:root {
  --ink: #07111d;
  --ink-soft: #0d1724;
  --ink-card: #111b28;
  --gold: #ffcb38;
  --gold-deep: #bd8c12;
  --orange: #de4c24;
  --text: #f5f7fa;
  --muted: #a8b0bb;
  --paper: #ffffff;
  --paper-soft: #f3f3f3;
  --paper-text: #11151a;
  --danger: #d9363e;
  --content: 1140px;
  --content-gutter: 48px;
  --hero-content: 1200px;
  --body-font-size: 16px;
  --section-space: 110px;
  --section-title-size: clamp(29px, 3vw, 42px);
  --section-title-gap: 56px;
  --advantage-grid-gap: 18px;
  --project-grid-row-gap: 42px;
  --project-grid-column-gap: 38px;
  --other-project-content: 920px;
  --partner-content: 1168px;
  --radius: 10px;
  --header-height: 80px;
  color-scheme: dark;
  font-family: "Microsoft YaHei", "PingFang SC", Inter, Arial, sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-height) + 20px);
}

body {
  margin: 0;
  min-width: 320px;
  background: var(--ink);
  color: var(--text);
  font-size: var(--body-font-size);
  line-height: 1.65;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

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

button,
input,
select,
textarea {
  font: inherit;
}

button,
a {
  -webkit-tap-highlight-color: transparent;
}

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

h1,
h2,
h3,
h4,
p {
  margin-top: 0;
}

button {
  color: inherit;
}

:focus-visible {
  outline: 3px solid var(--gold);
  outline-offset: 4px;
}

.content-shell,
.header-shell {
  width: min(calc(100% - var(--content-gutter)), var(--content));
  margin-inline: auto;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: fixed;
  left: 18px;
  top: 12px;
  z-index: 1000;
  padding: 10px 14px;
  border-radius: 5px;
  background: var(--gold);
  color: #111;
  transform: translateY(-160%);
  transition: transform .2s ease;
}

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

.required {
  color: var(--danger);
  font-weight: 800;
}

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

  *,
  *::before,
  *::after {
    animation-duration: .01ms !important;
    animation-iteration-count: 1 !important;
    scroll-behavior: auto !important;
    transition-duration: .01ms !important;
  }
}