.hero-content > p:not(.release-note) { margin-top: 25px; max-width: 28em; color: #e1e9f8; font-size: 16px; line-height: 1.8; }
.primary-action { display: inline-flex; align-items: center; justify-content: center; gap: 12px; margin-top: 32px; min-height: 52px; padding-inline: 20px; border: 1px solid transparent; border-radius: 8px; background: var(--amber); color: #181e29; font-size: 15px; font-weight: 750; }
.primary-action:hover { background: #ffd09c; }
.release-note { margin-top: 13px; color: #c6d3e9; font-size: 13px; }
.download-icon { position: relative; width: 16px; height: 14px; border-bottom: 2px solid currentColor; }
.download-icon::before { position: absolute; content: ''; width: 2px; height: 9px; left: 7px; top: -1px; background: currentColor; }
.download-icon::after { position: absolute; content: ''; width: 7px; height: 7px; left: 4.5px; top: 2px; border: solid currentColor; border-width: 0 2px 2px 0; transform: rotate(45deg); }

.features { padding-block: 53px 58px; }
h2 { font-size: clamp(24px, 3vw, 32px); line-height: 1.25; letter-spacing: -.025em; }
.features-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 26px; margin-top: 28px; }
.features article { padding: 19px 8px 0 0; border-top: 2px solid #254470; }
.features h3 { font-size: 19px; }
.features p, .download-layout p { color: var(--muted); line-height: 1.75; font-size: 15px; margin-top: 9px; }

.download-section { background: #e9eff7; border-block: 1px solid var(--line); }
.download-layout { display: grid; grid-template-columns: 1fr 1.15fr; align-items: center; gap: 30px; padding-block: 36px; }
.download-options { display: grid; grid-template-columns: repeat(2, 1fr); gap: 12px; }
.download-options a { display: grid; gap: 6px; padding: 14px 18px; background: #fff; border: 1px solid #c7d3e3; border-radius: 8px; }
.download-options a:hover { border-color: #24579d; background: #f8fbff; }
.download-options strong { font-size: 15px; }
.download-options span { color: var(--muted); font-size: 13px; }
.site-footer { padding-block: 24px; font-size: 13px; color: var(--muted); }

@media (max-width: 760px) {
  .frame { width: calc(100% - 40px); }
  .site-header { min-height: 64px; gap: 12px; }
  .brand { gap: 7px; font-size: 13px; }
  .brand img { width: 30px; height: 30px; }
  .brand-divider { margin-inline: 5px; }
  .site-header nav { gap: 14px; font-size: 12px; }
  .hero-photo {
    inset: 0;
    background: linear-gradient(180deg, var(--navy) 0%, #101b30f7 23%, #101b30b0 49%, #101b3000 71%, #101b30d9 100%),
      url('./assets/fleet.png') center bottom / auto 72% no-repeat;
  }
  .hero-content { padding-block: 47px 174px; }
  .hero h1 { font-size: clamp(44px, 10vw, 62px); }
  .hero-content > p:not(.release-note) { margin-top: 18px; font-size: 15px; }
  .primary-action { margin-top: 24px; }
  .features { padding-block: 34px 38px; }
  .features-grid, .download-layout { grid-template-columns: 1fr; gap: 21px; }
  .features-grid { margin-top: 22px; }
  .features article { padding-top: 12px; }
  .download-layout { padding-block: 28px; }
}

@media (max-width: 370px) {
  .frame { width: calc(100% - 28px); }
  .site-header nav { gap: 9px; }
  .brand-divider { margin-inline: 4px; }
}