/* RD 官网样式：无外部依赖，系统字体栈，暗色主题 */
:root {
  --bg: #0b0f16;
  --bg-soft: #111826;
  --bg-card: #141c2b;
  --border: #223049;
  --text: #e6edf7;
  --text-dim: #9aa8bd;
  --accent: #4c8dff;
  --accent-strong: #2f74f0;
  --ok: #3ecf8e;
  --radius: 14px;
  --maxw: 1120px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei", "PingFang SC",
    "Hiragino Sans GB", "Noto Sans CJK SC", "Source Han Sans SC", "WenQuanYi Zen Hei",
    Roboto, Helvetica, Arial, sans-serif;
  --mono: ui-monospace, SFMono-Regular, Menlo, Consolas, "Cascadia Mono", "Microsoft YaHei Mono",
    monospace;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: radial-gradient(1200px 600px at 50% -10%, #16223a 0%, var(--bg) 55%) no-repeat, var(--bg);
  color: var(--text);
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

.wrap { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

/* 顶部导航 */
.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  backdrop-filter: blur(10px);
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  border-bottom: 1px solid var(--border);
}
.header-inner { display: flex; align-items: center; justify-content: space-between; height: 62px; }
.brand { display: inline-flex; align-items: center; gap: 10px; color: var(--text); font-weight: 600; }
.brand:hover { text-decoration: none; }
.brand-mark { width: 24px; height: 24px; fill: none; stroke: var(--accent); stroke-width: 1.7; stroke-linecap: round; }
.nav { display: flex; gap: 22px; font-size: 14px; }
.nav a { color: var(--text-dim); }
.nav a:hover { color: var(--text); text-decoration: none; }

/* 首屏 */
.hero { padding: 88px 24px 56px; text-align: center; }
.eyebrow { color: var(--accent); font-size: 13px; letter-spacing: .08em; text-transform: uppercase; margin: 0 0 14px; }
.hero h1 { font-size: clamp(30px, 5vw, 48px); line-height: 1.2; margin: 0 0 18px; letter-spacing: -.01em; }
.lede { max-width: 720px; margin: 0 auto 30px; color: var(--text-dim); font-size: 17px; }
.hero-actions { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }
.hero-meta { color: var(--text-dim); font-size: 13px; margin: 22px 0 0; min-height: 1.4em; }

/* 按钮 */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  min-height: 44px; padding: 10px 22px; border-radius: 10px;
  font-size: 15px; font-weight: 600; border: 1px solid transparent;
  cursor: pointer; transition: transform .12s ease, background .12s ease, border-color .12s ease;
}
.btn:hover { text-decoration: none; transform: translateY(-1px); }
.btn:focus-visible, a:focus-visible, summary:focus-visible {
  outline: 2px solid var(--accent); outline-offset: 3px;
}
.btn-primary { background: var(--accent); color: #071022; }
.btn-primary:hover { background: var(--accent-strong); }
.btn-ghost { color: var(--text); border-color: var(--border); background: transparent; }
.btn-ghost:hover { border-color: var(--accent); }
.btn[aria-disabled="true"] { opacity: .55; pointer-events: none; }

/* 通用区块 */
.section { padding: 56px 24px; border-top: 1px solid var(--border); }
.section h2 { font-size: 24px; margin: 0 0 10px; }
.section-lede { color: var(--text-dim); margin: 0 0 26px; max-width: 780px; }
.note { color: var(--text-dim); font-size: 14px; }
.muted { color: var(--text-dim); }
.placeholder { border-bottom: 1px dashed var(--text-dim); }

.grid { display: grid; gap: 16px; }
.cards { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.card {
  background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 20px;
}
.card h3 { margin: 0 0 8px; font-size: 16px; }
.card p { margin: 0; color: var(--text-dim); font-size: 14.5px; }

/* 平台矩阵 */
.platforms { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.platform {
  background: var(--bg-soft); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 18px; display: grid; gap: 6px; align-content: start;
}
.platform .dot { width: 8px; height: 8px; border-radius: 50%; background: #3a465c; }
.platform.available .dot { background: var(--ok); }
.platform strong { font-size: 15px; }
.platform p { margin: 0; font-size: 13.5px; color: var(--text-dim); }
.tag {
  justify-self: start; font-size: 12px; padding: 1px 8px; border-radius: 999px;
  border: 1px solid var(--border); color: var(--text-dim);
}
.tag-ok { color: var(--ok); border-color: color-mix(in srgb, var(--ok) 45%, var(--border)); }

/* 下载区 */
.download-groups { display: grid; gap: 22px; }
.download-group h3 { font-size: 15px; color: var(--text-dim); margin: 0 0 10px; font-weight: 600; }
.download-list { display: grid; gap: 12px; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); }
.dl-card {
  background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 16px 18px; display: grid; gap: 10px; align-content: start;
}
.dl-head { display: flex; align-items: baseline; justify-content: space-between; gap: 10px; }
.dl-title { font-weight: 600; }
.dl-sub { color: var(--text-dim); font-size: 13px; }
.dl-actions { display: flex; gap: 10px; align-items: center; flex-wrap: wrap; }
.dl-actions .btn { min-height: 40px; padding: 8px 16px; font-size: 14px; }
.dl-card .planned {
  border: 1px dashed var(--border); border-radius: 10px; padding: 10px 14px;
  color: var(--text-dim); font-size: 14px;
}
.dl-meta { color: var(--text-dim); font-size: 12.5px; display: flex; gap: 12px; flex-wrap: wrap; }
details.sha { border-top: 1px solid var(--border); padding-top: 8px; }
details.sha summary { cursor: pointer; color: var(--text-dim); font-size: 13px; }
details.sha code {
  display: block; margin-top: 8px; padding: 8px 10px; background: #0a0f18;
  border: 1px solid var(--border); border-radius: 8px;
  font-family: var(--mono); font-size: 12.5px; word-break: break-all; color: var(--text);
}
.copy-btn {
  background: transparent; border: 1px solid var(--border); color: var(--text-dim);
  border-radius: 6px; font-size: 12px; padding: 2px 8px; cursor: pointer; margin-top: 8px;
}
.copy-btn:hover { border-color: var(--accent); color: var(--text); }
.download-status { margin: 18px 0 0; font-size: 14px; color: var(--text-dim); }
.download-status.error { color: #ffb4a8; }

.verify { margin-top: 18px; border: 1px solid var(--border); border-radius: var(--radius); padding: 12px 16px; background: var(--bg-soft); }
.verify summary { cursor: pointer; color: var(--text-dim); }
.verify pre, .steps pre {
  margin: 10px 0 0; padding: 12px 14px; background: #0a0f18; border: 1px solid var(--border);
  border-radius: 10px; overflow-x: auto; max-width: 100%;
}
pre code { font-family: var(--mono); font-size: 13px; color: #cfe0ff; }

/* 上手步骤 */
.steps { list-style: none; counter-reset: step; padding: 0; margin: 0; display: grid; gap: 16px; grid-template-columns: repeat(3, minmax(0, 1fr)); }
.steps > li {
  counter-increment: step; position: relative; min-width: 0;
  background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 20px 20px 18px;
}
.steps > li::before {
  content: counter(step); position: absolute; top: -12px; left: 18px;
  width: 26px; height: 26px; border-radius: 50%; background: var(--accent); color: #071022;
  display: grid; place-items: center; font-size: 13px; font-weight: 700;
}
.steps h3 { margin: 6px 0 8px; font-size: 16px; }
.steps p { margin: 0; color: var(--text-dim); font-size: 14.5px; }

/* 页脚 */
.site-footer { border-top: 1px solid var(--border); padding: 28px 0 40px; margin-top: 20px; }
.footer-inner { display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; font-size: 13px; }
.footer-inner p { margin: 0; }

/* 响应式 */
@media (max-width: 1024px) {
  .cards { grid-template-columns: repeat(2, 1fr); }
  .platforms { grid-template-columns: repeat(2, 1fr); }
  .steps { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
  .nav { display: none; }
  .hero { padding: 56px 24px 40px; }
  .section { padding: 40px 24px; }
  .cards, .platforms { grid-template-columns: 1fr; }
  .download-list { grid-template-columns: 1fr; }
  .dl-actions .btn { width: 100%; }
  .hero-actions { flex-direction: column; }
  .hero-actions .btn { width: 100%; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .btn { transition: none; }
  .btn:hover { transform: none; }
}