:root {
  --bg: #0b0e14;
  --bg-alt: #11151f;
  --fg: #e8eaed;
  --muted: #9aa3b2;
  --accent: #4cc9f0;
  --accent-2: #7b6cff;
  --card: #161b27;
  --border: #232a38;
  --radius: 14px;
  --grad: linear-gradient(135deg, var(--accent), var(--accent-2));
}

* { box-sizing: border-box; margin: 0; padding: 0; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Microsoft YaHei", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--fg);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  scroll-behavior: smooth;
}

a { color: inherit; text-decoration: none; }
kbd {
  display: inline-block; padding: 1px 7px; border-radius: 6px;
  background: #0c1018; border: 1px solid var(--border);
  font-size: 12px; font-family: inherit; color: var(--muted);
}

.container { max-width: 1080px; margin: 0 auto; padding: 0 24px; }

/* ===== 键盘焦点可见（无障碍） ===== */
:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; border-radius: 4px; }

/* ===== 导航 ===== */
.nav {
  position: sticky; top: 0; z-index: 20;
  background: rgba(11,14,20,.78);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.brand { font-weight: 700; font-size: 18px; display: flex; align-items: center; gap: 10px; }
.logo-mark {
  width: 32px; height: 32px; border-radius: 9px; background: var(--grad);
  display: inline-flex; align-items: center; justify-content: center;
  font-size: 17px; font-weight: 800; color: #07101a; flex: none;
}
.brand-name { display: flex; align-items: baseline; gap: 7px; }
.brand-name small { font-size: 12px; color: var(--muted); font-weight: 600; letter-spacing: .5px; }
.nav-links { display: flex; align-items: center; gap: 22px; }
.nav-links a { color: var(--muted); font-size: 15px; transition: color .2s; }
.nav-links a:hover { color: var(--fg); }

/* ===== 按钮 ===== */
.btn-primary, .btn-ghost {
  display: inline-block; padding: 12px 24px; border-radius: 10px;
  font-weight: 600; font-size: 15px; transition: transform .15s, opacity .2s, border-color .2s;
}
.btn-primary { background: var(--grad); color: #07101a; }
.btn-primary:hover { transform: translateY(-2px); }
.btn-ghost { border: 1px solid var(--border); color: var(--fg); }
.btn-ghost:hover { border-color: var(--accent); color: var(--accent); }

/* ===== 首屏 ===== */
.hero { position: relative; padding: 76px 0 30px; text-align: center; overflow: hidden; }
.hero-glow {
  position: absolute; top: -180px; left: 50%; transform: translateX(-50%);
  width: 760px; height: 520px; pointer-events: none;
  background: radial-gradient(closest-side, rgba(76,201,240,.22), rgba(123,108,255,.12) 60%, transparent 75%);
  filter: blur(20px);
}
.hero-inner { position: relative; display: flex; flex-direction: column; align-items: center; }
.badge {
  display: inline-block; padding: 5px 14px; border-radius: 999px;
  background: rgba(76,201,240,.12); color: var(--accent);
  font-size: 13px; margin-bottom: 22px; border: 1px solid rgba(76,201,240,.25);
}
.hero h1 { font-size: 54px; font-weight: 800; letter-spacing: -1px; }
.grad {
  background: var(--grad); -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent;
}
.tagline { color: var(--muted); font-size: 19px; max-width: 640px; margin: 16px 0 30px; }
.cta { display: flex; gap: 14px; flex-wrap: wrap; justify-content: center; }
.hero-stats {
  display: flex; flex-wrap: wrap; gap: 26px; justify-content: center;
  margin: 30px 0 6px; color: var(--muted); font-size: 15px;
}
.hero-stats b { color: var(--fg); font-size: 20px; margin-right: 4px; }

/* ===== 真实界面截图（软件实际运行画面） ===== */
.app-shot {
  margin: 46px auto 0; width: 100%; max-width: 980px;
  border-radius: 14px; box-shadow: 0 30px 70px rgba(0,0,0,.5);
}
.app-shot-bar {
  display: flex; align-items: center; gap: 12px; height: 42px; padding: 0 16px;
  background: #0e131c; border: 1px solid var(--border); border-bottom: none;
  border-radius: 14px 14px 0 0;
}
.dots { display: flex; gap: 7px; }
.dots i { width: 11px; height: 11px; border-radius: 50%; background: #2b3342; display: block; }
.dots i:nth-child(1) { background: #ff5f57; }
.dots i:nth-child(2) { background: #febc2e; }
.dots i:nth-child(3) { background: #28c840; }
.app-shot-title { font-size: 13px; color: var(--muted); }
.app-shot img {
  display: block; width: 100%; height: auto;
  border: 1px solid var(--border); border-radius: 0 0 14px 14px; background: #0b0e14;
}
.app-shot figcaption { margin-top: 14px; font-size: 13px; color: var(--muted); text-align: center; }

/* ===== 区块 ===== */
.section { padding: 78px 0; }
.section-alt { background: var(--bg-alt); }
.section-title { text-align: center; font-size: 32px; font-weight: 700; margin-bottom: 10px; }
.center-sub { text-align: center; color: var(--muted); margin-bottom: 38px; }
.center-sub.small { font-size: 14px; margin-top: 24px; }

/* ===== 介绍：文字 + 规格表 ===== */
.about-grid { display: grid; grid-template-columns: 1.1fr .9fr; gap: 34px; align-items: start; }
.about-text > p { color: var(--muted); font-size: 15px; margin-bottom: 14px; }
.about-points { list-style: none; margin-top: 20px; display: flex; flex-direction: column; gap: 11px; }
.about-points li { position: relative; padding-left: 20px; color: var(--muted); font-size: 14.5px; }
.about-points li::before {
  content: ""; position: absolute; left: 0; top: 9px;
  width: 7px; height: 7px; border-radius: 50%; background: var(--accent);
}
.about-points b { color: var(--fg); font-weight: 600; }
.spec { background: var(--card); border: 1px solid var(--border); border-radius: var(--radius); overflow: hidden; }
.spec-row {
  display: flex; justify-content: space-between; gap: 18px;
  padding: 13px 18px; border-bottom: 1px solid var(--border); font-size: 14px;
}
.spec-row:last-child { border-bottom: none; }
.spec-row span { color: var(--muted); flex: none; }
.spec-row b { color: var(--fg); font-weight: 600; text-align: right; }

/* ===== 功能分组 ===== */
.feature-groups { display: flex; flex-direction: column; gap: 16px; max-width: 900px; margin: 0 auto; }
.fgroup {
  background: var(--card); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 22px 24px;
}
.fgroup > h3 { font-size: 18px; margin-bottom: 14px; display: flex; align-items: center; gap: 10px; }
.fgroup-tag {
  font-size: 12px; font-weight: 600; color: var(--accent);
  background: rgba(76,201,240,.12); padding: 2px 9px; border-radius: 999px;
}
.fpage { padding: 12px 0; border-top: 1px solid var(--border); }
.fpage:first-of-type { border-top: none; padding-top: 0; }
.fpage-name { display: inline-block; font-size: 15px; font-weight: 600; color: var(--fg); margin-bottom: 6px; }
.fpage p { color: var(--muted); font-size: 14px; }

/* ===== 使用步骤 ===== */
.steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; max-width: 880px; margin: 0 auto; }
.step {
  background: var(--card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 26px 22px; text-align: center;
}
.step-num {
  width: 40px; height: 40px; border-radius: 50%; background: var(--grad); color: #07101a;
  font-weight: 800; font-size: 18px; display: inline-flex; align-items: center; justify-content: center; margin-bottom: 14px;
}
.step h4 { font-size: 18px; margin-bottom: 8px; }
.step p { color: var(--muted); font-size: 14px; }

/* ===== 下载 ===== */
.download-grid { display: flex; justify-content: center; flex-wrap: wrap; gap: 18px; max-width: 720px; margin: 0 auto; }
.dl-card {
  background: var(--card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 26px 48px; text-align: center; transition: transform .2s, border-color .2s;
}
.dl-card:hover { transform: translateY(-4px); border-color: var(--accent); }
.dl-os { display: block; font-size: 20px; font-weight: 700; }
.dl-ext { color: var(--muted); font-size: 13px; }

/* ===== FAQ ===== */
.faq-wrap { max-width: 760px; }
.faq {
  background: var(--card); border: 1px solid var(--border); border-radius: 12px;
  padding: 4px 18px; margin-bottom: 12px;
}
.faq summary {
  cursor: pointer; padding: 14px 0; font-weight: 600; font-size: 16px;
  list-style: none; position: relative; padding-right: 24px;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; position: absolute; right: 0; top: 14px; color: var(--accent); font-size: 20px; }
.faq[open] summary::after { content: "−"; }
.faq p { color: var(--muted); font-size: 14.5px; padding: 0 0 16px; }

/* ===== 页脚 ===== */
.footer { border-top: 1px solid var(--border); padding: 40px 0; }
.footer-inner { display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 16px; }
.footer-note { color: var(--muted); font-size: 13px; margin-top: 8px; }
.footer-links { display: flex; gap: 20px; }
.footer-links a { color: var(--muted); font-size: 14px; }
.footer-links a:hover { color: var(--fg); }

/* ===== 响应式 ===== */
@media (max-width: 900px) {
  .about-grid { grid-template-columns: 1fr; gap: 24px; }
  .steps { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 620px) {
  .steps { grid-template-columns: 1fr; }
  .nav-links { gap: 13px; font-size: 14px; }
  .hero h1 { font-size: 36px; }
  .tagline { font-size: 16px; }
  .app-shot { margin-top: 32px; }
  .app-shot figcaption { font-size: 12px; }
  .spec-row { flex-direction: column; gap: 4px; }
  .spec-row b { text-align: left; }
  .fgroup { padding: 18px 16px; }
}

/* ===== 滚动入场动画 ===== */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity .7s ease, transform .7s ease; }
.reveal.visible { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1 !important; transform: none !important; transition: none; }
  .hero .badge, .hero h1, .hero .tagline, .hero .cta,
  .hero .hero-stats, .hero .app-shot { animation: none !important; }
}
/* 首屏分级渐入 */
.hero .badge     { animation: fadeUp .7s .05s both; }
.hero h1         { animation: fadeUp .7s .15s both; }
.hero .tagline   { animation: fadeUp .7s .25s both; }
.hero .cta       { animation: fadeUp .7s .35s both; }
.hero .hero-stats{ animation: fadeUp .7s .45s both; }
.hero .app-shot  { animation: fadeUp .9s .55s both; }
@keyframes fadeUp { from { opacity: 0; transform: translateY(24px); } to { opacity: 1; transform: none; } }

/* ===== 下载主按钮 ===== */
.dl-card.primary { background: var(--grad); border: none; }
.dl-card.primary .dl-os, .dl-card.primary .dl-ext { color: #07101a; }
.dl-card.primary:hover { transform: translateY(-4px); box-shadow: 0 14px 30px rgba(76,201,240,.25); }

/* ===== 更新日志 ===== */
.changelog-list { max-width: 820px; margin: 0 auto; display: flex; flex-direction: column; gap: 18px; }
.changelog-item { background: var(--card); border: 1px solid var(--border); border-radius: var(--radius); padding: 22px 24px; text-align: left; transition: border-color .2s; }
.changelog-item:hover { border-color: var(--accent); }
.cl-head { display: flex; align-items: center; gap: 12px; margin-bottom: 12px; flex-wrap: wrap; }
.cl-ver { font-size: 18px; font-weight: 800; color: var(--fg); }
.cl-ver a { color: inherit; }
.cl-date { font-size: 13px; color: var(--muted); }
.cl-tag { font-size: 12px; color: var(--accent); background: rgba(76,201,240,.12); padding: 2px 9px; border-radius: 999px; }
.cl-title { font-size: 15px; color: var(--fg); margin-bottom: 10px; }
.cl-items { list-style: none; display: flex; flex-direction: column; gap: 7px; }
.cl-items li { font-size: 14px; color: var(--muted); padding-left: 18px; position: relative; }
.cl-items li::before { content: "▹"; position: absolute; left: 0; color: var(--accent); }

/* ===== 导航当前区块高亮 ===== */
.nav-links a { position: relative; }
.nav-links a.active { color: var(--fg); }
.nav-links a.active::after {
  content: ""; position: absolute; left: 0; right: 0; bottom: -6px;
  height: 2px; border-radius: 2px; background: var(--grad);
}

/* ===== 汉堡菜单按钮 ===== */
.nav-toggle {
  display: none; width: 42px; height: 42px; border-radius: 10px;
  background: transparent; border: 1px solid var(--border); cursor: pointer;
  flex-direction: column; align-items: center; justify-content: center; gap: 5px;
}
.nav-toggle span {
  display: block; width: 20px; height: 2px; border-radius: 2px;
  background: var(--fg); transition: transform .25s, opacity .2s;
}
.nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ===== 返回顶部 ===== */
.to-top {
  position: fixed; right: 22px; bottom: 22px; z-index: 30;
  width: 46px; height: 46px; border-radius: 50%; border: 1px solid var(--border);
  background: var(--card); color: var(--fg); font-size: 20px; cursor: pointer;
  opacity: 0; visibility: hidden; transform: translateY(10px);
  transition: opacity .25s, transform .25s, border-color .2s, visibility .25s;
  box-shadow: 0 10px 30px rgba(0,0,0,.4);
}
.to-top.show { opacity: 1; visibility: visible; transform: none; }
.to-top:hover { border-color: var(--accent); color: var(--accent); }

/* ===== 移动端导航折叠 ===== */
@media (max-width: 820px) {
  .nav-toggle { display: inline-flex; }
  .nav-links {
    position: absolute; top: 64px; left: 0; right: 0;
    flex-direction: column; align-items: stretch; gap: 0;
    background: rgba(11,14,20,.98); -webkit-backdrop-filter: blur(12px); backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
    padding: 8px 24px 16px;
    max-height: 0; overflow: hidden; opacity: 0; pointer-events: none;
    transition: max-height .28s ease, opacity .2s ease;
  }
  .nav-links.open { max-height: 460px; opacity: 1; pointer-events: auto; }
  .nav-links a { padding: 12px 0; font-size: 15px; border-bottom: 1px solid var(--border); color: var(--fg); }
  .nav-links a:last-child { border-bottom: none; margin-top: 10px; }
  .nav-links a.active::after { display: none; }
}